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  • 151.
    David, Andrei
    et al.
    Aalborg Univ, Dept Planning, Copenhagen, Denmark.
    Vad Mathiesen, Brian
    Aalborg Univ, Dept Planning, Copenhagen, Denmark.
    Averfalk, Helge
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Lund, Henrik
    Aalborg Univ, Dept Planning, Aalborg, Denmark.
    Heat Roadmap Europe: Large-Scale Electric Heat Pumps in District Heating Systems2017In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 10, no 4, article id 578Article in journal (Refereed)
    Abstract [en]

    The Heat Roadmap Europe (HRE) studies estimated a potential increase of the district heating (DH) share to 50% of the entire heat demand by 2050, with approximately 25–30% of it being supplied using large-scale electric heat pumps. This study builds on this potential and aims to document that such developments can begin now with technologies currently available. We present a database and the status of the technology and its ability of expansion to other European locations by reviewing experiences aimed at further research or application in the heating industry. This is based on a survey of the existing capacity of electric large-scale heat pumps with more than 1 MW thermal output, operating in European DH systems. The survey is the first database of its kind containing the technical characteristics of these heat pumps, and provides the basis for the analysis of this paper. By quantifying the heat sources, refrigerants, efficiency and types of operation of 149 units with 1580 MW of thermal output, the study further uses this data to analyze if the deployment of this technology on a large-scale is possible in other locations in Europe. It finally demonstrates that the technical level of the existing heat pumps is mature enough to make them suitable for replication in other locations in Europe.

  • 152.
    de Beer, Rocco
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Fredriksson, Jakob
    Halmstad University, School of Business and Engineering (SET).
    Analys och kontroll av hållfasthet på grenställsarm2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis was done in collaboration with EAB situated in Smålandsstenar. In the initial discussion faze on doing a thesis with them there was a need to analyze and ensure the strength of an existing product, cantilever racks. This included performing FEM calculations on a model and comparing the results with physical tests.

    EAB has two models of cantilever racks, a light duty and a heavy duty. Within the heavy duty model series there are five product variants that differ in both size and load capacity. We will be working with the product variant with a load capacity of 1000 kg/arm which is the variant that is in the middle of the series.

    When we started work on the thesis we did a literature study and couldn’t find any well defined methodology that integrates both product development and computer aided design analysis. This meant that we had to combine and use both Freddy Olsson’s principle product development and known methods in FEM analysis.

    In the early stages of our work we also came to the conclusion that we need to compare our FEM analysis results to more than solely normal hand calculations, as these take into account many safety factor that will not be included in our computer aided model. So together with EAB we agreed to perform physical tests that will be similar in setup as our FEM analysis, leading to more comparable results.

    FEM analysis was conducted in CATIA V5 Generative Structural Analysis and physical tests were carried out at EAB in their test facility

  • 153.
    Despotovski, Natali
    et al.
    Halmstad University.
    Vuletic, Sonja
    Halmstad University.
    A Product Development of Safety Car Seats for Children2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Car accidents happens daily, and it is very important to protect all involved in a carno matter the age. Persons that are old enough and can take care of themselves, usescar seat belts to be protected in traffic. A child, however, must be placed andfastened in a safety seat by a parent or another caregiver, to be fully protected. Children that are correctly secured in safety seats have a 2.7 times bigger chance tosurvive a car crash without serious injuries compared to unstrained children (Berget al., 2000; WHO,2004). Regardless tests and safety seats that are available ontoday’s market, there are still issues that needs to be eliminated. Daily users of thisproduct are a good starting point since these people want a safe seat for their childthat can be easy to install and affordable; and they can best tell what issues theyencounter.

    Based on several scientific articles in a combination with interviews andobservations, issues with the safety seats could be confirmed. The primary issue isthe seat belt that is attached to the safety seat. Children can develop a habit ofwriggling out of the belt in safety seats. There are belt collectors available on themarket which holds the shoulder belts in place. In this way, it is harder for thechildren to slide out of the belt and helps to keep the belt properly positioned(BeSafe, 2018). Instead of having this as an accessory, it has been considered in thebelt that have been developed. Another issue is that the belt is complicated tofastened since two straps has to be simultaneously clicked in the belt buckle. If thisis done incorrectly, the belt cannot be fastened, and it takes time to try it again. Tomake this easier, two straps and the strap between the child's leg will be fastenedseparately in a seat buckle each. In this way, parents and other caregivers will beable to fasten the belt easy and properly. They will also be sure that the child issafely fastened and will minimize injury during an accident or another situation.

  • 154.
    Deutschmann, Oliver
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Johansson, Thomas
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Framtidens elbilar utmanar nutidens elnät: Påverkan av ett ökat antal elbilar på ett halländskt elnät2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The challenges facing low voltage grids are rising as an increasing number of domestic houses transition from fossil fueled heating to electricity based heating. Several environmental goals and visions have the same transition from fossil based power to electricity based power in mind for the transportation sector. One of the most important tools for this transformation is widely regarded to be the electric vehicle. With the demands of the electric vehicle pressuring the power grid, several questions arise regarding the growth of the electric vehicle market and what repercussions it may have on the grid. This paper focuses on a typical low voltage grid in southern Sweden and what effects a growing electric vehicle market may have on it. Through computer-assisted simulations based on several future scenarios regarding the EV market, this paper finds that few modifications and reinforcements are needed on this particular grid within the next 10 to 15 years. After this timeframe the voltage drop becomes a serious concern and should be addressed.

  • 155.
    Dia, Ali
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Bengtsson, Fredrik
    Halmstad University, School of Business and Engineering (SET).
    Energikartläggning av lagerbyggnad: en kvalitativ studie mot lagerbyggnader inom logistik branschen2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 156.
    Dimkovski, Zlate
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Characterization of Engineering Surfaces Having Linear Features2012In: Proceedings of the 2nd Seminar on Surface Metrology for the Americas, Worcester: Worcester Polytechnic Institute , 2012Conference paper (Refereed)
    Abstract [en]

    There is a variety of engineering surfaces having linear scratches/grooves of different density, width and depth, some parts covered by folded metal, and some parts totally interrupted and unbalanced as a result of the machining or wear process. These grooves are critical for good function of the surface, and need to be quickly and objectively quantified for an efficient surface finish development. A suitable way to do this is to use optical 3D measurements and to combine the profile and image analysis. In this tutorial extraction and quantification of grooves/wear scratches of machined (honed and polished) and worn (honed) surfaces will be presented. In particular, it will be shown how the features, such as width, height, and distance between grooves, honing angle, balance of honing texture, and groove interrupts can be successively characterized.

  • 157.
    Dimkovski, Zlate
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Optimization of the Triboconditioning Process for Low Friction Surfaces2015Conference paper (Refereed)
  • 158.
    Dimkovski, Zlate
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Process Optimization of Low Friction Surfaces in Pin-Roller Contacts2014Conference paper (Refereed)
  • 159.
    Dimkovski, Zlate
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Recent R&D on Engine Cylinders2013Conference paper (Other (popular science, discussion, etc.))
  • 160.
    Dimkovski, Zlate
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Reduced engine friction for low climate impact2014Conference paper (Refereed)
    Abstract [en]

    Reducing friction in the Piston-Cylinder Unit - PCU is one of the priorities in the automotive industry as it is the largest contributor to the frictional losses and hence the fuel consumption of the internal combustion engines. Not only fuel consumption, but also the oil consumption and emissions are largely affected by the piston-ring-liner interactions. Therefore, from an optimized PCU, competitive, economic and environmental benefits would be gained.  In this project, fuel/oil consumption and emissions of car and truck engines were reduced by using different cylinder liner finishes and different ring designs/loads. Experimental and theoretical studies have been performed by simulating and testing the behaviour of various oil control rings and cylinder liner surfaces in reciprocating tribotesters. Several full-scale engine tests were performed to verify the improvements. The engine tests showed up to 1.8% reduction of the fuel consumption while keeping low oil consumption by using smoothly honed liner surfaces and low ring loads/widths. Further reduction of the oil consumption was shown in the tribotests and simulations when textured liner surfaces were used. To accomplish this, a cost-effective texturing process has to be found and to be confirmed in the engine tests.

  • 161.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Anderberg, Cecilia
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Ohlsson, Robert
    Volvo Powertrain Corp., Volvo Group, Göteborg, Sweden.
    Rosén, Bengt - Göran
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Characterisation of worn cylinder liner surfaces by segmentation of honing and wear scratches2011In: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 271, p. 548-552Article in journal (Refereed)
    Abstract [en]

    The presence of the honing scratches/grooves in cylinder liner surfaces is intended and desired as they improve the lubrication and retain the debris reducing the piston assembly/liner friction and consequently improve the fuel economy and longevity of the internal combustion (IC) engines. Axial scratches caused by the abrasive wear between the tribological partners and/or entrained wear particles are undesired since they are correlated with increased oil consumption and noxious emissions of the IC engines. Due to the imperfection of the manufacturing process, the honing grooves, especially the deep ones, are smeared and interrupted by folds. A portion of the folds would eventually detach during the running process and act as abrasive particles increasing the wear in the cylinder. To closely examine the influence of all these features on the liner's function, it emerges a need to objectively quantify the axial wear scratches, plateau honing grooves, deep honing grooves and their interrupts. The existing techniques fail to segment a groove containing interrupts as they usually appear as summits at several locations in the course of the groove. Combining the profile and image analyses, the deep grooves and their interrupts were successfully identified and quantified in earlier works of the authors. In this paper those algorithms are extended, so that the deep honing grooves, plateau honing grooves and axial scratches crossing different depth levels are sequentially segmented in three levels/steps in an immersing way. A number of parameters derived from this method were utilised to compare 3D interference measurements from the top dead centre, middle and bottom region of a liner run in a truck engine test whereas the three regions represent different wear regimes due to the different running conditions. The results show that: (i) the axial scratches are densest in the top dead centre and about the same size as the plateau grooves in all three regions, while in the bottom region there are only few scratches; (ii) the presence of plateau grooves in the top region clearly decreases, (iii) the deep groove interrupt and coverage are lowest in the top region, and (iv) the groove height and distance between grooves spread mostly.

  • 162.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Anderberg, Cecilia
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK). Volvo Cars Corp. Base Engine Department Gothenburg, Halmstad, Sweden.
    Ohlsson, Robert
    Volvo Power Train Corp, Volvo Group Gothenburg, Halmstad, Sweden.
    Rosén, Bengt-Göran
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Characterisation of Cylinder Liner Honing Textures for Production Control2013In: Characterisation of Areal Surface Texture / [ed] Richard Leech, Berlin: Springer Berlin/Heidelberg, 2013, p. 281-302Chapter in book (Refereed)
    Abstract [en]

    It is of common interest to reduce oil consumption and frictional losses in internal combustion engines, which are heavily influenced by the quality of the cylinder liner surface. The plateau cross-hatch topography of a cylinder liner consists of a system of grooves of different density, width and depth, some parts covered by folded metal, and some parts totally interrupted and unbalanced as a result of imperfection in the honing process. These grooves are critical for good liner function, and need to be quickly and objectively quantified for an efficient surface finish development. A suitable way to do this is to use 3D interference measurements and to combine profile and image analysis. Thus, the features/parameters, such as honing angle, balance of honing texture, groove interrupts, width, height, and distance between grooves, are successively quantified. Here, these parameters, along with areal surface texture parameters in the published ISO specification standard were used in two case studies. The first case study is on the effect of the folded metal on the surfaces of run truck liners and the second is an evaluation of the improvements of the surface quality introduced by the diamond honing in production of car liners. In addition, based on the significant parameters of the surface, a general characterisation tool for qualifying the surface quality and determination of the required number of measurements is presented. © 2013 Springer-Verlag Berlin Heidelberg. All rights are reserved.

  • 163.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Guilbert, Franck
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces. Ecole Nationale Supérieure d'Arts et Métiers, Centre Arts et Métiers ParisTech, Aix en Provence, France.
    Lundmark, Jonas
    Applied Nano Surfaces Sweden AB, Uppsala, Sweden.
    Mohlin, Johan
    Gnutti Carlo Sweden AB, Gothenburg, Sweden.
    Rosén, B.-G.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Optimization of the Triboconditioning Process on External Cylindrical Surfaces2015In: Proceedings of the 15th International Conference on Metrology and Properties of Engineering Surfaces, Raleigh, NC: American Society for Precision Engineering (ASPE) , 2015Conference paper (Refereed)
    Abstract [en]

    The use of tungsten disulfide in tribofilms on functional surfaces has been a proven way to reduce the frictional losses in rolling and sliding contacts, especially in lubricated contacts at boundary and mixed regime. A suitable and cost-effective process to deposit tungsten disulfide is by ANS Triboconditioning, the mechano-chemical surface finishing process for improving the tribological properties of mechanical components made of steel or cast iron. However, it is not known what are the optimal process parameters, speeds and pressures, to achieve an optimal surface treatment. In this paper, the modifications of the work-piece surfaces under Triboconditioning have been tracked to optimize the process parameters. To closely control the conditions, a commercial tribometer with a block-on-ring configuration was used. Cylindrical tungsten carbide samples (representing the tool) were rubbed against steel rings (representing the work-piece) under two different loads and speeds. The ring surfaces of two different finishes (ground and honed) were measured on the same place before and after treatment to track the surface modifications. At last, the treated rings were rubbed against a flat steel surface in start-stop sequences that resemble pin-roller operating conditions of a truck valve train and the friction behavior was screened. The results show a reduction of the core roughness of the ring surfaces with the lowest friction for the ground rings treated by low load and low speed.

  • 164.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Kofod, Guggi
    InMold Biosystems, Farum & Høje-Taastrup, Denmark.
    Rebeggiani, Sabina
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Rosén, Bengt-Göran
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Evaluation of Durability of SOG-layers on Steel Surfaces by Wear and Scratch Tests2014Conference paper (Refereed)
    Abstract [en]

    Steel moulds with high precision surfaces are being used in various branches. Process aspects, like tool life and tribological properties, as well as design issues are of great importance. This work summarises experimental studies performed to test durability properties of SOG (spin-on-glass)-layers on steel surfaces. This coating technique is based on a newly developed method for surface preparation of tools which has been demonstrated to be durable for more than 66.000 replications in injection moulding processes without loss of surface fidelity. The procedure allows surface roughness reduction from approximately 200 nm Ra down to some few nm for high gloss applications, as well as easy transfer of large-area functional nanostructures on complex 3D surfaces.

    Three different types of surfaces were investigated: SOG-layered metal surfaces with three different layer thicknesses, one ingot casted and one electro slag remelted material (with hardness level of 950 and 2500 MPa, respectively). The metal surfaces were ground and polished to mirrorlike finishes.

    Three circular samples of each type were rubbed against a hard steel ball of 6.35 mm radius on a commercial pin-on-disk tribometer. To resemble the molding process a sliding speed of 2 mm/s and a load of 8 N were chosen. The tests were performed with 5 minutes intervals until the first damage on the surface were observed. In parallel, scratch tests were performed in the same tribometer. The surfaces were measured in-situ by a portable microscope and a stylus, and afterwards by a white light interferometer and scanning electron microscope to evaluate the size of the wear/scratch traces.

    The surface type with the longest time to damage and/or smallest wear/scratch traces was considered to be the most durable one.

  • 165.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Lööf, Pär-Johan
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Dumbreville, Lucas
    Halmstad University, School of Business, Engineering and Science. École nationale d'ingénieurs de Saint-Étienne (ENISE), Saint-Étienne, France.
    Rosén, Bengt Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Nilsson, Per
    Volvo Group Trucks Technology, Gothenburg, Sweden.
    Functional Parameters Screening for Predicting Wear between Two Cylindrical Surfaces with Different Finishes2017In: Mets&Props 2017: 16th International Conference on Metrology and Properties of Engineering Surfaces: Conference abstracts, 2017, p. 75-76Conference paper (Refereed)
  • 166.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Lööf, Pär-Johan
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Rosén, Bengt Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Nilsson, Per
    Volvo Group Trucks Technology, Gothenburg, Sweden.
    Functional parameter screening for predicting durability of rolling sliding contacts with different surface finishes2018In: Surface Topography: Metrology and Properties, ISSN 2051-672X, Vol. 6, no 2, article id 024005Article in journal (Refereed)
    Abstract [en]

    The reliability and lifetime of machine elements such as gears and rolling bearings depend on their wear and fatigue resistance. In order to screen the wear and surface damage, three finishing processes: (i) brushing, (ii) manganese phosphating and (iii) shot peening were applied on three disc pairs and long-term tested on a twin-disc tribometer. In this paper, the elastic contact of the disc surfaces (measured after only few revolutions) was simulated and a number of functional and roughness parameters were correlated. The functional parameters consisted of subsurface stresses at different depths and a new parameter called 'pressure spikes' factor'. The new parameter is derived from the pressure distribution and takes into account the proximity and magnitude of the pressure spikes. Strong correlations were found among the pressure spikes' factor and surface peak/height parameters. The orthogonal shear stresses and Von Mises stresses at the shallowest depths under the surface have shown the highest correlations but no good correlations were found when the statistics of the whole stress fields was analyzed. The use of the new parameter offers a fast way to screen the durability of the contacting surfaces operating at similar conditions. © 2018 IOP Publishing Ltd.

  • 167.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Ohlsson, Robert
    Volvo Group Trucks Technology, Gothenburg, Sweden.
    Rosén, Bengt-Göran
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Effect of the measurement size on the robustness of the assessment of the features specific for cylinder liner surfaces2014In: Surface Topography: Metrology and Properties, ISSN 2051-672X, Vol. 2, no 1, article id 014013Article in journal (Refereed)
    Abstract [en]

    The quality of the cylinder liner surface is of great importance due to its impact on the fuel/oil consumption and emissions of the internal combustion engine. A good liner function depends on the size and distribution of the deep honing grooves and the amount of the cold work material (Blechmantel) left inside the grooves after finishing. A fast evaluation of these features requires optical three-dimensional measurements with a large area and good resolution, but many interferometers used today have limited resolution when measuring larger areas. To find out how the measurement size and resolution would affect the quantification and the variation of the parameters, two objectives, 2.5 ×  and 10 × , were used for measuring a cylinder liner from a truck engine. The Blechmantel was of special interest as it first comes into contact with piston/rings, detaches as particles and wears the running surfaces. The 2.5 ×  objective showed more robust assessment than the 10 ×  one, manifested by a lower coefficient of variation for the parameters describing the features: Blechmantel, groove width and height, groove balance and number of grooves. This means that fewer measurements are required if a 2.5 ×  objective is used in production and hence the time and cost of the liner would be decreased. © 2014 IOP Publishing Ltd.

  • 168.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Ohlsson, Robert
    Volvo Group Trucks Technology, Gothenburg, Sweden.
    Rosén, Bengt-Göran
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Effect of the Measurement Size on the Robustness of the Assessment of the Features Specific for Cylinder Liner Surfaces2013In: Metrology and Properties of Engineering Surfaces, 2013: Proceedings of the 14th International Conference on Metrology and Properties of Engineering Surfaces, 2013, p. 377-381Conference paper (Refereed)
    Abstract [en]

    The quality of the cylinder liner surface is of great importance due to the impact on the fuel/oil consumption and emissions of the internal combustion engines. A good liner function depends on the size and distribution of the deep honing grooves and amount of the cold work material (Blechmantel) left inside the grooves after finishing. A fast evaluation of these features requires optical 3D measurements with a larger area and good resolution, but the commercial interferometers used today are with limited resolution when measuring larger areas. To find out how the measurement size and resolution would affect the quantification and number of measurements needed for a robust assessment, two objectives, 2.5x and 10x, were used for measuring a cylinder liner from a truck engine. The Blechmantel was of a special interest as it first comes into a contact with piston/rings, detaches in particles and wears the running surfaces. The 2.5x objective showed more robust assessment than the 10x one manifested with lower number of measurements needed for the parameters describing the features: Blechmantel, groove width and height, groove balance and number of grooves.

  • 169.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Ohlsson, Robert
    Volvo Power Train Corp Sweden.
    Rosén, Stefan
    Toponova AB, Sweden.
    Rosén, B.-G.
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Characterisation of transparent deposits on cylinder liner surfaces of HDD truck engines2009Conference paper (Refereed)
  • 170.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Tomanik, Eduardo
    MAHLE Metal Leve, Jundiai, Sao Paulo, Brazil; University of Sao Paulo, Sao Paulo, Brazil.
    Grange, Simon
    Halmstad University, School of Business, Engineering and Science. École nationale d'ingénieurs de Saint-Étienne (ENISE), Saint-Étienne, France.
    Epinat, Flavien
    Halmstad University, School of Business, Engineering and Science. École nationale d'ingénieurs de Saint-Étienne (ENISE), Saint-Étienne, France.
    Novel Testing Methods for Screening the Tribological Performance of Ring-Liner Surfaces2017In: Mets&Props 2017: 16th International Conference on Metrology and Properties of Engineering Surfaces: Conference abstracts, 2017, p. 59-60Conference paper (Refereed)
  • 171.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Tomanik, Eduardo
    University of Sao Paulo, Sao Paulo, Brazil.
    Grange, Simon
    Halmstad University, School of Business, Engineering and Science. ENISE, St. Étienne, France.
    Epinat, Flavien
    Halmstad University, School of Business, Engineering and Science. ENISE, St. Étienne, France.
    Novel testing methods for screening the tribological performance of ring-liner surfaces2018In: Surface Topography: Metrology and Properties, E-ISSN 2051-672X, Vol. 6, no 3, article id 034017Article in journal (Refereed)
    Abstract [en]

    The piston system accounts for about the half of the frictional losses of internal combustion engines and requires special testing methods to understand and improve its function. The most common way to screen the surface performance is to rub ring/liner segments against each other in a reciprocating manner. However, short reciprocating tests have intrinsic low sliding speeds, unable to reach the mixed/hydrodynamic regimes found in the engine, especially at the mid-stroke. This paper presents a rotating test for the oil control ring, which has the largest frictional losses of all other rings. Both reciprocating and rotating tests were conducted using different in-house developed modules and fixtures. Twin land oil control rings against liners with two different finishes commonly used in heavy duty diesel truck engines were tested under similar loads and speeds as in a real engine. Engine oil 5W-30 and room temperature was used for all the tests. Sliding speed, load, friction force and electrical resistance were recorded during the tests. The results show a clear discrimination of the different liner finishes depending on the lubrication regime present.

  • 172.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Tomanik, Eduardo
    MAHLE Metal Leve, Jundiai, Sao Paulo, Brazil.
    Profito, Francisco
    University of Sao Paulo, Sao Paulo, Brazil.
    Influence of measurement and filtering type on friction predictions between cylinder liner and oil control ring2016In: Tribology International, ISSN 0301-679X, E-ISSN 1879-2464, Vol. 100, p. 7-17Article in journal (Refereed)
    Abstract [en]

    It is of a vital importance to reduce the frictional losses in the engines and hence the fuel/energy consumption. The major contributors to this are the oil control ring and cylinder liner interactions difficult to understand when comparing the experimental and theoretical results. The latter largely depend on the liner surface measurement and filtering type used in the simulations. Therefore, low-pass and high-pass filtrations were applied and the friction behaviors between the filtered liner surfaces and a perfectly flat ring surface were simulated for different engine speeds. The surfaces low-pass filtered by lower cutoffs showed higher friction, while the type of de-noising revealed about two and a half times higher friction. Stylus surfaces showed larger friction than the interference ones. © 2015 Elsevier Ltd. All rights reserved.

  • 173.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Tomanik, Eduardo
    Mahle Metal Leve, Jundiai - Sao Paulo, Brazil.
    Profito, Francisco
    University of Sao Paulo, Sao Paulo – SP, Brazil.
    Influence of Surface Waviness on Predictions of Friction between Cylinder Liner and Oil Control Ring2015In: Proceedings of the 42nd Leeds – Lyon Symposium on Tribology, September 7-9, 2015, Lyon, France, 2015Conference paper (Refereed)
    Abstract [en]

    It is of a vital importance for automotive industry to reduce the frictional losses in internal combustion engines and hence their fuel consumption and CO2 emissions. The major contributors to this are the oil control ring (OCR) and cylinder liner interactions. These interactions are of complex multi-physics and multi-scale nature and many attempts have been made to improve the modelling and understanding of the phenomena involved. Even though continuous improvements have been made (see for ex. [1-3]), the form, waviness and roughness variation of real engineering surfaces still cause a large scatter in the results. The most of the models include measured liner surfaces, which are then filtered to capture the micro-effects of the roughness scale. However, by doing this, the contact conditions change (asperity contact distributes more evenly, see Fig. 1) such that the part of the boundary friction reduces and the part of the hydrodynamic friction increases accordingly for a given engine speed. This study focuses on one of these multi-scale problems, namely on how the 3D measurement type/size and filtering affects the predictions of friction between cylinder liner and OCR of truck engines. Two types of 3D liner surface measurements were investigated: (i) interference (with an objective of 2.5x, size of 2.5x3.3mm) and (ii) 4x8mm stylus measurement. The form was removed by fitting and subtracting a 2nd order polynomial and the waviness was filtered out by using a robust Gaussian filter with three different cutoffs: 2.5mm, 0.8mm and 0.25mm. The friction behaviours (i.e. the Friction Mean Effective Pressure-FMEP) between the primary/ filtered liner surfaces and a perfectly flat ring surface were then simulated for different engine speeds. The relative errors of the OCR’s FMEPs with respect to the primary surface were evaluated and results discussed.

  • 174.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Yoann, Charon
    Perrier, Maxime
    Cabanettes, Frédéric
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Rosén, Bengt-Göran
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    A Sensitivity Study of the Tribotesting Setup to Rate Different Liner Surfaces2012In: 15th Nordic Symposium on Tribology: NordTrib 2012, Trondheim, 2012Conference paper (Refereed)
  • 175.
    Dincay, Berkan
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    GPS/Optical Encoder Based Navigation Methods for dsPIC Microcontroled Mobile Vehicle2010Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Optical encoders are being widely suggested for precise mobile navigation. Combining such sensor information with Global Positioning System (GPS) is a practical solution for reducing the accumulated errors from encoders and moving the navigational base into global coordinates with high accuracy.

    This thesis presents integration methods of GPS and optical encoders for a mobile vehicle that is controlled by microcontroller. The system analyzed includes a commercial GPS receiver, dsPIC microcontroller and mobile vehicle with optical encoders. Extended kalman filtering (EKF), real time curve matching, GPS filtering methods are compared and contrasted which are used for integrating sensors data. Moreover, computer interface, encoder interface and motor control module of dsPIC microprocessor have been used and explained.

    Navigation quality on low speeds highly depends greatly upon the processing of GPS data. Integration of sensor data is simulated for both EKF and real time curve matching technique and different behaviors are observed. Both methods have significantly improved the accuracy of the navigation. However, EKF has more advantages on solving the localization problem where it is also dealing with the uncertainties of the systems.

  • 176. Duncalf, Alexandra
    et al.
    Persson, Katarina
    Chamma, Alexander
    ConneXion2015Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
  • 177.
    Dunert, Sofie
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Kristoffersson, David
    Halmstad University, School of Business and Engineering (SET).
    Zilent Ocean: EL-KONVERTERING AV INOMBORDSMOTORER TILL SEGELBÅTAR2009Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Through extensive research it has shown that today’s sail boat owners are very frustrated concerning the limited choice of engine alternatives offered by today’s market. Besides rising fuel-costs, environmental awareness is very important in today’s society. Hence it is vital to find alternative environmental-friendly motors and replace combustion-engines.

     

    Zilent Ocean is an extensive project within Development engineering program at Halmstad University. The Project aims at minimizing environmental impact on our seas through limiting the usage of combustion-engines in sail boats. Zilent Ocean’s major target is the development of a customer-oriented company offering electric conversion kits of combustion-engines to sail boats at very competitive market prices.

     

    The Project was carried out by converting the combustion-engine in a MAXI 77 sailing boat (7.7m length, 5 beds). The current diesel-engine installed in the boat was replaced with a new DC electrical engine together with the appropriate controller unit.

     

    The finished sail boat prototype will be evaluated under the summer of 2009. The sail boat contains unique solutions enabling a more cost-efficient system in comparison with today’s combustion-engines. The aim is to provide a complete electric conversion kit at a lower price than a new combustion-engine. Together with lower investment costs, minimal maintenance and running costs, electrical conversion from Zilent Ocean is bound to be the future, and the natural decision for many sailors in Scandinavia.

  • 178.
    Eckerljung, Daniel
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Hugoh, Jakob
    Halmstad University, School of Business and Engineering (SET).
    Framtagande av ställbar krok för hängränna2013Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    The purpose of this project was to design an adjustable gutter bracket for Lindab Profil AB. Lindab currently manufacture a gutter bracket that is adjustable in angle, however, this model has some drawbacks.  One of it´s shortcomings is that it is somewhat difficult for the customer to mount.  Another problem with Lindab’s current model is that the design makes manufacturing unnecessarily complex. The new gutter bracket, that we have constructed, does not have these problems. It is adjustable for different roof pitches. It is easy to mount to the fascia board and the manufacturing process has been simplified as well.

    In the project we have used a design methodology developed by Fredy Olsson.  In addition to designing the product we have performed FEM analysis, to ensure that it will endure  loads and stress.  We have used the CAD software Catia v5 for this, and for the 3d models. Drawings are attached to  the document.

  • 179.
    Edman, Fredrik
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Jansson, Jonathan
    Halmstad University, School of Business, Engineering and Science.
    Aerodynamiskt fotstöd: Utveckling av individanpassat fotstöd för paracyklist2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has focused on aerodynamics in hand cycling. Hand cycles are used by people with disabilities, paralysis or amputation of a lower limb.

    The idea for the project was initiated by a para-cyclist who suspected that his feet were causing an unnecessarily large air resistance when racing. The aim of this project was therefore to investigate this suspicion. If the excessive air resistance was confirmed, a new footrest would be developed to reduce it. The project was conducted in collaboration with the orthopedic clinic Team Olmed who had previously had contact with the user.

    Simulations on the feet were carried out in FloEFD to investigate the air resistance caused by the feet. Any excessive air resistance could then be confirmed and the development of a new footrest that would reduce drag could begin. Through literature studies regarding aerodynamics and analogies, brainstorming and brainwriting and with help from experts different concepts were generated. The concept of a streamlined footrest served as a basis to reduce the air resistance. Two of the concepts were modeled with a rounded shape that gently breaks the air and forms a streamline along the body. New simulations were conducted and later compared with the old footrest and the new streamline characteristics could then be confirmed.

    The result of the post simulations cannot be definitively quantified, but they indicate that air resistance is reduced by about 0,3 N for the two new footrests. This represents an improvement of 12-15 seconds for the cyclist on a 20 km race, which could be crucial in future competitions. The concept that provided the lowest air resistance was also developed as a prototype. The prototype was tested on the user's bicycle and feet with a satisfactory result.

    The project shows that it is relevant to develop more aerodynamic footrests in the sport hand- cycling. The time saved with the footrest developed in this project had meant the difference between victory and a fourth place at the Paralympics in 2008.

  • 180.
    Edqvist, Ola
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Abbas, Rand
    Halmstad University, School of Business, Engineering and Science.
    Konstruktion av justerbart sågstöd2016Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
  • 181. Ekelund, Anna
    et al.
    Standar, Eric
    ecGo - Charge, Pay & Go!2015Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
  • 182. Ekelund, Johan
    et al.
    Nilsson, Martin
    Anslagstavlan VERA2014Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
  • 183. Ekeroth, Emil
    et al.
    Hultin, Joel
    ClickitUp2014Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
  • 184.
    Ekeroth, Tobias
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Forssmark, Linda
    Halmstad University, School of Business and Engineering (SET).
    TELF: Vänder rätt i nöd2012Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Abstract

    In year 2011 95 people drowned, that is an increase of 16 persons from 2010. Drowning in connection with boats is the most common cause and in year 2010 29 persons died in connection with boats.

    When rescue crew arrive to an scene of accident with a capsized boat they must improvise the rescue. It is very important that they turn the capsized boat to the right keel in order to secure that no one is stuck under the boat. The rescue crew cannot leave an abandoned boat out on the sea because it can cause new accidents and to tow a boat on the wrong keel is very difficult.

    TELF is a tool that facilitate the rescue with capsized boats. With TELF the rescue crew do not have to improvise the rescue work, they know directly what to do. TELF throws over the capsized boat and with the rescue boat as a counterforce they can drag the boat to its right keel again.

    TELF is designed to a turn capsized boats to its right keel, but it can also be used to drag a burning boat out from the harbour to avoid other boats from catching the fire. With TELF the rescue crew can feel secure, they do not have to improvise the rescue work, now they know directly what to do. 

  • 185.
    Ekström, Johan
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Mickelsson, Rikard
    Halmstad University, School of Business and Engineering (SET).
    Auto Deco Primer Valve2012Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Auto Deco Primer Valve är ett projekt som har resulterat i ett förenklat startsystem för tvåtaktsmotorer.

    Att starta en tvåtakts motor med dragsnöre är både tidskrävande och jobbigt, därför vill projektgruppen ge samhället en lösning på problemet.

    Genom ett befintligt koncept har syftet varit att fullborda detta system genom en ny innovativ lösning i form av en multifunktionel ventillösning.

     

    Ventilen och dess ingående system är tänkt att ersätta två funktioner som återfinns på de flesta tvåtaktsmotorer idag: Dekompressionsventil och Chokereglage

     

    Vår nya ventil gör att det tidigare manuella systemet automatiskt, och tar på så sätt bort de steg som måste utföras innan motorn startas.

     

    Det nya systemet som förverkligas i ”Auto Deco Primer Valve” kommer att medföra många fördelar som beskrivs utförligare längre fram i rapporten.

     

    Målet vid projektets slut har varit att ta fram en fungerande prototyp vilket projektgruppen har åstadkommit.

    Arbetet har inneburit en stor del av kreativt tänkande, för att kunna kombinera vetenskap om bland annat pneumatik med ett mekaniskt system.

     

    För att bygga ett hållbart system som klarar marknadens tuffa krav och samtidigt inte är beroende av elektricitet så har stor del av arbetet bestått av att utveckla, beräkna, dimensionera, samt förenklat systemets olika delar och sedan modellera detta i Catia V5 R20.

     

    Projektet har resulterat i en funktionsprototyp med fullständigt CAD-underlag som Husqvarna AB kommer att använda till att vidareutveckla systemet.  

    Med detta arbete vill vi ge samhället och framförallt skogsbranschen ett tillförlitligare hjälpmedel, genom en ny innovativ lösning, som gör att ett motorsystem för tvåtaktsmotorer blir mer driftsäkert, lättare att använda och snabbare att starta.

  • 186.
    Elghoul, Zoelfikar
    Halmstad University, School of Business and Engineering (SET).
    Manganese phosphate coating mini-line lab2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The following report is conducted in collaboration with the University of Halmstad. As the development of today's vehicles demands environmentalregulations require reduced emissions of CO2, performance, economy and safety, Lighter and efficient vehicles in transmission, this intensive development coupledwith re-optimization of the conflicting demands driveability, durability,efficiency and noise comfort. During the past 10 year the design margins hasbeen reduced. This means that the former research experience must be renewedfor development continues. As a part of the research conducted at HalmstadUniversity is an interest in being able to prepare these surfaces in different ways,in a lab environment. In this thesis, two processes in question, manganesephosphate and coating treatment.

    The purpose of this project is to construct a mini lab which will achieve theprocess of the surface treatment of machine element components in a laboratoryenvironment.

    The purpose of this project is to design and control the process which willconfigure all the details and specification required to achieve stagesof phosphate process as well the properties of every details in the chain ofimmersion and safety environment during the process stages, the task alsoincluding Risk analysis.

    The method that used was the same that was used by us during earlier courses inconstruction method written by Fredy Olsson, method principle /primary andmanufacturing. The development of the design has been done using brainstorming. The basic idea is a common idea where this since developed into aprototype.

  • 187.
    Elghoul, zoelfikar
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    John, Shobin
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Surface Topographical  Analysis Of Cutting Inserts2016Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    The following report conducted with collaboration of the University of Halmstad and ABSandvik Coromant.The focus of the project is characterizing the surface topography of different surface treatmentvariants before and after chemical vapor deposition (CVD).As a part of improving the knowledge about the surface area characterization and accomplisha better knowledge and understanding about surfaces and its relation to wear of uncoatedWC/Co cutting tools The project initiated in February 2016 and end date was set to May2016.The methodology used in this thesis based on the statistical analysis of surface topographicalmeasurements obtained from interferometer and SEM by using Digital-Surf-MountainsMapsoftware.The finding from this thesis showed that Mean and Standard deviation method, Spearman’scorrelation analysis and Standard deviation error bar followed by ANOVA and T-test areeffective and useful when comparing between different variants.The thesis resulted in a measurement approach for characterizing different surfacetopographies using interferometer and SEM together with statistical analysis.Keywords: 3D-Surfaces Texture, CVD coating inserts, Interferometer, Spearman’s correlation andANOVA & T-test.

  • 188.
    El-Ghoul, Zoel-Fikar
    et al.
    Halmstad University, School of Business, Engineering and Science.
    John, Shobin
    Halmstad University, School of Business, Engineering and Science.
    Dimkovski, Zlate
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Lööf, Pär-Johan
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Lundmark, Jonas
    Applied Nano Surfaces AB, Uppsala, Sweden.
    Mohlin, Johan
    Gnutti Carlo Sweden AB, Gothenburg, Sweden.
    Wear Analysis of Pin and Roller Surfaces2017In: Mets&Props 2017: 16th International Conference on Metrology and Properties of Engineering Surfaces: Conference abstracts, 2017, p. 190-192Conference paper (Refereed)
  • 189.
    Eliasson, Algot
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Smith, Adam
    Halmstad University, School of Business, Engineering and Science.
    Utveckling av ID-scanner2015Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
  • 190.
    Elofsson, Jesper
    Halmstad University, School of Business and Engineering (SET).
    Förbättring av dockning mellan lastvagn och autoklav2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    At present Getinge can offer a new generation of trolleys that they produced in 2011. The trolley used to Getinge various autoclaves and has the primary task to help the user/sterilization personnel to transport shelves or baskets, with or without cargo, from a packing table to the autoclave. The purpose of this thesis has been to develop a primary solution how the docking process between Getinge trolleys and autoclaves can be improved. The work has in most part followed Fredy Olsson principle and primary construction method. The work has included product research, study visit and development of a requirements specification, to satisfy Getinge, their clients and circumvention products requirements. Using this information, it was taken up various product proposals were screened out by testing prototype and study of Cad-model, until only one product suggestions residue. The product proposal led to a primary solution that was designed and calculated in CATIA V5 and a simple prototype of the primary solution.

    The work resulted in a new loading area to Getinge trolleys. The loading area will help users on sterilization stations through an increased precision tolerance, which facilitate the docking process between the trolley and autoclave.

  • 191.
    Elwing, Johan
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Krantz, Jonathan
    Halmstad University, School of Business, Engineering and Science.
    Design och analysering av bränsletank2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta arbete innefattar en allmän jämförande studie kring materialval för personbilarsbränsletankar, en framtagning av ett tankkoncept samt en analys av kravlistor.Materialen som studeras är plast och stål, närmare sagt sexlagrig HDP E (Hög-densitetpolyeten) plast med EVOH (Etylenvinylalkohol) lager och en stålplåt vars egenskaperhar tagit utgångspunkt i ett genomsnittligt utförande som speglar en generell bild avvanligt använda material. Arbetet resulterar i en presentation av ett färdigttankkoncept som utnyttjar speciella möjligheter vilka uppstår vid plåtanvändningtillsammans med för- och nackdelar kring de olika materialvalen. Även en bilaga medförslag på kravändringar tillkommer arbetet.

  • 192.
    Emma, Reinholdsson
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Hannah, Carlbom
    Halmstad University, School of Business, Engineering and Science.
    Skyltdockor på moderna människors vis: Ett innovativt utvecklingsarbete där digital teknologi har använts för att skapa mjuka värden så som inkludering, jämlikhet och välmående.2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 193.
    Engdahl, Annelie
    Halmstad University, School of Business, Engineering and Science.
    How grid connected solar cells impact on the low voltage grid of Duckarp2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To limit the ongoing climate change and to meet the UN target for an increased temperature of maximum 2 degrees, governments worldwide strive for sustainable and fossil free power generation. Hence, Photovoltaic Solar Cells (PVs) are of great interest. The potential from sun is infinite; the annual solar radiation corresponds to 6.000 times the human energy demand (IEA, 2011).

    In Sweden, the power generation from sun is 0.6 ‰ (Swedenergy, 2016). It is a very small, but strongly growing, share. In the municipality of Kristianstad, south of Sweden, the vision of power generation from sun is clear: by 2040, 5 % of the electricity consumption in the area is to come from PVs (Kristianstad kommun, 2016). Along with an increased interest from subscribers, more grid connected PVs are to be expected.

    An increased share of grid-connected PVs, influences the power grid. The power quality must comply with legal requirements and maintain a certain voltage. This might be a problem in rural power grids where the distances are far; the grid is getting weaker and the voltage deviation grows. Never the less, the law requires the concession holder to compensate the subscriber in relation to the decreased losses in the grid. With power generation closer to the subscriber, the distances are shorter and the grid losses is decreased.

    Mellersta Skånes Kraft (MSK) is a power distribution company located in Scania, south of Sweden. In the feeding 6 kV grid, a major part of the conductors are over-head lines, meaning a lot of interruptions caused by stormy weather and fallen trees. Hence, MSK is planning for isolated conductors to decrease the number of interruptions. 

    At present, MSK have a few, sporadically placed, grid connected PVs and the power generation of today, regarding power quality, is not a problem. However, MSK sees an increased interest in PVs and more power generation the next few years are to be expected. The question is, how several grid-connected PVs will impact the power grid.

    In this dissertation, the rural low voltage grid of Duckarp, Kristianstad municipality, has been studied. The grid is connected to the very last transformer in a radial grid. Two cases have been modulated: one with existing PVs of today, and one with PVs at all subscribers connected to the transformer T-640, Duckarp. As the feeding 6 kV grid is to be rebuilt, the study included the choice of cable cross section area in the 6 kV grid as well. The study included grid strength, voltage deviation, load in cables and transformer, and grid losses including compensation to subscriber.  

    The study shows, that with present PVs and with the condition that a tap changing transformer is used, the grid is strong and capable of keeping the voltage required. Due to voltage deviation, more grid connected PVs make the grid weaker and require higher cable cross section areas on the feeding 6 kV grid. The load is not a problem, but still there is a risk of a high proportion of harmonics in the neutral and in the transformer. This, due to the low voltage grid being located in the weakest part of the grid. The reduced losses, due to local power generation, corresponds to a compensation to subscriber of 0.02 SEK/kWh.

    Building strong power grids is expensive and alternative solutions, so-called smart grids, are of interest; Line Voltage Regulator (LVR), reactive power generation in the inverter, battery storage, or load regulations to mention some. But when there is an ongoing reconstruction of the grid, as in the case studied, it is appropriate to build a strong power grid to meet a future expansion of grid-connected PVs.

  • 194.
    Ericsson, Alexander
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Gutestam, Elliot
    Halmstad University, School of Business, Engineering and Science.
    Simuleringsbaserad optimering av produktionsflöde2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis project has been carried out in collaboration with Skövde University with the purpose of demonstrating, through simulation and optimization, production parameters impact on a system’s overall performance. The aim of the thesis was to create a simulation model from production data that accurately reflect a real-life system and could be used for optimization. 

    A method of simulation model construction was developed through a combination of theories from Banks (1998) and Lundgren et al. (2010), which were practiced by building a model based on data from a real production facility. The research questions and requirements were developed with the client regarding the performance of the model and were evaluated before optimization parameters for sequence, batch-size and Buffer- and Store capacity were defined and established. The result that the optimization generated was analyzed, evaluated, and compared to results from own experiments to ensure its credibility. 

    The project has contributed to a new view of the production flow that was simulated and showed that the most obvious parameters are not always the ones that affect the process the most. The results show an improvement of 64% in total capacity and over 24 hours shorter lead time. The report highlights a company’s benefits with using simulation in its work with production development. Especially to minimize the risk of wasting resources to improvements with lower potential than others. 

    The simulation model developed in the project will serve as basis for further work in understanding and investigating productions technical parameters and their correlations with each other.

  • 195.
    Ericsson, Karin
    et al.
    Environmental and Energy Systems Studies, Department of Technology and Society, Lund University, Lund, Sweden.
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    The introduction and expansion of biomass use in Swedish district heating systems2016In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 94, p. 57-65Article in journal (Refereed)
    Abstract [en]

    District heating satisfies about 60% of the heat demand in Swedish buildings. Today, more than two thirds of the heat supply to the district heating systems is based on biomass and waste, and biomass alone accounts for about half of the heat supply. The purpose of this paper is to present the Swedish experiences of introducing and expanding the use of biomass in the district heating systems and to identify the main drivers behind this development. Our five research questions and the corresponding conclusions consider the driving forces from energy policy tools and local initiatives, the biomass prices, the established infrastructures in forestry and district heating, the technology paths for biomass conversion, and finally the future challenge of competing uses of biomass. © 2016 The Authors

  • 196.
    Eriksson, Anna
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Carlfjord, Salli
    Halmstad University, School of Business, Engineering and Science.
    Utveckling av metod för benkvalitetsmätning2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Dental implant surgery is performed daily to replace single teeth and entire tooth rows. Implant selection is based on the bone quality of the cortical and trabecular bone in the jaw bone. Usually, the surgeon assesses the bone quality subjectively during drilling in the jaw bone. The aim of this project has been to increase the ability to give the surgeon a direct feedback on the bone quality during threading in a pre-drilled hole, so the right type of dental implant can be chosen. The idea of the project comes from Lennart Carlsson at TL Medical AB, who has developed a custom-made tap that is used together with a drilling machine that measures the torque during threading. Carlsson has done measurements in polyurethane foam with densities of 1050, 500 and 300 kg/m3.

     

    Through regression analyzes in MATLAB on Carlsson's measurements, a linear relationship between torque and number of turns the tap has threaded the material was found. The mean slope value of thirteen measurements/density ± SD was 8.0 ± 0.5 Ncm for density 1050 kg / m3. For density 500 kg / m3 the mean was 1.1 ± 0.2 Ncm and for density 300 kg / m3, the mean was 0.3 ± 0.1 Ncm. The relationship varied depending on which density that was investigated but the lowest achieved R2 value was 0.7. The project has resulted in a table of bone quality and maximum torque. The various ranges for maximum torques were divided into bone qualities as follows: Quality 1 ≥ 26 Ncm, 20 < Quality 2 < 26 Ncm, 12 < Quality 3 ≤ 20 Ncm and Quality 4 ≤ 12 Ncm. Own measurements in ribs from calf were performed to compare the results from the table with the reality. Five measurements out of 11 were in accordance with the table regarding bone quality while the other measurements were either one classification higher or one classification lower than the table.

     

    The most important findings are the relationship between the torque size during threading and the different material densities and that the custom-made tap produces a linearly increasing torque for each cut threading in the material. The project group realizes that more tests would have to be done, especially on human tissue, to validate the developed bone quality scale.

  • 197.
    Eriksson, Carl-Johan
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Erlingsson, Jonas
    Halmstad University, School of Business, Engineering and Science.
    FRP i brokonstruktion: -varför används FRP inte i Sverige2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    FRP stands for Fiber Reinforced Polymer. FRP materials have yet to be introduced inbridge construction in Sweden. Composite materials can through combined componentsand manufacturing processes be tailored to fit advanced bridge designs. FRP materials arestrong, durable and of low weight. FRP materials give the superstructure reduced weightand are therefore a suitable alternative for industrial prefabrication. This report shows thatFRP materials are possible to use in bridge construction. With the introduction of a specificEurocode we are confident that FRP materials will become a competitive alternative inbridge construction in Sweden in the future.

  • 198.
    Eriksson, Filip
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Gustafsson, Albert
    Halmstad University, School of Business and Engineering (SET).
    EasyMill - En kompakt CNC-fräs för träskivor2013Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    This

    report

    is

    a

    thesis

    for

    the

    Technicians

    in

    Computer

    Aided

    Design

    program

    at

    Halmstad

    University.

    The

    group

    has

    developed

    a

    milling

    machine

    mainly

    used

    for

    fiber

    boards,

    on

    behalf

    of

    Johan

    Wretborn.

  • 199.
    Eriksson, Fredrik
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Karlsson, Martin
    Halmstad University, School of Business and Engineering (SET).
    Framås, Kjell Ivar
    Halmstad University, School of Business and Engineering (SET).
    Sekundärnät för lågtempererad fjärrvärme2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Lower energy use in buildings is a result of increasingly stringent energy requirements across Europe. When conventional district heating technology is used in areas with low energy consumption heatlosses do not fall even though the amount of energy delivered is reduced. This reduces income for thedistrict heating company. To maintain their economic viability the district heating companies’ majorchallenge is to implement new solutions that minimize heat loss. This report aims to provide the district heating company Eidsiva Bioenergi AS an example of thepossibilities and limitations of a secondary low temperature district heating system. Focus areas arepast and present limitations of plastic pipes and on what temperatures may be used when taking intoconsideration the potential for growth of Legionella bacteria in hot water systems.The report's goal is to present a theoretical design of a low temperature secondary network for districtheating located in Lillehammer, Norway. The report is written in collaboration with the Norwegiancompany Eidsiva Bioenergi AS.The given solution consists in a secondary low temperature district heating system built with plasticpipes supplying four apartment buildings of a total of 360 student apartments. The network shouldmaintain a supply temperature of 60 °C and a return temperature of 30 °C.A secondary network means lower pressure and temperature levels, making it possible to use plasticpipes. Plastic pipes have an advantage regarding installation as they do not require welding and can besupplied in lengths of 50,100 or 200 meters which can speed up trenching work. The authors are of the opinion that the present plastic piping technology have an adequate technicaldurability and does no longer cause problems with oxygen diffusion if installation is done correctly. Although it was possible to design a secondary low temperature district heating network with lowerheat losses, it was not the most profitable in this case even though heat losses are lower than forconventional technology. Secondary low temperature district heating network with plastic pipes aremore competitive in areas with lower energy demands. We recommend that Eidsiva Bioenergi AS to gain knowledge from this report and look foropportunities to implement the solution in areas where conventional technology is less competitive,such as in new housing developments and more heat sparse areas. The technology can also have great advantages in areas with difficult topography or where longer periods of open trenches are not wanted. In all these cases the fast and flexible installation of plastic pipes can give great financial savings.

  • 200.
    Eriksson, Jacob
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Edelönn, Erik
    Halmstad University, School of Business, Engineering and Science.
    Vision 2045: Ett förnyart Halland2019Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis
    Abstract [en]

    Since the resolution made in Paris during the COP21 conference in 2015, governments have been hard at work implementing new regulations accordingly. Regional authorities in Sweden has been given the task of managing and constructing strategies in the field of energy and environmental policies. This thesis aims at analysing the potential for the county of Halland to become a sustainable and renewable region in the longer term as well as to achieve the objectives of the Swedish government. It does so in cooperation with the representing regional authority, The County Administration Board in Halland, and their work form the basis of method for this paper.

     

    The purpose of this paper has been to indicate, demonstrate and motivate a sustainable change in Halland and to describe what technical possibilities are available of implementation as of today.

     

    Six main chapters constitutes the report and are structured in a way to cover contemporary theory, future opportunities and the author’s assumptions, opinions and suggestions of measures. The technical background and methodology in this paper has mostly consisted of studies of literature from sources within energy technology such as relevant authors, companies, authorities and research institutions.

     

    The results show that by the year 2045, a massive expansion of renewable energy is both theoretically and practically feasible, whilst levels of greenhouse gas emissions can be reduced by more at least two thirds compared to the levels of 2016.

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