Stålindustrin genererar en stor mängd CO2 utsläpp under materialproduktion. På grund av detta är det viktigt att optimera användningen av materialet så att mer utsläpp än nödvändigt ej genereras. Utöver onödiga utsläpp kan en materialbesparing även leda tilllägre kostnader i produktionen för företagen. Denna studie avser att kontrollera just detta genom att utföra optimeringsförsök på en ställning från företaget Bernoulli System AB. Ställningen var ursprungligen tillverkad för en av deras större vattenfilter, men används även till övriga filterstorlekar. Hypotesen som bildats är att ställningen bör vara överdimensionerad för deras mindre filter. De poängterar att benen i ställningen anses som mest intressanta vid en analys. Om det är möjligt skulle de även gärna använda sig av kommersiella plåtprofiler i stället för den nuvarande bockade plåten. Studien tar sig an att analysera den nuvarande konstruktionen för att besvara hypotesen ställd av företaget. Utöver detta så kontrolleras även möjligheterna att använda sig av kommersiella profiler för benen. Genom denna studie är förhoppningen att resultatet ska påvisa att även mindre konstruktioner kan generera stora procentuella besparingar vid optimering. I studien används modelleringsprogrammet Creo för att simulera en förenklad modell av den nuvarande ställningen som utgångsläge. Flertalet olika kommersiella profiler analyseras för ställningen för att uppnå en optimal optimering. Vissa förenklingar och avgränsningar har utförts i samråd med företaget för att möjliggöra studien. För att säkerställa att resultaten från simuleringarna i Creo är korrekta uppförs en analytisk modell i Matlab. Genom tilläggsprogrammet CALFEM beräknas modellens reaktionskrafter, som sedan räknas om till effektivspänningar med handberäkningar. Vid jämförelse mellan de båda resultaten skapas en form av valideringsmetod för studien. Valet av kommersiell profil som studerades blev UPE-profiler då de ansågs som det mest lämpade alternativet för konstruktionen. När fortsatt optimering ej kunde utföras längre sammanställdes resultaten för att kontrollera den möjliga besparingen. Studien stödjer företagets hypotes, benen i ställningen är överdimensionerade för deras mindre filter. Det är möjligt att optimera benen i konstruktionen och ersätta den bockadeplåten mot UPE-profiler. Enligt studiens analys kan en UPE-80 profil användas samt att både mittstång och stödplåt kan tas bort från ställningen. Anledningen till detta är att dessa delar är underdimensionerade i den optimerade konstruktionen. I dessa delar genereras en effektivspänning som överstiger det maximalt tillåtna värdet satt avföretaget på 96 MPa. Vid simulering av den optimerade konstruktionen i Creo uppnås en maximal effektivspänning till 89 MPa. Studiens slutsats blir därmed att en UPE-80 profil kan användas som ben för ställningen. Total besparing efter optimering av benen uppgår till ca 52 %. / The steel industry generates a large amount of CO2 emissions during material production. Because of this, it is important to optimize the use of the material so that unnecessary emissions can be avoided. Apart from the CO2 emission and material reduction, optimization can result in less costs in production for the company. This study intends to verify this by performing an optimization of a support used by the company Bernoulli System AB. The support was originally designed for one of their larger water filters, but is used for various filter sizes. The hypothesis formed by the company is that the support is oversized for their smaller filters. They specify that the legs are particularly interesting to analyze for the optimization. If possible, they would also prefer to use commercial metal profiles instead of the bent sheet metal used today. The study undertakes to analyze their current construction to answer the hypothesis posed by the company. In addition to this, the study will check the possibilities of using commercial material for the legs. Through this study the hope is that the result will show that even smaller constructions can genereate large percentage savings through optimization. To perform the study the modeling program Creo is used to simulate a simplified model of the current support. To achieve an optimal optimization for the support various simulations are performed with different profiles for the legs. Some simplifications and boundaries for the study have been made in consultation with the company to be able to perform the study. To ensure that the model in Creo works and gives correct results from the simulation, an analytical model is built in Matlab. Through the additional program CALFEM the model’s reaction forces are obtained, which can then be used in hand calculations to check the effective stress. By comparing the results from both methods a validation method is established. The choice of commercial profiles to test for the support became UPE-profiles since they seemed the most fitting as a substitute. When further optimization wasn’t possible the results were compiled to check the possible savings after the optimization. The study confirms the company’s hypothesis, the legs are oversized for their smaller water filters. It is possible to optimize the legs in the construction and replace the bent sheet metal with UPE-profiles. According to the study’s analysis a UPE-80 profile canbe used for the legs, and both the support plate and middle bars can be removed in the construction. The reason for the removal of these parts is because they are undersized for the optimized construction. This led to the parts generating a higher effective stress than allowed of 96 MPa. With the optimized construction simulated in Creo, a maximum effective stress of 89 MPa is achieved. The study therefore concludes that a UPE-80 profile can be used as the legs for the support. The total savings of the legs by performing the optimization is approximately 52 %.

Electrical machines form part of our everyday life at home and in industry plants. Currently induction machines are the backbone of the industry machine installation as these are robust, reliable and have relatively high efficiency. However as the price of energy increases and stricter efficiency regulations are put into place there is a need for more efficient electrical machines. The majority of induction machines on Sasol's plants are between 2.2 kW and 22 kW. Of these, 95% machines are connected to pump loads and 2% to fan loads. Thus the majority of the machines operate at a constant speed. Rather than try to improve an induction machine, this project proposes the design for a more efficient LS PMSM that can also be used in the same applications as mentioned above. Although LS PMSMs aren’t a new concept, the demand and industry interest in this technology has increased in recent years. Since 2000 the number of research publications with regards to this machine has increased significantly. The goal of this project is to gain a better understanding of these machines by designing a prototype. The design entitles the stator and rotor. As Sasol provided the funding for the project it was decided to design a three phase, 7.5 kW 525V, four-pole machine. During the design phase several design techniques done by other researchers were incorporated into the prototypes. The design is done with the aid of two FEM software packages namely FEMM and ANSYS Maxwell® and verified against calculated values. The final prototype is tested and compared to the predicted values determined during the design. An industry available LS PMSM from Weg, the WQuattro is also used to compare the results of the prototype. The prototype machine’s no-load, full load and locked rotor behaviour is tested as well as the back-emf waveform. From the results gained the machine is validated. The machine did not perform as predicted and further investigation into the reason is needed. Due to the incorrect wiring of the stator and some other rotor manufacturing issues the prototype cannot be fully validated. However it was found that several of the designed values correlated to the measured values. Further investigation into the under performances as well as more relevant testing and practical manufacturing method is needed. / MIng (Electrical and Electronic Engineering), North-West University, Potchefstroom Campus, 2014

Electrical machines form part of our everyday life at home and in industry plants. Currently induction machines are the backbone of the industry machine installation as these are robust, reliable and have relatively high efficiency. However as the price of energy increases and stricter efficiency regulations are put into place there is a need for more efficient electrical machines. The majority of induction machines on Sasol's plants are between 2.2 kW and 22 kW. Of these, 95% machines are connected to pump loads and 2% to fan loads. Thus the majority of the machines operate at a constant speed. Rather than try to improve an induction machine, this project proposes the design for a more efficient LS PMSM that can also be used in the same applications as mentioned above. Although LS PMSMs aren’t a new concept, the demand and industry interest in this technology has increased in recent years. Since 2000 the number of research publications with regards to this machine has increased significantly. The goal of this project is to gain a better understanding of these machines by designing a prototype. The design entitles the stator and rotor. As Sasol provided the funding for the project it was decided to design a three phase, 7.5 kW 525V, four-pole machine. During the design phase several design techniques done by other researchers were incorporated into the prototypes. The design is done with the aid of two FEM software packages namely FEMM and ANSYS Maxwell® and verified against calculated values. The final prototype is tested and compared to the predicted values determined during the design. An industry available LS PMSM from Weg, the WQuattro is also used to compare the results of the prototype. The prototype machine’s no-load, full load and locked rotor behaviour is tested as well as the back-emf waveform. From the results gained the machine is validated. The machine did not perform as predicted and further investigation into the reason is needed. Due to the incorrect wiring of the stator and some other rotor manufacturing issues the prototype cannot be fully validated. However it was found that several of the designed values correlated to the measured values. Further investigation into the under performances as well as more relevant testing and practical manufacturing method is needed. / MIng (Electrical and Electronic Engineering), North-West University, Potchefstroom Campus, 2014

Studien handlar om hur en butiksmiljö där alla fem sinnena är stimulerade påverkar konsumenternas shoppingupplevelse och om hur det kan påverka avslut till köp. Hypotesen är att besökaren kommer att ha en bättre shoppingupplevelse i den stimulerande miljön samt att de kunder som handlar gör fler avslut till köp. Studien bygger på ett experiment i en butik där alla sinnen utom synen tillförs eftersom det redan är stimulerat i butiksmiljön. Vi har valt att dela upp besökare och kunder i butiken i två olika grupper, där ena gruppen vet om det pågående experimentet och den andra gruppen vet inget. Dessa grupper ska jämföras för att visa hur de upplevde den nya miljön i butiken och om det finns skillnader mellan resultaten i respektive grupp. Vår studie visar inga resultat som stärker vår hypotes.

Introduction One of the products made by SAAB Avionics Systems in Jönköping was in need of a better cooling solution. The product, a Head-Up Display, holds a LED that was overheating when run at desired input power. The purpose of this thesis was to identify the design weaknesses in the current solution regarding heat dissipation and produce new design proposals that fulfill the requirements. The parts analyzed consist of a LED light source, adjustment plates and a heat sink. The adjustment plates and heat sink where covered in a surface treatment. Theoretical framework A simulation of a finite element model was set up of the current solution in order to identify the influence of the different parts and their thermal properties. The simulation was set up as a steady state thermal model. The FEM and steady state equations used during this are mentioned and shortly explained. The state of modern research was found in order to find new innovative ways of solving the heat problem. Method In order to understand the current solution, experimentswere carried out. Interviews were used in order to get the correct information easily. A literature study was preformed to understand the different theories. Reverse engineering was applied to get a detailed understanding of the functionality both mechanically and thermally. Brainstorming was used to generate new solutions, which was followed by a feasibility evaluation and Pugh’s method to sort out the best concepts. Implementation and Result Based on the simulations it can be concluded that some of the developed solutions pass the requirements and can be implemented right away. Some need some more work in order to fully pass the demands. Conclusions The thermal flow was greatly affected by the properties of the aluminum in the adjustment plates and heat sink, though there was not much room for thickness reduction. However, the oxide layer and the surface roughness also had a great impact on the high junction temperature. The requirements where therefore met when adjustment plates and interfaces were removed, to lower the amount of oxide and air between the LED and the heat sink. But the oxide layers needed to be thinner and the surface roughness needed to be reduced in order to meet requirements. If the oxide layers need to stay at current thickness or the surface roughness cannot be changed, the heat sink needs to be redesigned. The recommended concepts were smaller than the current solution. If this space is utilized with a bigger heat sink, the goals can be met with greater ease. There is also room for improvement when it comes to heat sink heat spreader pattern. Discussion The discussion covers what knowledge which was needed to write this thesis and how different problems that occurred along its path were solved. Sustainability in different ways was also discussed.

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This thesis presents a numerical method of predicting both static and dynamic denting phenomena in automotive body panels. The finite element method is used as a predictive tool to assess panel performance prior to production of tooling. A custom software package has been developed to transform existing finite element forming models into ready-to-run finite element denting models, minimising the effort required to perform dent simulations. Over 50 multi-step finite element models were performed. Each of these models simulated the forming, springback and subsequent denting of either 1. 05mm thick AA5754, or0. 81mm, 0. 93mm or 1. 00mm thick AA6111 aluminum sheet. Experimental validation of dent predictions using this method has shown that the trends in both static and dynamic dent resistance have been captured quite well. These validation studies demonstrated the sensitivity of the results to various parameters such as panel thickness, pre-strain, curvature and thickness, as well as numerical formulation parameters. It has been determined that it is particularly important to use forming data within the denting models for accurate results to be obtained.

An examination of static and dynamic dent resistance of structural panel assemblies representing automotive hoods is described in this thesis. Fabricated panel assemblies incorporating typical components of real automotive parts were tested. The panel assemblies included an AA5754 inner panel using an array of teacup supports and an AA6111 closure panel joined with automotive mastic. The assemblies allowed for parametric assessment of numerous factors affecting dent resistance including: panel thickness, panel curvature, panel support configuration and dent site location. An extensive experimental program evaluated various panel combinations under both static and dynamic denting conditions. The measured results illustrate various trends of the different factors affecting dent resistance. The experimental database allows a qualitative assessment of dent resistance for full-scale automotive parts. The importance of support conditions is highlighted. The influence of mastic thickness is found to be a critical consideration. Numerical simulations of the dent test were undertaken using finite element techniques. The numerical predictions offer varying degrees of accuracy. The quantitative results are limited, due to numerical concerns, but the qualitative trends are generally well captured. As well, the relative importance of the various parametric factors is well represented in the numerical results. The interaction of the components at the teacup supports proved to critical to the predictive ability of the models. The method developed to model the interaction was somewhat limited by the available material models within the numerical code used, but offers promise for improved results in future simulations. The modelling method is readily transferred to full-scale automotive panels for assessment of dent resistance early in the design cycle.

Fire in buildings can have a severe impact in terms of both human safety and potential economic loss. This is especially true in the case of fires of such severity that the building structure is damaged. Concrete buildings are traditionally regarded as safe in a fire situation as concrete is non-flammable and exhibits highly insulating material properties. The majority of current research relating to the impact of fire on structures examines other forms of construction. Research of concrete in fire is generally limited to investigation and testing of individual members in order to understand the often complex interactions exhibited by concrete as a material at high temperatures. This research seeks to redress the balance by using a systematic approach to examine effects of fire on a holistic concrete structure in simplified but realistic temperature exposures. The research utilises evidence and structural information from the Windsor Tower in Madrid, which suffered a major fire in February 2005 with partial collapse in some areas of the structure. The fire spread throughout the building, travelling both upwards and downwards. Computer modelling was used extensively. Computational Fluid Dynamics (CFD) analysis was used to explore likely fire temperature and duration in localised areas. Structural Finite Element Modelling (FEM) was used to develop a hierarchy of models, beginning with simple structural forms and progressing logically to more detailed structures. This produced a systematic and comprehensive analysis of the reaction of the structure to fire for comparison to the real, observable damage to the building and assessment of generic failure behaviours. The structural model produced was used with a number of variations in support condition, fire spread rate and extent, and fire protection. It was found that for a structure of this type, structural stiffness of the concrete floors was insufficient to compensate for the loss of strength in heated steel members where there was no alternative load redistribution path. It was also found that in the case where an alternative load path exists, but involves steel members which have previously heated during the multiple-floor spread of the fire, the rate of fire spread has a critical effect on the structural stability.

Tyréns ABs har utfört stabilitetsundersökningar för fastigheterna Plogen16samtVälten2 och 3 i Umeå kommun. Områdena är attraktiva vid Umeälv och fastighetsbolaget Cityfastigheter i Umeå AB har önskan att exploatera dem. De beaktade områdena innesluts av Tvärån och Umeälv som medför att området får ett komplext utseende. Det finns således två slänter som omsluter områdena, en mot Tvärån och en mot Umeälv. Områdena består främst av silt med inslag av sand och sulfidsilt men mäktighet på 10 meter. Slänten mot Tvärån visade på markrörelse medan den branta slänten mot Umeälv inte visade några stabilitetsproblem. Tidigare utförda stabilitetsberäkningarna av Tyréns AB visade på 13-14 meter säkerhetsavstånd från slänten mot Umeälv. Då områdena är bebyggda närmare än säkerhetsavståndet och då anses stabil när ingen deformation av slänten har kunnat tydas, väcks frågan hur vida 2D-beräkningar är tillräckliga för att beskriva stabiliteten i dessa typer av slänter kring älvar. Det ledde fram till en önskan om att genomföra stabilitetsberäkningar i 3D. Programvara som valdes för att genomföra 3D-beräkningar var PLAXIS 3D. Då de utförda beräkningarna av Tyréns AB genomfördes i programmet SLOPE/W som tillhör programvaran Geostudio bedömdes att beräkningar i PLAXIS 2D vara nödvändiga att genomföra för att en jämförelse skulle kunna ske. Detta för att PLAXIS och SLOPE/W har olika beräkningsmetoder för att beräkna stabiliteten. Beräkningarna genomfördes i PLAXIS 2D för de båda slänterna med dränerad och odränderad analys. Det för att beakta det mest ogynnsamma situationen. 2D-modellen i SLOPE/W replikerades till PLAXIS 2D medan 3D-modellen byggdes upp från en inmätt terrängmodell av områdena. Undersökningarna visade att odränerade förhållanden gav den lägsta säkerheten av slänterna för 2D och för 3D. Resultaten mellan 2D- och 3D-beräkningar påvisade en betydande stabilitetsökning vid 3D-beräkningar. Beräkningarna i 2D, odränerat, genomfördes inte då modellen kollapsade i beräkningsförfarandet, det tolkades som att säkerhetsfaktorn är under 1 för slänten mot Umeälv. För samma slänt i 3D-modellen uppgick säkerhetsfaktorn till 1,48. Den dränerade beräkningen gav i 2D ett brott på 8 meter från släntkrön och en säkerhetsfaktor på 1,2 och i 3D-beräkningen beräknades den värsta brottytan i den strandpromenaden som ligger vid släntfoten av Umeälv. Det tyder på att de tredimensionella effekterna är av avgörande betydelse för stabiliteten. Det är därmed av värde att utföra 3D-beräkningar för komplexa områden.