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  • 1.
    Abrahamsson, Sten
    et al.
    Gotland University, School of the Humanities and Social Science.
    Isaksson, Raine
    Gotland University, School of the Humanities and Social Science.
    Implementing Lean: Discussing Standardization Versus Customization with Focus on National Cultural Dimensions2012In: Management and Production Engineering Review, ISSN 2082-1344, Vol. 3, no 4, p. 4-13Article in journal (Refereed)
    Abstract [en]

    Lean or Toyota Production System (TPS) has more or less successfully been implemented in the Western world’s businesses and organizations for the past 20 years. Several authors have discussed what it is that creates a successful implementation, and several studies have been presented where strategies for implementations have been studied. Culture’s impact and possible mitigation for Western companies have been studied and described by for example Womak & Jones. Proponents of the concept of Lean argue that culture is not a constraint for implementation of Lean. Lean Management is called a philosophy but it is often used as a change strategy in the sense that it is implemented with the view of improving performance. A change strategy could be seen as a product that might have to be customized with the view of improving the effectiveness of the implementation. On the other hand abandoning a standardized approach comes with the risk of severely altering the change strategy, possibly to its detriment. Implementing Lean will have an effect on the company culture. Does it make any sense customizing the implementation to culture if the issue is changing the culture? The purpose of this paper is to highlight and discuss the balance between a customized implementation and a standardized implementation. Which are the main arguments for standardization and customization and how could these be reconciled? A literature study of Lean implementation has been carried out and compared with Lean principles and theories from change management with focus on change drivers and change barriers. Main drivers of Hofstede’s national cultural dimensions are compared with Lean principles to identify possible drivers and barriers in different cultures. The theory synthesis on drivers and barriers is subjected to a first test in a case study on Lean implementation according to a standardized approach. The implementation is made in a small Swedish factory belonging to a worldwide industrial company. Results from the literature review and the case study indicate that both customization and standardization are needed.

  • 2.
    Abujheisha, Belal
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences.
    Laserinkopplingselement För XFEL Laser Heater: Från Idé Till Färdig Produkt I Designstadie2011Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Uppsala University is involved in a large international collaborationto build the Laser heater system for the European Xray Free-electronlaser in Hamburg, Germany. In this thesis I describe a laser incouplingdevice into the vacuum chamber of this laser heater all the way fromthe specifications to a completed design.

    The laser heater is a very important part of the XFEL and thepart described here is a part of the vacuum system needed to couplean external laser into the electron vacuum system and align it withthe electron bunches in order to heat them. The task was started by studying the literature about the basic theory andthe design of vacuum systems. After this study and collection of ideaswith colleagues I started to prepare different concepts to solve thetask. The ideas can be put into two categories, in one case the couplingmirror is located inside the vacuum chamber and in the second caseoutside. The concepts were evaluated with colleagues from the physicsdepartment and one solution from each category was evaluated further. The work continued to develop and refine these concpets. During the workseveral obstacles appeared, the biggest one was that with the 'inside'concept some of the design constraints had to be disregarded, butduring further work the design was adapted and the problems weremostly solved.

    The concept with the mirror outside the vacuumchamber was succesfuland the design was completed. In this thesis SolidWorks was used for the design work of thedifferent concepts and all parts that are part of the icouplingelement for the XFEL laser heater. All drawings are generated inSolidWorks as well and are attached to this report.

  • 3.
    Adle, Tobias
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics.
    Framtagning av metod för analys av livslängdsdata2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Husqvarna AB has as of today an extensive research and development department.This department serves to control the active product as well as the upcoming ones.The way that is done is through two different sets of tests. The first one being a longterm endurance test with aimed to unveil the durability of a product. Second and finalsort of test is a more one dimensional one. The aim is to determine different specificunits of interest like for example Newton (N).

    Today the R&D department has a great knowledge within normal distributed data andsomewhat less when it comes to the opposite, so called none normal distributed data.When endurance is of interest the likelihood of that to be of the latter sort is morecommon than not. For now no complete method has been appointed to make iteasier to process a situation of this kind. Studying ever unique case individually, bylooking at the data, has been the way to go. This causes an inconsistency in theanalysis and makes it purely based on which individual that has done it. Lastly it mayalso, unintentionally, ignore the large picture of how a product has progressed.

    To solve these problems this thesis work was put together to propose and conduct amethod. To form this method was an ongoing process throughout the whole thesisperiod. Ideas and thoughts were put forward to be reviewed and discussed. After aseries of tweaks to steer it towards the overall goal the method was finalized. Themethod that was put forward was firmly tested. Also a wide laboration in what themethod actually meant was done.

    The result was a method to be applied on none normal distributed data. This methodhas three parts. The first being the report where everything is embraced. The secondpart is a short manual for an operator to use. Last part is an example where themethod is put to use.

  • 4.
    Adolfsson, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Simplified finite element bearing modeling: with NX Nastran2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report was produced at the request of ABB Robotics and the work was conducted at their facilities in Västerås, Sweden.

    In the development of industrial robots the structures are slimmed to increase the accuracy and speed. When conducting finite element analysis on the robots the accuracy of the component modelling and definitions of the boundary conditions becomes more important. One such component is the ball bearing which consist of several parts and has a nonlinear behavior where the balls are in contact with the rings.

    The task given was to develop new methods to model roller bearings in Siemens finite element modelling software NX Nastran. Then conduct a strain measurement, to compare the methods to real experimental values. The goal with the report is to find one or more methods to model roller bearings, with accurate results, that can beused in their development work.

    The report was conducted by first doing a study on bearings and finite element modeling, and learning to use the software NX Nastran. Then the development of the methods were done by generating ideas for bearing models and testing them on simple structures. Nine methods was produced and a tenth, the method used to model bearings today, was used as a reference. The methods was used to build bearing models in a finite element model of a six axis robot wrist.

    Simulations were done on the models with different load cases and the results were compared to a strain measurement of the wrists real counterpart. Only six of the models were analyzed in the result, since four of the models returned results that were deemed unusable.

    When compiling the result data no model was found to accurately recreate the stresses in every load case. Three methods, that allow deformation, performed similarly. One of them is suggested to be used as modelling method in the future. Worst of the methods, according to the results compiled, was found to be the method used today. It fails to describe local stresses around the bearing. For continued work it is suggested that linear contact elements is studied further. Four out of five models constructed with linear contact elements failed to return satisfactory results.

  • 5. Adrovic, Dzemil
    Utveckling av metoder att mäta centrering av skruvhål i skär2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There have been, in some rare cases, difficulties with clamping of inserts with U-holes

    in their tool holder. According to the complaints, the inserts could not be properly

    clamped or could fracture when clamped. A study has shown that variations in

    clamping behaviour are mainly depending by the position of the screw hole in the tool

    holder and the centering of the screw hole in the insert.

    The focus of this project has been the centering of screw hole in insert. It has been

    shown that the screw holes are not always enough centered in the insert. The

    problem may occur after a certain step in the production, i.e. peripheral grinding.

    Today, the centering can be measured by a certain measurement jig. The

    measurement jig has a very good Gauge R and R value but is not easy to use,

    especially if it is to be reinstated into the production. The aim of this thesis has been

    to use SmartScope for developing a new method for measuring the centering of

    screw hole in insert. The goal with the new method was to be able to measure faster

    and to be easier to use than the existing one.

    The project was started with exercises and exploration of some of the functions of

    SmartScope and its software Measuremind 3D. Parallel with this, a study was made of

    the existing documentation for a better understanding of the problem.

    A method which measures how well the screw holes are centered in their inserts has

    been developed. The method consists of a number of measuring tools which are

    joined into a measurement sequence. Measurements of single inserts are fully

    automated. Provided that a system which picks and puts the inserts in specific

    locations can be implemented, a series of inserts can be measured fully automated.

    This method is faster and especially more automated than the current measurement

    jig. Measurements have shown that the accuracy of the method is well within the

    tolerance and that it has a good repeatability.

  • 6.
    Afshar, Reza
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Alavyoon, Navid
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Ahlgren, Anders
    Swedish National Maritime Museums, the Vasa Museum.
    van Dijk, Nico P.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Vorobyev, Alexey
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Gamstedt, Kristofer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    A full-scale finite-element model of the Vasa ship2017In: Proceedings of ECCOMAS Thematic Conference CompWood 2017: Computational Methods in Wood Mechanics, 2017Conference paper (Refereed)
    Abstract [en]

    A full-scale model of the 17th century Vasa shipwreck has been developed to assess its current and future structural stability as well as design an improved support structure. A wireframe model, consisting of only lines, points and curves to describe the geometry of the ship, has been provided by the Vasa museum. It has been developed based on geodetic measurements using a total station. From this wireframe model, a three-dimensional (3D) model comprising solid bodies for solid-like parts (i.e. hull and keel), surfaces for the shell-like components (deck planks) and lines for beam-like constituents (deck beams) has been developed in Creo Parametric 3D software. This geometric model has been imported in finite-element software, Ansys, for further development of the stiffeners (knees, riders, stanchions, masts, etc.), adjustment of the correct location of deck beams and, finally, structural analyses of the entire ship (Figure 1). The procedure for selection of the different types of elements in the finite-element (FE) model, the definition of orthotropic material properties for the timber structure and preliminary results are discussed in this paper. Experiences drawn from this engineering project may also be useful in development of finite element models for structural assessment of other complex wooden structures in cultural heritage.

  • 7.
    Ahlqvist, Marcus
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences.
    Hamad, Gulnaz
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences.
    Kvalitet och processprestanda inom cementindustrins råmjölstillverkning2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    During this work, one of Europe's most modern cement factories is studied, with the capacity to produce around 2.6 million tons of cement per year. The purpose of the thesis is to describe the variation in the outcome of raw meal and identify which causes of variation are possible to reduce. Involuntary variations in the quality of the input raw meal can result in a lack of clinker quality, which in turn can result in a significant loss of revenue. The work is based on theories relating to Total Quality Management, process management and cement production. A method combination of quantitative and qualitative methods has been applied for data collection and data analysis, where the quantitative data collection is based on historical data gathered from the reference organization. The conclusions outlined are that the process being studied has the opportunity to perform world-class. The main contributing factor is the method for control where the system lacks control limits that lead to over compensation. Also, material variation in the case of changes of raw material piles is a significant cause of the variance in the raw meal. Provided that the control system is switched on prematurely after a raw material pile change has been carried out, the effect of the change can be worsened. Furthermore, the results indicate that 80% of the total variation in the raw meal’s lime saturation is created by raw material pile changes.

  • 8.
    Ahmad, Haseeb
    Gotland University, School of Culture, Energy and Environment.
    Offshore Wind Park Connection to an HVDC Platform, without using an AC Collector Platform2012Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis investigates the comparison between two different alternating current topologies of an offshore wind farms connection to an offshore high voltage direct current (HVDC) converter platform. The offshore high voltage direct current converter platform converts alternating current into direct current. Two different topologies will be investigated.

    In the first topology, the offshore wind farms are connected to an HVDC converter platform through offshore AC collector platform. An offshore AC collector platform is used to collect energy from the wind farm and step up the voltages for transmission to HVDC convertor platform. The offshore AC collector platforms contribute significantly in the total cost and technical complexity of the HVDC connection.

    In the second topology, the offshore AC collector platform is removed from the circuit and the offshore wind farms are connected directly to offshore HVDC converter platform.

    In this thesis, short circuit analysis and loss analysis of an offshore wind farm cluster connected to an offshore HVDC converter platform is conducted for the two topologies described above.

    Two wind turbine generator types i.e. doubly fed induction generator and full conversion generator is compared for two different topologies. The effect of changing the distance between wind farms and offshore HVDC converter platform on short circuit currents in the absence of AC collector platform is presented for the second configuration. Two internal voltage levels i.e. 33 kV and 66kV of wind farms are compared for short circuit currents in the absence of AC collector platform. DIgSILENT software is used to perform short circuit calculations.

    The thesis is done in collaboration with “Offshore Wind Connections” department ABB, Sweden. The idea is still under development however this study will serve as good starting point to figure out the cost efficient AC topology of an offshore wind park HVDC connection.

  • 9.
    Ahnesjö, Magnus
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Andersson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Le Corre, Jean-Marie
    Westinghouse Electric Sweden AB.
    Andersson, Stig
    Westinghouse Electric Sweden AB.
    Tomographic reconstructions and predictions of radial void distribution in BWR fuel bundle with part-length rods2015Conference paper (Refereed)
    Abstract [en]

    The Westinghouse FRIGG facility, in Västerås/Sweden, is dedicated to the measurement of critical power,stability and pressure drop in fuel rod bundles under BWR operating conditions (steady-state andtransient). Capability to measure cross-sectional void and radial void distributions during steady-stateoperation was already considered when the facility was built in the late 1960s, using gamma transmissionmeasurements. In the 1990s, redesigned equipment was installed to allow for full 2D tomography andsome test campaigns were successfully run where the void was measured in the Westinghouse SVEA-96fuel bundle geometry with and without part-length rods.

    In this paper, the tomographic raw data from the SVEA-96 void measurement campaigns are revisitedusing various tomographic reconstruction techniques. This includes an algebraic method and a filteredback-projection method. Challenges, for example due to artifacts created by high difference in gammaabsorption, or to accurately identify the location of the bundle structure, are resolved. The resultingdetailed void distributions are then averaged over entire sub-channels or within the steam core only, forcomparison against sub-channel simulations.

    The resulting void distributions are compared against sub-channel void predictions using the VIPREW/MEFISTO code. The region downstream the part-length rods are of particular interest to investigatehow the void in the steam core is redistributed within the open region of the bundle. The comparisonshows a reasonable agreement between the measurements and the predictions.

  • 10.
    Aihara, Aya
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Uzunoğlu, Bahri
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity. Florida State Univ, Dept Math, Tallahassee, FL, USA.
    Vortex induced vibration energy extraction modeling via forced versus free vibration2017In: Proceedings Of Oceans 2017 - Aberdeen, IEEE, 2017Conference paper (Refereed)
    Abstract [en]

    Vortex induced vibrations (VIV) for energy extraction have been revisited in last years by both marine power and wind power communities. Even though vortex induced vibrations have been focus of research for many years, energy extraction from vortex induced vibrations is relevantly new field which needs more detailed investigation and modeling. To this end, there has been recent experimental and modeling parametric studies where VIV was modeled by solution of one-degree-of-freedom ordinary differential equation spring system where engineering modeling of vortex induced vibration for energy extraction has been investigated based on a spring system with the forces defined from forced oscillation experiments where full coupling of free oscillations were not taken into account. Herein a Computational Fluid Dynamics (CFD) modeling of a circular cylinder will be studied to compare forced and free vibrations in the context of vortex-induced energy extraction. The model is essentially solved by partial differential isothermal incompressible Navier-Stokes equations to model fully mathematical model of the fluid-structure interaction of vortex induced vibration. The comparison between forced and free oscillation response studies of this paper will serve to improve the scientific knowledge where vortex induced vibration modeling are comparatively more limited. The preliminary results are presented herein for forced and free oscillations for the Reynolds number regimes Re = 100 and Re = 3800 in two dimensions for combinations of amplitudes and frequency of oscillations in the context of energy extraction modeling.

  • 11.
    Aiso, Toshiharu
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Wiklund, Urban
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Kubota, Manabu
    Nippon Steel & Sumitomo Metal Corporation.
    Jacobson, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Influence of Mn and Al additions to carbon steel on material transfer and coating damage mechanism in a sliding contact between steel and TiN coated HSS tool2016In: Tribology International, ISSN 0301-679X, E-ISSN 1879-2464, Vol. 101, p. 414-424Article in journal (Refereed)
    Abstract [en]

    A crossed cylinders sliding test, simulating the contact between the chip and the cutting tool, is used to evaluate material transfer, friction characteristics and coating damage of a TiN coated high speed steel against specifically designed model steels. These steels include one reference with C as the only alloy element (Base steel), and two alloyed also with 1 mass% Mn or Al. When sliding against the Base steel, an Fe–O layer forms on the coating and protects it from wear. Against the Mn alloyed steel, Fe–Mn–O forms, which has no protective effect. Against the Al alloyed steel, an almost pure Al–O layer forms. This leads to the highest friction, rapidly causing substrate softening and coating fracture.

  • 12.
    Alm, Tobias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences.
    Energieffektivisering av Saltsjöbaden Grand Hotell2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In a hotel building there are many processes which consume energy, such as lightning and drive fan motor in the ventilation system. These processes needs supplied with electricity. The building is a big consumer of heat. The heating system is supplied with heat pumps and oil. The consumption of electricity is about 1700 MWh and 350 MWh of oil. This thesis affects an energy saving investigation for a hotel and the purpose is to find measures to reduce the energy consumption for this building. The method for the investigation consisted of three steps. First step was to establish how much energy the building consumes today. Second step was to find measures which could be implemented and the third was to calculate the energy saving potential for each measure. If all investigated measures will be implemented the Hotel could save up to 40 % energy. If only the economical and easy measures would be implemented the hotel could save 30 % energy. The easiest measure was to change some parameters in the control system so the oil burners did not go at all times. With that change and a change in the control system for ventilation to reduce the hours the ventilation are on gave reduced energy consumption with 20 %. The economical investments were converting one of the oil burners to an extra heat pump and to change all old lighting to a new LED-Lighting.

  • 13.
    Andersson, Gustav
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Industrial Engineering & Management.
    Joneby, Cecilia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Industrial Engineering & Management.
    Automatisering av mätningar i processindustri: Inline-mätning av syrgas i lösning och konduktivitet vid framställning av parenteral nutrition2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In line with technological sensor developments, the possibility of making online qualitycontrols or fluid processes also increases. Two of these controls have beeninvestigated in this project, namely measurement of oxygen in liquid as well as controlof conductivity after completion of the clean in place. The issues are "what sensorsand opportunities are available in the market to enable automation of thesecontrols?", and "how can sensors be implemented in the production process and whatprofits can be made?"The aim of the thesis work is to present what possibilities and limitations there arefor the purchase of sensors in order to enable automation of the measurementsmentioned in the problem description, as well as to suggest sensors and to developlayout proposals in order to describe where in the process the controls are to beimplemented and what impact they have.Several sensors were found, and two of these are considered best suited forintroducing at the factory in the field of pharmaceutical production where the thesishas been carried out. Considering the time aspect and the complexity involved inmanufacturing, the work has been limited due to an implementation is notconceivable.A process flow analysis, literature studies, interviews and a selection have resulted ina situation assessment, market research and a layout proposals. This has then beenanalyzed and the different solutions have been ranked, mapping of profits andproposals for working methods for implementation.Finally, the conclusion was that the two selected sensors are possible to beimplement. Automating these controls involves a number of benefits such asimproved work environment, reduced waste and financial gains. The implementationshould not adversely affect the process, and it would be an appropriate step towardsfurther digitization and Industry 4.0.

  • 14. Andersson, Hjalmar
    et al.
    Zdansky Cottle, Leo
    Claesson, Melker
    Karlsson, Nils
    Stenhammar, Oscar
    Insamling av drift- och produktionsdata från energiteknik vid Ihus anläggning på Vaksala-Eke2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    För att minska den globala uppvärmningen bär utbyggnaden av förnybar energiproduktion en stor vikt i dagens samhälle. Av den anledningen är det av stor betydelse som nya tekniker för energiproduktion testas. För att undersöka huruvida dessa tekniker är effektiva och lönsamma är det viktigt att deras produktionsdata publiceras och görs tillgänglig för allmänheten. Det är anledningen till att det här projektet beställts från Ihus via STUNS energi.

    Projektidén var att samla in högfrekvent uppmätt produktionsdata från en soltracker, ett vindkraftverk och ett batterilager. Dessutom skulle väderdata samlas från en väderstation och solinstrålningsmätare för att sedan offentliggöra datan via STUNS Energiportal.

    För genomförandet av projektet användes en enklare dator för att ta emot information från olika sensorer. För att kommunicera med enheterna användes olika standardiserade kommunikationsprotokoll. Enheterna konfigurerades och kopplades in i datorn. Den insamlade datan bearbetades med en programmerad kod. Programmet sände iväg datan till en molnlagringsplattform för att sedan publicera den.

    Uppkoppling mot soltrackerns växelriktare samt pyranometern lyckades. Den insamlade informationen från de två enheterna publicerades sedan på Energiportalen. Väderstationen producerade data men kommunikation med det ursprungligt tänkta protokollet lyckades inte att upprättas. Genom ett annat protokoll erhölls värden, men inte genom den implementerade koden. Dessutom uppstod problem med batterilagret och vindkraftverket. Ingen information lyckades hämtas från någon av dem.

    I projektets gång har det samlats in mätpunkter var femte sekund för respektive enhet. Utifrån det erhållna resultatet kan de konstateras att vid högfrekvent insamling av väder- och produktionsdata, blir viktig information tydligare för vardera energiproduktionsenhet. Denna information kan gå förlorad vid lågfrekvent datainsamling. Det beror på vädrets hastiga fluktuation. En lågfrekventare datainsamling ger således en sämre uppfattning av hur värdena egentligen ändras med tiden.

  • 15.
    Andersson, Jesper
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences.
    Drumtest: Ett verktyg för testkörning av cykelfälgar2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis you will be able tofollow the design work of a drumtest. A tool that by having a rotatingdrum with equally positioned obstacleswill simulate the conditions a mountainbike rim will pass through.Initially there is a specification ofsome parameters and requirements thatthe design had to fulfill. There is alsosome brief background information aboutwhy a drum test is required for abicycle rim manufacturers and about thecompany Innolite Design AB that thisthesis is done for. After that itfollows an extract from conceptgeneration with the chosen concepts andsolutions but also some of the conceptsthat were not chosen.The thesis also contain a part where thereader cangain a deeper understanding of how thedesign works as well as some moredetailed facts about how the choice ofmaterials, their thicknesses, etc. havebeen made. Finally, one finds the actualresults of this thesis. A complete setof drawings and the information requiredfor building a drum test. The annexesalso include a cost and weightspreadsheet where you easily can seewhich parts costs, and weighs the most.

  • 16.
    Andersson, Malin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Energy storage solutions for electric bus fast charging stations: Cost optimization of grid connection and grid reinforcements2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This study investigates the economic benefits of installing a lithium-ion battery storage (lithium iron phosphate, LFP and lithium titanate, LTO) at an electric bus fast charging station.  It is conducted on a potential electric bus system in the Swedish city Västerås, and based on the existing bus schedules and routes as well as the local distribution system. The size of the energy storage as well as the maximum power outtake from the grid is optimized in order to minimize the total annual cost of the connection. The assessment of the distribution system shows that implementing an electric bus system based on opportunity charging in Västerås does not cause over-capacity in the 10 kV grid during normal feeding mode. However, grid reinforcements might become necessary to guarantee potential backup feeding modes. Batteries are not a cost effective option to decrease grid owner investments in new transformers. However, battery energy storage have the possibility to decrease the annual cost of connecting a fast charging station to the low-voltage grid. The main advantage of the storage system is to decrease the fees to the grid owner. Of the studied batteries, LTO is the most cost effective solution because of its larger possible depth-of-discharge for a given cycle life. The most important characteristics, that determine if a fast charging station could benefit economically from an energy storage, is the bus frequency. The longer the time in between buses and the higher the power demand, the more advantageous is the energy storage.

  • 17.
    Andersson, Martin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Mårtensson, Gustav
    Mycronic AB, Täby.; Chalmers Univ Technol, MC2, EMSL, Gothenburg.
    Klintberg, Lena
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Flowing and pressurizing a solid-liquid two phase monodispersed fluid with high solid content in a transparent microfluidic high-pressure chip2017In: 28TH MICROMECHANICS AND MICROSYSTEMS EUROPE WORKSHOP, IOP PUBLISHING LTD , 2017, article id UNSP 012010Conference paper (Refereed)
    Abstract [en]

    Handling highly concentrated solid-liquid two-phase fluids in microfluidics is challenging. In this paper, we present the first studies of flowing solder paste with a high solid content in a transparent high-pressure tolerant glass chip, thereby increasing the understanding of how multiphase liquids with high density difference between the phases behave in small channels (840 mu m in diameter). The system, including a custom made high-pressure, low resistance, interface, was continuously operated at pressures up to of 6 MPa and devices where shown to have pressure tolerance up to 17 MPa. During flow through the chip, the packing density of the solder balls displayed inhomogeneity over the channel where chains of solder balls in contact with each other were formed together with voids. These in-homogeneities persisted along the channel during flow. The flow rate of the paste through the chip oscillated between 63 to 350 mu m/s when pumping at constant volume rate of 30 mu l/min. When a pressure of 2 MPa was applied, the volume of the solder paste particle segment decreased 1.6%, and 0.1% was elastically recovered when the pressure was released. It is concluded that this transparent microfluidic high-pressure glass chip with the special developed interface is suitable for flow studies of solder paste with a high solid content.

  • 18.
    Andersson, Peter
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Holcombe, Scott
    OECD Halden Reactor Project.
    Tverberg, Terje
    Halden Reactor Project.
    Quantitative Gamma Emission Tomography Inspection of LOCA rod IFA-650.152017In: EHPG, 2017Conference paper (Refereed)
  • 19.
    Andersson, Vincent
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Industrial Engineering & Management.
    Förstude för automationslösning av fönstermontering inom prefabricerad hustillverkning2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of the study is to evaluate the possibilities in implementingan automated solution for the window assembly in prefabricated housingproduction as well as to formulate a layout for such a system. Datacollection have mainly been performed through literature studies,interviews and by the study of provided documentation. The factory in which the suggested cell is to be placed is located inSkaraborg, Sweden, where the main output consists of wall components.The designated area for the robot cell is around 36 square meters. Themain task of the system is to assembly four wooden joists togetherwith a window. Several problems have been identified such as windowssometimes arriving at an undesired orientation as well as a highpayload due to the dimensions of larger window components. A layout with the robot fixated in the middle of the cell has beenrecommended. Software such as Solidworks and RobotStudio have beenused to model and simulate different layout concepts. The suggestedlayout has a cycle time of about four minutes as well as a initialinvestment cost of about 1.22 million Swedish crowns.

  • 20.
    Andreasson, Rebecca
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Visual Information and Interaction. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction. Högskolan i Skövde, Institutionen för informationsteknologi.
    Lindblom, Jessica
    Högskolan i Skövde, Institutionen för informationsteknologi.
    Thorvald, Peter
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Tool use and collaborative work of dock assembly in practice2017In: Production & Manufacturing Research, ISSN 2169-3277, Vol. 5, no 1, p. 164-190Article in journal (Refereed)
    Abstract [en]

    In order to deepen the understanding of the intrinsic interactions and interplay between humans, tools, and environment from a systems perspective, research in the wild (RITW) approaches have gained traction during recent decades as they provide a higher ecological validity of findings. This paper presents a RITW study, investigating how assembly, in this case dock assembly of forwarders, was done in practice. As our theoretical foundation, we used the framework of distributed cognition, which is one of the main pillars of RITW. The findings are presented in narrative form, describing and highlighting that the workers achieve an efficient production outcome by being integral parts of the whole production process and doing so through coordination of activities benefitting the shared goal of the distributed socio-technical system.

  • 21.
    André, Benny
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Jacobson, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Comparisons between commercial low-friction coatings and emerging coating concepts in ball-on-disc tests – coefficient of friction, tribofilm formation and surface damage2008Conference paper (Refereed)
  • 22.
    Angserud, Jenny
    et al.
    Sandvik Mining.
    From, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Wallin, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Jacobson, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Norgren, Susanne
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    On a wear test for rock drill inserts2013Conference paper (Refereed)
    Abstract [en]

    In this work wear of cemented carbide rock drill inserts is evaluated by using a rotating rock cylinder as counter surface. The influence on wear rate and degradation mechanisms from varying dry and wet conditions, cemented carbide grade, abrasive particle type and size as well as load is studied. The used abrasive media are alumina and silica.

    Test results show high repeatability and the three tested cemented carbide grades can be differentiated, even though their relative difference in sample hardness is modest. The loads used, 100–200 N, are sufficiently high to cause fracture and wear of the granite rock. The degraded microstructure of inserts tested under wet and dry conditions as well as with added silica particles is similar to field worn inserts. Hence, the same wear mechanisms occur and the test successfully mimics rock drill wear. Typical insert wear includes cracking and fragmentation of WC grains, depletion of Co binder phase and adhered material originating from the rock.

    Tests under dry conditions always cause less measured wear than tests under wet conditions.

    Addition of alumina particles, which are harder than the used cemented carbide samples, causes a significant wear rate increase but does not provide wear similar to rock drilling.

  • 23.
    Antipova, Kaidi
    Gotland University, Institutionen för humaniora och samhällsvetenskap.
    Flaska för mineralvatten2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this project was to develop a new, more exclusive concept of packaging and labels for mineral water. The main problem with today's bottles for water which we have on the russian market, is that bottles have the same form, are very similar to each other, are intended mainly for the same target group, with sport interests and active way of life and that almost all bottles are made of plastic (PET). The goal for my project is to create a new variant of bottles for water that will be selling to restaurants, café, pubs, fares and other special occasions and to increase value of water through developing a more exclusive product. Using the reference group and studies I have produced a bottle for water which is made of glass, has an aluminium screwing cork and designed label which is different from the other products in the same trade.

  • 24.
    Antonelli, Jacopo
    Gotland University, School of Culture, Energy and Environment.
    Reduced order modeling of wind turbines in MatLab for grid integration and control studies2012Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The current trend in the wind power industry is to develop wind turbines of constantly increasing size and rated power, as well as wind farms of growing size and installed wind power. A careful study of the behaviour of the wind turbines during their operation is of crucial importance in the planning phase and in the design stage of a wind farm, in order to minimize the risks deriving from a non accurate prediction of their impact in the electric grid causing sensible faults of the system.

    To analyze the impact of the wind turbines in the system, motivates the development of accurate yet simple models.

    To be able to practically deal with this topics, a simple model of a wind turbine system is investigated and developed; it has the aim to describe the behaviour of a wind turbine in operation on a mechanical standpoint.

    The same reduced order simple model can also be employed for control system studies; the control system model that can’t be used in generation, can use the reduced model. Together with the analytical description of such model, is realized a MatLab code to numerically analyse the response of the system, and the results of the simulation through such code are presented.

    The objective of this thesis has been to provide a simple benchmark tool in MatLab for grid integration and control studies for interested researchers.

  • 25.
    Ardo, Shane
    et al.
    Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA;Univ Calif Irvine, Dept Chem Engn & Mat Sci, Irvine, CA 92697 USA;US DOE, Off Energy Efficiency & Renewable Energy EERE, Fuel Cell Technol Off, EE-3F,1000 Independence Ave SW, Washington, DC 20585 USA.
    Rivas, David Fernandez
    Univ Twente, MESA Inst Nanotechnol, Mesoscale Chem Syst Grp, Enschede, Netherlands.
    Modestino, Miguel A.
    NYU, Dept Chem & Biomol Engn, Brooklyn, NY 11201 USA.
    Greiving, Verena Schulze
    Univ Twente, Dept Sci Technol & Policy Studies, Enschede, Netherlands.
    Abdi, Fatwa F.
    Helmholtz Zentrum Berlin Mat & Energie GmbH, Inst Solar Fuels, Berlin, Germany.
    Llado, Esther Alarcon
    Amolf Inst, Ctr Nanophoton, Amsterdam, Netherlands.
    Artero, Vincent
    Univ Grenoble Alpes, CNRS, CEA, Lab Chim & Biol Metaux, Grenoble, France.
    Ayers, Katherine
    Proton OnSite, Wallingford, CT 06492 USA.
    Battaglia, Corsin
    Empa, Swiss Fed Labs Mat Sci & Technol, Dubendorf, Switzerland.
    Becker, Jan-Philipp
    Forschungszentrum Julich, IEK Photovolta 5, Julich, Germany.
    Bederak, Dmytro
    Univ Groningen, Zernike Inst Adv Mat, Nijenborgh 4, NL-9747 AG Groningen, Netherlands.
    Berger, Alan
    Air Prod & Chem Inc, Allentown, PA 18195 USA.
    Buda, Francesco
    Leiden Univ, Leiden Inst Chem, Leiden, Netherlands.
    Chinello, Enrico
    Ecole Polytech Fed Lausanne, LAPD, Lausanne, Switzerland.
    Dam, Bernard
    Delft Univ Technol, MECS, Dept Chem Engn, Maasweg 9, NL-2629 HZ Delft, Netherlands.
    Di Palma, Valerio
    Eindhoven Univ Technol, Dept Appl Phys, Eindhoven, Netherlands.
    Edvinsson, Tomas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Fujii, Katsushi
    Univ Kitakyushu, Inst Environm Sci & Technol, Wakamatsu Ku, Kitakyushu, Fukuoka, Japan.
    Gardeniers, Han
    Univ Twente, MESA Inst Nanotechnol, Mesoscale Chem Syst Grp, Enschede, Netherlands.
    Geerlings, Hans
    Delft Univ Technol, MECS, Dept Chem Engn, Maasweg 9, NL-2629 HZ Delft, Netherlands.
    Hashemi, S. Mohammad H.
    Ecole Polytech Fed Lausanne, Opt Lab LO, Lausanne, Switzerland.
    Haussener, Sophia
    Ecole Polytech Fed Lausanne, LRESE, Lausanne, Switzerland.
    Houle, Frances
    Lawrence Berkeley Natl Lab, Joint Ctr Artificial Photosynthesis & Chem Sci Di, Berkeley, CA 94720 USA.
    Huskens, Jurriaan
    Univ Twente, MESA Inst Nanotechnol, Mol Nanofabricat Grp, Enschede, Netherlands.
    James, Brian D.
    Strateg Anal Inc, Arlington, VA 22203 USA.
    Konrad, Kornelia
    Univ Twente, Dept Sci Technol & Policy Studies, Enschede, Netherlands.
    Kudo, Akihiko
    Tokyo Univ Sci, Fac Sci, Dept Appl Chem, Tokyo 1628601, Japan.
    Kunturu, Pramod Patil
    Univ Twente, MESA Inst Nanotechnol, Mol Nanofabricat Grp, Enschede, Netherlands.
    Lohse, Detlef
    Univ Twente, MESA Inst Nanotechnol, Phys Fluids Grp, Enschede, Netherlands.
    Mei, Bastian
    Univ Twente, MESA Inst Nanotechnol, Photocatalyt Synth Grp, Enschede, Netherlands.
    Miller, Eric L.
    Moore, Gary F.
    Arizona State Univ, Sch Mol Sci, Biodesign Ctr Appl Struct Discovery CASD, Tempe, AZ 85287 USA.
    Muller, Jiri
    Inst Energiteknikk, Kjeller, Norway.
    Orchard, Katherine L.
    Univ Cambridge, Dept Chem, Cambridge, England.
    Rosser, Timothy E.
    Univ Cambridge, Dept Chem, Cambridge, England.
    Saadi, Fadl H.
    CALTECH, Div Engn & Appl Sci, Pasadena, CA 91125 USA.
    Schuttauf, Jan-Willem
    Swiss Ctr Elect & Microtechnol CSEM, PV Ctr, Neuchatel, Switzerland.
    Seger, Brian
    Tech Univ Denmark DTU, Dept Phys, Lyngby, Denmark.
    Sheehan, Stafford W.
    Catalyt Innovat, Fall River, MA 02723 USA.
    Smith, Wilson A.
    Delft Univ Technol, MECS, Dept Chem Engn, Maasweg 9, NL-2629 HZ Delft, Netherlands.
    Spurgeon, Joshua
    Univ Louisville, Conn Ctr Renewable Energy Res, Louisville, KY 40292 USA.
    Tang, Maureen H.
    Drexel Univ, Chem & Biol Engn, Philadelphia, PA 19104 USA.
    van de Krol, Roel
    Helmholtz Zentrum Berlin Mat & Energie GmbH, Inst Solar Fuels, Berlin, Germany.
    Vesborg, Peter C. K.
    Tech Univ Denmark DTU, Dept Phys, Lyngby, Denmark.
    Westerik, Pieter
    Univ Twente, MESA Inst Nanotechnol, Mesoscale Chem Syst Grp, Enschede, Netherlands.
    Pathways to electrochemical solar-hydrogen technologies2018In: Energy & Environmental Science, ISSN 1754-5692, E-ISSN 1754-5706, Vol. 11, no 10, p. 2768-2783Article, review/survey (Refereed)
    Abstract [en]

    Solar-powered electrochemical production of hydrogen through water electrolysis is an active and important research endeavor. However, technologies and roadmaps for implementation of this process do not exist. In this perspective paper, we describe potential pathways for solar-hydrogen technologies into the marketplace in the form of photoelectrochemical or photovoltaic-driven electrolysis devices and systems. We detail technical approaches for device and system architectures, economic drivers, societal perceptions, political impacts, technological challenges, and research opportunities. Implementation scenarios are broken down into short-term and long-term markets, and a specific technology roadmap is defined. In the short term, the only plausible economical option will be photovoltaic-driven electrolysis systems for niche applications. In the long term, electrochemical solar-hydrogen technologies could be deployed more broadly in energy markets but will require advances in the technology, significant cost reductions, and/ or policy changes. Ultimately, a transition to a society that significantly relies on solar-hydrogen technologies will benefit from continued creativity and influence from the scientific community.

  • 26.
    Aslam, Tehseen
    et al.
    Univ Skovde, Dept Engn Sci, S-54128 Skovde, Sweden.
    Syberfeldt, Anna
    Univ Skovde, Dept Engn Sci, S-54128 Skovde, Sweden.
    Ng, Amos
    Univ Skovde, Dept Engn Sci, S-54128 Skovde, Sweden.
    Pehrsson, Leif
    Univ Skovde, Dept Engn Sci, S-54128 Skovde, Sweden;Volvo Car Engine, Mfg Res & Concepts, Kaplansgatan 16, S-54143 Skovde, Sweden.
    Moris, Matias Urenda
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Industrial Engineering & Management.
    Towards an Industrial Testbed for Holistic Virtual Production Development2018In: ADVANCES IN MANUFACTURING TECHNOLOGY XXXII / [ed] Thorvald, P Case, K, IOS PRESS , 2018, p. 369-374Conference paper (Refereed)
    Abstract [en]

    Virtual production development is adopted by many companies in the production industry and digital models and virtual tools are utilized for strategic, tactical and operational decisions in almost every stage of the value chain. This paper suggest a testbed concept that aims the production industry to adopt a virtual production development process with integrated tool chains that enables holistic optimizations, all the way from the overall supply chain performance down to individual equipment/devices. The testbed, which is fully virtual, provides a mean for development and testing of integrated digital models and virtual tools, including both technical and methodological aspects.

  • 27.
    Aspsjö, Philip
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Industrial Engineering & Management.
    Spännkraft på bandavskrapare: Utredning och konstruktion2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis was performed at Vendig AB which is a company that develops and sells products such as belt scrapers for conveyor. The thesis is divided into two parts, one part where it´s investigated which tension force is required to tighten Vendig AB´s scraper Hampus against the belt in a correct way. The second part is called mechanical design and here a new and more compact tension device is developed.

    Field studies has been conducted at a couple of Vendig AB´s costumers to get a knowledge base about how Vendig AB´s products are used, how they function and the environment they operate in. During one of the field studies the force between the scraper and the belt was measured. The result from the measurements, together with a report from LKAB [1], were evaluated and summarized in a table. The required force was recalculated for all different version of the scraper.

    After the tension force had been investigated the old tension device was evaluated and a requirement specification for a new was compiled in collaboration with Vendig AB´s group of technology. A number of concepts where then developed using the concept generator tool SCAMPER. One concept conformed very well to the requirement specification and was further developed. The concept was dimensioned by simulations in CAD, and basic drawings were made. The design solutions where discussed with suppliers and the design was updated. Finally a prototype was ordered to test and evaluate the concept. The tests revealed shortcomings in the prototype which has been evaluated and solutions has been discussed.

  • 28.
    Au-Yeung, Ginsun
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences. Uppsala universitet.
    Andersson, Mattias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences. Uppsala universitet.
    How can Lean contribute to create effective meetings?: A case study at Ericsson in Borås2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Lean is a philosophy that has been studied extensively in recent years, and it has been successfully implemented in a number of different processes and businesses. This study aims to examine how Lean can contribute to create effective meetings, which is a topic that has received limited attention in today’s research.

    Firstly, a situation analysis is done in order to identify common meeting problems at Ericsson Borås. Secondly, a comprehensive analysis is conducted concerning whether Lean is applicable on meeting processes or not. This analysis is mainly based on the five principles of Lean Thinking. Thirdly, the study investigates the potential effect of an implementation of Lean, as well as how Lean principles can be applied in order to reduce or eliminate wastes.

    The result of the analysis formed the base for the development of the action plan. Subsequently, the action plan is implemented on the meeting processes by pilot testing it on three different meetings. This analysis is mainly focusing on whether the meeting problems have been eliminated or not.

    Based on our research, we have perceived that almost every meeting is unique and all meeting problems we have identified do not occur at all meetings. Majority of the meeting problems were eliminated by applying Lean principles. Moreover, several respondents also expressed that Lean is a good way to give more structure to meetings, and therefore contributes to more effective meetings. However, we have noticed that principles of Lean cannot eliminate all meeting problems at Ericsson. This can be seen as minor criticism when organizations use Lean as the only solution to improve meeting processes.

  • 29.
    Avelin, Benny
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics.
    Kuusi, Tuomo
    Aalto Univ, Dept Math & Syst Anal, POB 11100, Aalto 00076, Finland..
    Mingione, Giuseppe
    Univ Parma, Dipartimento Matemat & Informat, Parco Area Sci 53-A, I-43124 Parma, Italy..
    Nonlinear Caldern-Zygmund Theory in the Limiting Case2018In: Archive for Rational Mechanics and Analysis, ISSN 0003-9527, E-ISSN 1432-0673, Vol. 227, no 2, p. 663-714Article in journal (Refereed)
    Abstract [en]

    We prove a maximal differentiability and regularity result for solutions to nonlinear measure data problems. Specifically, we deal with the limiting case of the classical theory of Caldern and Zygmund in the setting of nonlinear, possibly degenerate equations and we show a complete linearization effect with respect to the differentiability of solutions. A prototype of the results obtained here tells for instance that ifwith being a Borel measure with locally finite mass on the open subset and , thenThe case is obviously forbidden already in the classical linear case of the Poisson equation.

  • 30.
    Axelsson Paulsson, Victor
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Industrial Engineering & Management.
    Konstruktion av dumpervagn: Från beställning till underlag2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis describes the design of a tipping trailer, from a company’s demands andrequests to complete manufacturing documentation. The design is developed for thecompany Abexor AB in Östersund that produces tipping trailers. The product issupposed to be used by Abexors customer to transport cargos of different kinds,such as gravel, stone, dirt, etc.The work commenced with a meeting at the company where demands were set.After that a pre-study was conducted to find out what traffic rules were required forthe trailer to be allowed to be driven on roads. Similar products were examined tosee how the trailer could be designed. The pre-study was followed by an idea andconcept generation. Nine different concepts were generated and the best werechosen for continued work.The concepts that were chosen resulted in a design in CAD were considerationswere taken for dimensions, traffic rules and function. Manufacturing documentationand a list of components to be bought were generated.In the section discussion and conclusions you can see what the thesis has resulted in.It’s also described what could have been done different and guidelines for futuredevelopment have been made.

  • 31.
    Aydin, Murat
    et al.
    Bochum Univ Appl Sci, Int Geothermal Ctr, D-44801 Bochum, Germany;Istanbul Tech Univ, Energy Inst, TR-34469 Istanbul, Turkey.
    Onur, Mustafa
    Univ Tulsa, McDougall Sch Petr Engn, Tulsa, OK 74104 USA.
    Sisman, Altug
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory. Istanbul Tech Univ, Energy Inst, TR-34469 Istanbul, Turkey.
    A new method for analysis of constant-temperature thermal response tests2019In: Geothermics, ISSN 0375-6505, E-ISSN 1879-3576, Vol. 78, p. 1-8Article in journal (Refereed)
    Abstract [en]

    In this study, a new analysis method is proposed for estimating thermal conductivity of a ground by using the constant-temperature thermal response test data. The new method is based on an analytical solution of heat transfer rate per unit borehole length by using the Laplace transformation for constant-temperature thermal response tests. Its advantage is that it allows one to estimate thermal conductivity directly from the slope of the logarithmic time dependency of inverse unit-heat-transfer rate value without making an estimation of volumetric heat capacity. The method has been verified by using a numerical model and applied to different experimental data based on different test temperatures and compared with the classical thermal response test method. The results show that the proposed method reliably and effectively estimates thermal conductivity of ground.

  • 32.
    Aydin, Murat
    et al.
    Istanbul Technical University, Energy Institute.
    Sisman, Altug
    Istanbul Technical University, Energy Institute.
    Experimental and computational investigation of multi U-tube boreholes2015In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 145, p. 163-171Article in journal (Refereed)
    Abstract [en]

    In ground source heat pump (GSHP) applications, borehole drilling cost constitutes an important part ofthe investment cost and it can be reduced by improving borehole performance. In vertical GSHP applications,usually double-U tube configurations are used to improve the heat transfer rate per unit length of aborehole, (unit HTR value). To determine the optimal number of U-tubes which maximizes the commercialand engineering benefits of multi U-tube applications, cost and performance analyses of multi U-tubeboreholes are crucial. In this study, a triple U-tube is used in a borehole of 50 m depth. Time variation ofunit HTR value of the borehole is experimentally measured when single, double and triple U-tubes are inoperation separately. Furthermore a computational model is calibrated by fitting the computationalresults to the experimental ones, and effects of using four and five U-tubes in a borehole are computationallyinvestigated. The relations between number of U tubes and time variation of unit HTR value ofa borehole as well as investment cost are analyzed. Long term borehole performance predictions aremade and compared for multi U-tube applications. Both experimental and computational results showedthat performance improvements are remarkable for 2U-tube and 3U-tube configurations while it isnearly insignificant for 4U and 5U ones. If the investment cost per thermal power is considered, 2U-tubeconfiguration is the optimal one if the prices of polyethylene pipes are relatively high, like in Turkey.When the cost of pipes decreases, then 3U-tube or even 4U–tube configuration can be the cheapestsolution.

  • 33.
    Ayob, Mohd Nasir
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity. Univ Malaysia Perlis, Sch Mechatron Engn, Arau 02600, Perlis, Malaysia.
    Castellucci, Valeria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Göteman, Malin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Widén, Joakim
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Abrahamsson, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Engström, Jens
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Waters, Rafael
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Small-Scale Renewable Energy Converters for Battery Charging2018In: Journal of Marine Science and Engineering, E-ISSN 2077-1312, Vol. 6, no 1, article id 26Article in journal (Refereed)
    Abstract [en]

    This paper presents two wave energy concepts for small-scale electricity generation. In the presented case, these concepts are installed on the buoy of a heaving, point-absorbing wave energy converter (WEC) for large scale electricity production. In the studied WEC, developed by Uppsala University, small-scale electricity generation in the buoy is needed to power a tidal compensating system designed to increase the performance of the WEC in areas with high tides. The two considered and modeled concepts are an oscillating water column (OWC) and a heaving point absorber. The results indicate that the OWC is too small for the task and does not produce enough energy. On the other hand, the results show that a hybrid system composed of a small heaving point absorber combined with a solar energy system would be able to provide a requested minimum power of around 37.7W on average year around. The WEC and solar panel complement each other, as the WEC produces enough energy by itself during wintertime (but not in the summer), while the solar panel produces enough energy in the summer (but not in the winter).

  • 34.
    Azamy, Ghulam Mustafa
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Industrial Engineering & Management.
    Konstruktion av kopplingsmeknism för SverigeGrepens skaft2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is about folding an ergonomic stall fork shaft in the middle. Reason for the folding of the shaft is partly a customer wish but the main reason is the high cost of shipping. The cost of shipping will be relatively low if the package size is kept below the size of which the shipping company recommends. If you want to transport a package that is larger than the recommend size, the shipping cost well rise drastically.In this case, the cost of a package with size of one meter is deemed to be a profitable shipping cost. The problem is that the total length of the entire stall fork is 1.5 meters, which increases the shipping cost by about 100 SEK per package. Therefore, the stall fork must be folded in the middle to become cheaper to ship.The task is to get on a good and inexpensive solution to a clutch mechanism that allows customers to very easily and simply connect the two shafts together. Because of the shaft being ergonomic, it reduces physical abrasion damages and therefore is the main selling argument. That’s why it is very important not to bring any changes to the ergonomic design or, in worst case, as little as possible.The result was a coupling out of a polymer material that divides the shaft approximately from the middle, has a low weight and is easy for the consumer to assemble the two parts of the shaft.

    The work was carried out by studies of different couplings to be able to come up with a number of different proposals for splitting of the shaft. Furthermore were different materials closely examined and manufacturing methods that the coupling can be manufactured by.The result was a prototype of coupling out of a polymeric material that divides the shaft approximately in the middle, has a low weight and is easy for the consumer to assemble the two shaft halves. The coupling consists of parts, male, female and a core in the middle to make the link robust.

  • 35.
    Babac, Gulru
    et al.
    Istanbul Technical University, Energy Institute.
    Sisman, Altug
    Istanbul Technical University, Energy Institute.
    Cimen, Tolga
    Istanbul Technical University, Energy Institute.
    Two-dimensional thermal analysis of liquid hydrogen tank insulation2009In: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 34, p. 6357-6363Article in journal (Refereed)
    Abstract [en]

    Liquid hydrogen (LH2) storage has the advantage of high volumetric energy density, whileboil-off losses constitute a major disadvantage. To minimize the losses, complicatedinsulation techniques are necessary. In general, Multi Layer Insulation (MLI) and a Vapor-Cooled Shield (VCS) are used together in LH2 tanks. In the design of an LH2 tank with VCS,the main goal is to find the optimum location for the VCS in order to minimize heatleakage. In this study, a 2D thermal model is developed by considering the temperaturedependencies of the thermal conductivity and heat capacity of hydrogen gas. The developedmodel is used to analyze the effects of model considerations on heat leakagepredictions. Furthermore, heat leakage in insulation of LH2 tanks with single and doubleVCS is analyzed for an automobile application, and the optimum locations of the VCS forminimization of heat leakage are determined for both cases.

  • 36.
    Backlund, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Industrial Engineering & Management.
    Transportsimulering för påsar: utvärdering av påsars hållbarhet mot veckning2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis results from the existing test machines that Fresenius Kabi AB, Uppsala, uses today have been compared with the complaints that the customers returns to the company. By this the differences between the damages and holes on the outer pouches of the bags could be found. Two different machines have been used: the shaking table and Gelbo Flex tester. The holes on the pouches were located by filling them with air and put them in water and look for bubbles. A microscope was used to find the reasons behind the wear. The dominating types of wear were creep, abrasive wear and fatigue wear and temperature increase makes the bag even more sensitive for any type of wear. A new type of equipment was built to be able to test the pouches on the shaking table without friction heat. These tests showed much better results that looked more like the complaints. To reduce the number of holes, new designs on the outer pouches were tested. A better design was found by using tables and PUGH-matrix, but some holes were still there. Therefore some calculations were made to get more realistic parameters so the tests got the same severity as a real transport. Some of the parameters were tested to find the ones that get results most similar to a real transport. The new design was then compared with the old one, to see if the difference was big enough to say that the new design is better even in this test. The results showed clearly that the new design was better

  • 37.
    Balint, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Industrial Engineering & Management.
    Beräkning av personslussars mekaniska integritet2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report presents an examination of the mechanical integrity and inspectability of the attachments of man locks in the containment buildings at the Forsmark nuclear power station. The objective of the report is to provide a basis for decisions related to inspection and nondestructive testing of the attachment welds.

    Two mock-ups of the man locks have been manufactured. These have been used for assessing the inspectability of the attachment welds, and for providing test pieces for load tests and reference standards for ultrasonic testing.

    Strength calculations have been performed using the computation program ANSYS 13.0, and based on load tests performed on test pieces from mock-ups. The results of these calculations indicate that the attachment welds can be expected to support the design loads. Tests show that the attachment welds can be inspected with a fiber optical camera.

  • 38.
    Ballaei, Sahar
    Gotland University, School of the Humanities and Social Science.
    Utveckling av skylt samt en parkerings app för Visby innerstad2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this examination project, at candidate level with extent of 15 credits has been going on for ten weeks and been in collaboration with the municipality of Gotland, Region Gotland.This assignment has been about developing a new parking sign for Visby’s inner town and to facilitate navigation in traffic through a parking app. The parking sign and the app interact with each other and create a unity over the traffic problems in Visby.

    The problem formulation of the project has been:“How can I develop a new navigational system to facilitate the traffic flow in Visby and a new parking sign that is easily understood, while blending in with the cultural heritage with reasonable measures for Region Gotland to produce?”

    I have through studies of color, form, function analyzed and come up with a graphic symbol, in a choice that is recognizable to the signs related to parking machines and payment of them adapted for Visby’s inner town as well as it should blend in with the environment. You should easily be able to interpret the signs and find the parking machines as well as the parking app gives you direction to the nearest parking space and inform you if any parking spaces are available or not, all this give you more comprehensive and facilitate information.The project has been adapted to human from an ergonomic perspective and the cultural heritage of Visby old town, with reasonable measures for the municipality to realize and produce.

  • 39.
    Bao, Haiyan
    et al.
    Changsha Univ Sci & Technol, Sch Hydraul Engn, Changsha.; Wuhan Univ, State Key Lab Water Resources & Hydropower Engn S, Wuhan.
    Yang, Jiandong
    Wuhan Univ, State Key Lab Water Resources & Hydropower Engn S, Wuhan.
    Zhao, Guilian
    PowerChina Chengdu Engn Corp Ltd, Chengdu.
    Zeng, Wei
    Wuhan Univ, State Key Lab Water Resources & Hydropower Engn S, Wuhan 430072, Hubei, Peoples R China..
    Liu, Yanna
    Wuhan Univ, State Key Lab Water Resources & Hydropower Engn S, Wuhan.
    Yang, Weijia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity. Wuhan Univ, State Key Lab Water Resources & Hydropower Engn S, Wuhan.
    Condition of setting surge tanks in hydropower plants - A review2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 81, p. 2059-2070Article, review/survey (Refereed)
    Abstract [en]

    Hydropower plays an important role in the safe, stable and efficient operation of power systems, especially with current trends toward renewable energy systems. The total global potential of gross, technical, economic, and exploitable hydropower are still enormous in the future, and the developments of new hydropower stations (HPSs) are of great importance. For constructions of new HPSs, the condition of setting surge tanks (CSST) is crucial for various perspectives, e.g. safety, stability and economy of HPSs. In this review, the CSST are summarized and analyzed from the three aspects: regulation assurance, operation stability, and the regulation quality, with an aim of providing a reference and guidance for research and engineering applications regarding surge tanks. Upstream and downstream surge tanks in conventional HPSs and pumped storage power stations are all included. Moreover, a comprehensive comparison of CSST under different conditions is conducted. One of the main focuses of this review is on Chinese studies, for introducing many meaningful results written in Chinese to more readers all over the world.

  • 40.
    Basirat, Farzad
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Sharma, Prabhakar
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Fagerlund, Fritjof
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Experimental and modeling investigation of CO2 flow and transport in a coupled domain of porous media and free flow2015In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 42, p. 461-470Article in journal (Refereed)
    Abstract [en]

    A solid understanding of the transport mechanisms of gaseous CO2 near the land surface is necessary for developing reliable monitoring techniques and predictive models for possible CO2 leakage from deep underground storage. The objective of this work has been to develop an experimental method along with a simulation model for gaseous CO2 flow and transport in a system including both the porous media and the free air space above it. The experimental system consisted of a two-dimensional bench scale rectangular sandbox containing homogenous sand with an open space of still air above it. Gaseous CO2 was injected in different modes and the CO2 breakthrough was measured on specified ports in the system by using CO2 concentration sensors. A numerical model combining the gas flow in the porous medium and the free flow region was developed and used to model the experimental data. In this quest, the Discontinuous One-Domain approach was selected for modeling transport between the free flow and porous regions. The observed and simulated CO2 breakthrough curves both in the dried sand and in the free flow matched very well in the case of uniform injection and satisfactorily even in the case of point injection. Consequently, it seems that the model reasonably matches the observed data in the cases where the boundary condition is well defined. In summary, our results show that the developed experimental setup provides capability to study gaseous CO2 flow and transport in a coupled porous medium - free flow system and that our modeling approach is able to predict the flow and transport in this system with good accuracy.

  • 41.
    Bastholm, Caroline
    et al.
    Högskolan Dalarna, Energiteknik.
    Fiedler, Frank
    Högskolan Dalarna, Energiteknik.
    Techno-economic study of the impact of blackouts on the viability of connecting an off-grid PV-diesel hybrid system in Tanzania to the national power grid2018In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 171, no 1, p. 647-658Article in journal (Refereed)
    Abstract [en]

    National electrification plans for many countries with a low level of electrification promote the implementation of centralized and decentralized electrification in parallel. This paper explores different ways of utilizing an established off-grid PV-diesel hybrid system when the national grid becomes available. This is a rather unique starting point within the otherwise well-explored area of rural electrification. With particular focus on the impact of blackouts in the national grid, we evaluate the economic viability of some alternatives: to continue to use the off-grid micro-grid, to connect the existing micro-grid with or without battery backup to the national grid, or to use the national grid only. Our simulation results in HOMER demonstrate that with a grid without blackouts, there are few benefits to maintain the existing system. Low grid-connection fees, low tariffs and low revenues from selling excess electricity to the grid contribute to this result despite the fact that the system does not carry any investment costs. With a grid with blackouts, it is beneficial to maintain the system. The extent of blackouts and the load on the system determine which system configuration is most feasible. The results make clear the importance of taking blackouts in the national grid into consideration when possible system configurations are being evaluated. This is rarely quantified in studies comparing different electrification alternatives, but deserves more attention.

  • 42.
    Batchuluun, Bolormaa
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Industrial Engineering & Management.
    Development of New Lifting Equipment for VPA Plates2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis explores how to develop new lifting equipment for the membrane and filter plates of the VPA (Metso) machine satisfying all the safety requirements. The VPA is a heavy duty machine with a number of plates, developed for filtration of minerals. The plates must be replaced or removed immediately once the wear has reached a given value or an error has been detected.

    The new lifting system differs to a great extent from conventional system in which a fiber strap was used; the designed lifting equipment comprises of a variety of parts resulting in a higher capacity to be used ín different situations safer and satisfies the vital requirements such as being a secure and cost-effective method, issued by the customers.

    Several solution proposals have been developed to offer better proposals before the final candidate has been selected and theoretically motivated with FEM analysis as well as analytical calculations.

    Keywords - VPA, membrane and filter plate, lifting equipment, pivot supporter hinge, safety, cost effective

  • 43.
    Baudoin, Antoine
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Cooling Strategies for Wave Power Conversion Systems2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The Division for Electricity of Uppsala University is developing a wave power concept. The energy of the ocean waves is harvested with wave energy converters, consisting of one buoy and one linear generator. The units are connected in a submerged substation. The mechanical design is kept as simple as possible to ensure reliability.

    The submerged substation includes power electronics and different types of electrical power components. Due to the high cost of maintenance operations at sea, the reliability of electrical systems for offshore renewable energy is a major issue in the pursuit of making the electricity production economically viable. Therefore, proper thermal management is essential to avoid the components being damaged by excessive temperature increases.

    The chosen cooling strategy is fully passive, and includes no fans. It has been applied in the second substation prototype with curved heatsinks mounted on the inner wall of the pressurized vessel. This strategy has been evaluated with a thermal model for the completed substation. First of all, 3D-CFD models were implemented for selected components of the electrical conversion system. The results from these submodels were used to build a lumped parameter model at the system level.

    The comprehensive thermal study of the substation indicates that the rated power in the present configuration is around 170 kW. The critical components were identified. The transformers and the inverters are the limiting components for high DC-voltage and low DC-voltage respectively. The DC-voltage—an important parameter in the control strategy for the WEC—was shown to have the most significant effect on the temperature limitation.

    As power diodes are the first step of conversion, they are subject to large power fluctuations. Therefore, we studied thermal cycling for these components. The results indicated that the junction undergoes repeated temperature cycles, where the amplitude increased with the square root of the absorbed power.

    Finally, an array of generic heat sources was optimized. We designed an experimental setup to investigate conjugate natural convection on a vertical plate with flush-mounted heat sources. The influence of the heaters distribution was evaluated for different dissipated powers. Measurements were used for validation of a CFD model. We proposed optimal distributions for up to 36 heat sources. The cooling capacity was maximized while the used area was minimized.

    List of papers
    1. Optimized distribution of a large number of heat sources cooled by conjugate turbulent natural convection
    Open this publication in new window or tab >>Optimized distribution of a large number of heat sources cooled by conjugate turbulent natural convection
    (English)In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606Article in journal (Refereed) Submitted
    National Category
    Energy Engineering
    Identifiers
    urn:nbn:se:uu:diva-307944 (URN)
    Available from: 2016-11-24 Created: 2016-11-23 Last updated: 2017-11-29
    2. Temperature and velocity measurements in a buoyant flow induced by a heat source array on a vertical plate
    Open this publication in new window or tab >>Temperature and velocity measurements in a buoyant flow induced by a heat source array on a vertical plate
    2017 (English)In: Experimental Thermal and Fluid Science, ISSN 0894-1777, E-ISSN 1879-2286, Vol. 88, p. 234-245Article in journal (Refereed) Published
    Abstract [en]

    Heat source arrays are common in engineering applications. Natural convection is a reliable and silent cooling strategy. Therefore, an array of flush-mounted heat sources has been studied under conjugate conduction and natural convection condition. This studies was performed for a system with relatively large dimensions, typical for power electronics, and a modified Rayleigh number up to 2 . 10(10) A modular set of heaters was designed to vary the distribution of heat sources on the plate and investigate the influence of the spacing. Velocity and temperature were measured in the convective flow with particle image velocimetry and micro-thermocouple. The velocity field was analyzed with proper orthogonal decomposition. The first instabilities of the convective flows were described. The results gave abetter understanding of the heat transfers in these configurations and are valuable for model validation.

    National Category
    Energy Engineering Fluid Mechanics and Acoustics
    Identifiers
    urn:nbn:se:uu:diva-307943 (URN)10.1016/j.expthermflusci.2017.06.002 (DOI)000409285600023 ()
    Funder
    SweGRIDS - Swedish Centre for Smart Grids and Energy StorageStandUp
    Available from: 2016-11-24 Created: 2016-11-23 Last updated: 2017-12-01Bibliographically approved
    3. Experimental Optimization of Passive Cooling of a Heat Source Array Flush-Mounted on a Vertical Plate
    Open this publication in new window or tab >>Experimental Optimization of Passive Cooling of a Heat Source Array Flush-Mounted on a Vertical Plate
    2016 (English)In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 9, no 11, article id 912Article in journal (Refereed) Published
    Abstract [en]

    Heat sources, such as power electronics for offshore power, could be cooled passively—mainly by conduction and natural convection. The obvious advantage of this strategy is its high reliability. However, it must be implemented in an efficient manner (i.e., the area needs to be kept low to limit the construction costs). In this study, the placement of multiple heat sources mounted on a vertical plate was studied experimentally for optimization purposes. We chose a regular distribution, as this is likely to be the preferred choice in the construction process. We found that optimal spacing can be determined for a targeted source density by tuning the vertical and horizontal spacing between the heat sources. The optimal aspect ratio was estimated to be around two.

    Keywords
    discrete heat sources, source array, natural convection, optimization
    National Category
    Energy Engineering
    Identifiers
    urn:nbn:se:uu:diva-307831 (URN)10.3390/en9110912 (DOI)000388580000054 ()
    Funder
    SweGRIDS - Swedish Centre for Smart Grids and Energy StorageStandUp
    Available from: 2016-11-22 Created: 2016-11-22 Last updated: 2017-11-29Bibliographically approved
    4. Assessment of Thermal Cycling in a Rectifier For WavePower Generation
    Open this publication in new window or tab >>Assessment of Thermal Cycling in a Rectifier For WavePower Generation
    2016 (English)Conference paper, Published paper (Refereed)
    Abstract [en]

    Natural convection allows for passive cooling which isused in many engineering applications. Placing dissipatingcomponents on a common vertical heatsink can be opti-mized to give the best possible cooling capacity. In thisstudy, a numerical model for three-dimensional conjugatedconvective and conductive heat transfer was used to evalu-ate the distribution of up to 36 ush-mounted rectangularheaters. The temperature proles and the heat uxes werecompared with experimental data for validation. The dis-sipated power was set as an input parameter and the op-timal distribution was selected as the one with the lowesttemperature elevation. Two dierent heuristicsa geo-metric parameter and an articial neural networkwereproposed and evaluated as alternatives to heavy CFD cal-culations.

    National Category
    Energy Engineering
    Identifiers
    urn:nbn:se:uu:diva-307945 (URN)
    Conference
    IET Renewable Power Generation
    Available from: 2016-11-23 Created: 2016-11-23 Last updated: 2016-11-25
    5. Thermal Rating of a Submerged Substation for Wave Power
    Open this publication in new window or tab >>Thermal Rating of a Submerged Substation for Wave Power
    2016 (English)In: IEEE Transactions on Sustainable Energy, ISSN 1949-3029, E-ISSN 1949-3037, Vol. 7, no 1, p. 436-445Article in journal (Refereed) Published
    Abstract [en]

    The costs of offshore maintenance operations put high reliability-requirements on offshore equipment for ocean energy, especially on submerged ones. Thermal management is thus essential in the design of the prototypes of a marine substation, developed at Uppsala University, for grid interface of wave power parks. The cooling system itself should be efficient as well as reliable. Therefore, the feasibility of a completely passive cooling strategy was evaluated. The studied substation includes various power components, which dissipate heat and are installed in one pressurized vessel. Thermal cross-coupling was investigated with 3-D submodels and a thermal network model. An electric circuit was coupled to determine the rated power of the substation. The results depend mainly on the dc-voltage, the seawater temperature, and the thermal contact between the components and the hull.

    Keywords
    Computational fluid dynamics;Computational modeling;Heat transfer;Heating;Integrated circuit modeling;Substations;Wave power;Computational fluid dynamic (CFD);natural convection;ocean energy;passive cooling;power electronics;thermal management;wave power
    National Category
    Engineering and Technology Ocean and River Engineering
    Identifiers
    urn:nbn:se:uu:diva-267226 (URN)10.1109/TSTE.2015.2425045 (DOI)000367340700044 ()
    Funder
    SweGRIDS - Swedish Centre for Smart Grids and Energy StorageStandUpSwedish Energy Agency
    Available from: 2015-11-19 Created: 2015-11-19 Last updated: 2017-12-01Bibliographically approved
    6. Thermal modelling of a passively cooled inverter for wave power
    Open this publication in new window or tab >>Thermal modelling of a passively cooled inverter for wave power
    2015 (English)In: IET Renewable Power Generation, ISSN 1752-1416, E-ISSN 1752-1424, Vol. 9, no 4, p. 389-395Article in journal (Refereed) Published
    Abstract [en]

    Owing to very costly maintenance operations, the reliability of electrical systems for offshore renewable energy is a major issue to make electricity production economical. Therefore proper thermal management is essential in order to avoid the components from being damaged by excessive temperature increase. Both analytic and computational fluid dynamics (CFD) models were implemented to assess the temperature increase in the inverter installed in a submerged substation and during working conditions. It was shown that this inverter could transmit a total power of up to about 35 kW. This limit is dependent on a certain distance between the modules and a perfect thermal contact with the hull. The influence of several of such parameters as well as the efficiency of passive cooling were studied.

    Keywords
    wave power plants, invertors, substations, cooling, thermal modelling, passively cooled inverter, wave power, CFD models, submerged substation, thermal contact, passive cooling
    National Category
    Environmental Engineering
    Research subject
    Engineering Science with specialization in Science of Electricity
    Identifiers
    urn:nbn:se:uu:diva-252981 (URN)10.1049/iet-rpg.2014.0112 (DOI)000352809300011 ()
    Available from: 2015-05-19 Created: 2015-05-18 Last updated: 2017-12-04Bibliographically approved
    7. Wave Energy Research at Uppsala University and The Lysekil Research Site, Sweden: A Status Update
    Open this publication in new window or tab >>Wave Energy Research at Uppsala University and The Lysekil Research Site, Sweden: A Status Update
    Show others...
    2015 (English)Conference paper, Published paper (Refereed)
    Abstract [en]

    This paper provides a summarized status update ofthe Lysekil wave power project. The Lysekil project is coordinatedby the Div. of Electricity, Uppsala University since 2002, with theobjective to develop full-scale wave power converters (WEC). Theconcept is based on a linear synchronous generator (anchored tothe seabed) driven by a heaving point absorber. This WEC has nogearbox or other mechanical or hydraulic conversion systems,resulting in a simpler and robust power plant. Since 2006, 12 suchWECs have been build and tested at the research site located atthe west coast of Sweden. The last update includes a new andextended project permit, deployment of a new marine substation,tests of several concepts of heaving buoys, grid connection,improved measuring station, improved modelling of wave powerfarms, implementation of remote operated vehicles forunderwater cable connection, and comprehensive environmentalmonitoring studies.

    Keywords
    Wave energy, point absorber, experiments, arrays, generators, ROVs
    National Category
    Electrical Engineering, Electronic Engineering, Information Engineering Ocean and River Engineering
    Identifiers
    urn:nbn:se:uu:diva-265218 (URN)
    Conference
    Proceedings of the 11th European Wave and Tidal Energy Conference. Nantes, France, September 2015
    Available from: 2015-10-26 Created: 2015-10-26 Last updated: 2019-08-19Bibliographically approved
    8. Measurement System For Wave Energy Converter - Design And Implementation
    Open this publication in new window or tab >>Measurement System For Wave Energy Converter - Design And Implementation
    2014 (English)In: 33Rd International Conference On Ocean, Offshore And Arctic Engineering, 2014, Vol 9A: Ocean Renewable Energy, AMER SOC MECHANICAL ENGINEERS , 2014Conference paper, Published paper (Refereed)
    Abstract [en]

    A Wave Energy Converter (WEC) measurement system has been constructed and installed with the purpose to measure, log and evaluate the WEC's performance during operation at sea. The WEC is to be deployed at Uppsala University's wave power research site in Lysekil on the west coast of Sweden. In designing such a system the key research objectives has been (1) to study the risk of overheating due to high currents in the stator windings, (2) to evaluate how the WEC's outer structure withstands drag and bending forces from the buoy line and (3) to construct a detection system which indicates if water leaks into the generator. The measurement system was designed to collect data essential to study these key objectives. Transducers were used to measure: buoy line force, translator position, phase currents, bending and tensile strain on the generator hull, water level inside generator and the temperature at multiple places inside the generator. The measurement system has been installed and calibrated in the WEC. Furthermore, the design has been evaluated in lab experiments in order to verify the function and accuracy of the different measurements. This paper presents the underlying research objectives for developing the WEC generator measurement system, together with a description of the technical implementation.

    Place, publisher, year, edition, pages
    AMER SOC MECHANICAL ENGINEERS, 2014
    National Category
    Energy Systems Ocean and River Engineering
    Identifiers
    urn:nbn:se:uu:diva-272118 (URN)000363499000005 ()978-0-7918-4553-0 (ISBN)
    Conference
    33Rd International Conference On Ocean, Offshore And Arctic Engineering
    Note

    Första författaren har bytt efternamn till Ulvgård

    Available from: 2016-01-12 Created: 2016-01-12 Last updated: 2017-09-28
    9. Status Update of the Wave Energy Research at Uppsala University
    Open this publication in new window or tab >>Status Update of the Wave Energy Research at Uppsala University
    Show others...
    2013 (English)Conference paper, Published paper (Refereed)
    Place, publisher, year, edition, pages
    Aalborg, Denmark: , 2013
    National Category
    Engineering and Technology
    Research subject
    Engineering Science with specialization in Science of Electricity
    Identifiers
    urn:nbn:se:uu:diva-212701 (URN)
    Conference
    10th European Wave and Tidal Conference (EWTEC)
    Available from: 2013-12-13 Created: 2013-12-13 Last updated: 2017-12-07
    10. Temperature Study in a Marine Substation for Wave Power
    Open this publication in new window or tab >>Temperature Study in a Marine Substation for Wave Power
    Show others...
    2012 (English)In: International Journal of Mechanic Systems Engineering, ISSN 2225-7403, Vol. 2, no 4, p. 126-131Article in journal (Refereed) Published
    National Category
    Engineering and Technology
    Research subject
    Engineering Science with specialization in Science of Electricity
    Identifiers
    urn:nbn:se:uu:diva-190091 (URN)
    Available from: 2013-01-07 Created: 2013-01-07 Last updated: 2017-01-18Bibliographically approved
    11. Marine substation design for grid-connection of a research wave power plant on the Swedish West coast
    Open this publication in new window or tab >>Marine substation design for grid-connection of a research wave power plant on the Swedish West coast
    2013 (English)Conference paper, Published paper (Refereed)
    Place, publisher, year, edition, pages
    Aalborg, Denmark: , 2013
    National Category
    Engineering and Technology
    Research subject
    Engineering Science with specialization in Science of Electricity
    Identifiers
    urn:nbn:se:uu:diva-212687 (URN)
    Conference
    10th European Wave and Tidal Conference (EWTEC)
    Available from: 2013-12-13 Created: 2013-12-13 Last updated: 2016-11-24
    12. Lysekil Research Site, Sweden: A status update
    Open this publication in new window or tab >>Lysekil Research Site, Sweden: A status update
    Show others...
    2011 (English)In: 9th European Wave and Tidal Energy Conference, Southampton, UK, 2011, 2011Conference paper, Published paper (Refereed)
    National Category
    Electrical Engineering, Electronic Engineering, Information Engineering
    Research subject
    Engineering Science with specialization in Science of Electricity
    Identifiers
    urn:nbn:se:uu:diva-160039 (URN)
    Conference
    9th European Wave and Tidal Energy Conference, Southampton, UK, 5-9 September 2011
    Available from: 2011-10-13 Created: 2011-10-13 Last updated: 2017-01-25
  • 44.
    Baudoin, Antoine
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Boström, Cecilia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Saury, Didier
    Assessment of Thermal Cycling in a Rectifier For WavePower Generation2016Conference paper (Refereed)
    Abstract [en]

    Natural convection allows for passive cooling which isused in many engineering applications. Placing dissipatingcomponents on a common vertical heatsink can be opti-mized to give the best possible cooling capacity. In thisstudy, a numerical model for three-dimensional conjugatedconvective and conductive heat transfer was used to evalu-ate the distribution of up to 36 ush-mounted rectangularheaters. The temperature proles and the heat uxes werecompared with experimental data for validation. The dis-sipated power was set as an input parameter and the op-timal distribution was selected as the one with the lowesttemperature elevation. Two dierent heuristicsa geo-metric parameter and an articial neural networkwereproposed and evaluated as alternatives to heavy CFD cal-culations.

  • 45.
    Baudoin, Antoine
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Saury, Didier
    Univ Poitiers, ENSMA, CNRS, Inst PPRIME, BP 40109, F-86961 Futuroscope, France.
    Temperature and velocity measurements in a buoyant flow induced by a heat source array on a vertical plate2017In: Experimental Thermal and Fluid Science, ISSN 0894-1777, E-ISSN 1879-2286, Vol. 88, p. 234-245Article in journal (Refereed)
    Abstract [en]

    Heat source arrays are common in engineering applications. Natural convection is a reliable and silent cooling strategy. Therefore, an array of flush-mounted heat sources has been studied under conjugate conduction and natural convection condition. This studies was performed for a system with relatively large dimensions, typical for power electronics, and a modified Rayleigh number up to 2 . 10(10) A modular set of heaters was designed to vary the distribution of heat sources on the plate and investigate the influence of the spacing. Velocity and temperature were measured in the convective flow with particle image velocimetry and micro-thermocouple. The velocity field was analyzed with proper orthogonal decomposition. The first instabilities of the convective flows were described. The results gave abetter understanding of the heat transfers in these configurations and are valuable for model validation.

  • 46.
    Baudoin, Antoine
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Saury, Didier
    Boström, Cecilia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Optimized distribution of a large number of heat sources cooled by conjugate turbulent natural convectionIn: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606Article in journal (Refereed)
  • 47.
    Baudoin, Antoine
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Saury, Didier
    Univ Poitiers, ENSMA, CNRS, Inst PPRIME, BP 40109, F-86961 Futuroscope, Chassencuil, France.
    Zhu, Bo
    Univ Poitiers, ENSMA, CNRS, Inst PPRIME, BP 40109, F-86961 Futuroscope, Chassencuil, France.
    Boström, Cecilia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Experimental Optimization of Passive Cooling of a Heat Source Array Flush-Mounted on a Vertical Plate2016In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 9, no 11, article id 912Article in journal (Refereed)
    Abstract [en]

    Heat sources, such as power electronics for offshore power, could be cooled passively—mainly by conduction and natural convection. The obvious advantage of this strategy is its high reliability. However, it must be implemented in an efficient manner (i.e., the area needs to be kept low to limit the construction costs). In this study, the placement of multiple heat sources mounted on a vertical plate was studied experimentally for optimization purposes. We chose a regular distribution, as this is likely to be the preferred choice in the construction process. We found that optimal spacing can be determined for a targeted source density by tuning the vertical and horizontal spacing between the heat sources. The optimal aspect ratio was estimated to be around two.

  • 48.
    Bee, Elena
    et al.
    Univ Trento, Dept Civil Environm & Mech Engn, Trento, Italy.
    Prada, Alessandro
    Univ Trento, Dept Civil Environm & Mech Engn, Trento, Italy.
    Baggio, Paolo
    Univ Trento, Dept Civil Environm & Mech Engn, Trento, Italy.
    Psimopoulos, Emmanouil
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences. Dalarna Univ, Energy Technol, Borlange, Sweden.
    Air-source heat pump and photovoltaic systems for residential heating and cooling: Potential of self-consumption in different European climates2019In: Building Simulation, ISSN 1996-3599, E-ISSN 1996-8744, Vol. 12, no 3, p. 453-463Article in journal (Refereed)
    Abstract [en]

    Renewable sources will play a key role in meeting the EU targets for 2030. The combined use of an aerothermal source through a heat pump and a solar source with a photovoltaic (PV) system is one feasible and promising technology for the heating and cooling of residential spaces. In this study, a detailed model of a single-family house with an air-source heat pump and a PV system is developed with the TRNSYS simulation software. Yearly simulations are run for two types of buildings and nine European climates, for both heating and cooling (where needed), in order to have an overview of the system behaviour, which is deeply influenced by the climate. The storage system (electrical and thermal) is also investigated, by means of multiple simulation scenarios, with and without the battery and with different water storage sizes. The numerical results provide an overview of the performance of the considered heating and cooling system, as well as the balance of the electrical energy exchange between the grid, the building, and the PV array.

  • 49.
    Bejhed, Johan
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Materials Science. ÅSTC.
    Eriksson, Anders
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Materials Science. ÅSTC.
    Stenmark, L
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Materials Science. ÅSTC.
    The Development of a Micro Machined Xenon Feed System2004In: AIAA-2004-3976, 40th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit: Fort Lauderdale, Florida, USA, 11-14 July 2004, 2004, p. pp 1-8Conference paper (Other scientific)
  • 50.
    Bejhed, Johan
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Materials Science. ÅSTC.
    Wallbank, J
    Lindegren, Robert
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Materials Science. ÅSTC.
    Thorslund, Robert
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Materials Science. ÅSTC.
    Baker, A M
    Stenmark, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Materials Science. ÅSTC.
    Köhler, Johan
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Materials Science. ÅSTC.
    Catalyst microsystem design and manufacture for a monopropellant microrocket engine2004In: PowerMEMS 2004, Kyoto, Japan.: 28-30 November, 2004., 2004Conference paper (Other scientific)
1234567 1 - 50 of 833
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