This thesis deals with the numerical 3D simulation of a four stroke, spark-ignited, internalcombustion engine, which is mounted on a high performance motorcycle. The work, carried outin collaboration with Politecnico di Milano and MV Agusta, focuses on the simulation of theintake, compression and expansion stroke, including combustion simulation, using an opensource CFD code.Simulation of internal combustion engines offers a great challenge in the field of CFD research.Moving boundaries of the solution domain, caused by the motion of the piston and valves, leadsto deformation of the computational grid, with decreasing quality of the solution as result. Basedon this, a previously developed mesh motion strategy was employed where a number of meshesare used to cover the whole simulation cycle. Within each mesh interval the internal cell pointsof the mesh are moved to account for the boundary motion of the piston and valves. This strategywas previously applied to simplified geometries as well as real engine geometries.

This thesis of 15 hp has been implemented at Halmstad University, in collaboration with Saab Dynamics in Linköping. Saab Dynamics is a company operating in the defence industry where competition is tough. This necessitates new ways to increase efficiency in the company, which is the basis for this thesis. Saab Dynamics wants to introduce simulation driven design. Since Saab Dynamics engineers have little experience of simulation, required a user methodology with clear guidelines.

This study deals with the technical and economic feasibility of replacing the nuclear power plant reactor Ringhals 3 with a biofuel power plant. A technical investigation has been executed to determine which of the systems and components that could be reused and which ones would need to be replaced. The investment costs of the reconstruction have also been estimated. The cost of the electricity production has been calculated as well as the emissions of the new biofuel power plant. Based on the established rate of return, the lowest average spot price of electricity that makes the investment profitable has been calculated.

This study was carried out as a commission from Holmen Skog, district ?Egen skog? in Norrköping. During October 2006 several stands were inventoried by aerial photos from helicopter. The stands were those for which the next action proposed was plant inventory or plant check. The photos were interpreted and the number of stems was calculated.

This thesis of 15 hp has been implemented at Halmstad University, in collaboration with Saab Dynamics in Linköping. Saab Dynamics is a company operating in the defence industry where competition is tough. This necessitates new ways to increase efficiency in the company, which is the basis for this thesis. Saab Dynamics wants to introduce simulation driven design. Since Saab Dynamics engineers have little experience of simulation, required a user methodology with clear guidelines.

This study examines the use of building modeling and energy simulations in the design process  of  a  building.  The  take-off  point  is  the  notion  of  energy  simulations  being needed early and throughout the building design process, and that the lack of energy simulations may be explained by the fact that they are time consuming and therefore often too expensive. A greater interoperability between software tools used by relevant disciplines,  such  as  the  architect  and  the  energy  specialist,  would  create  smoother workflows, which would reduce this cost and open up for more frequent and iterative energy  simulation  processes.  The  study  is  an  assessment  of  the  modeling  tool  Revit and  the  simulation  tool  Virtual  Environment  and  whether  they  can  create  smoother workflows, and make leeway for a more frequent use of energy simulations throughout the  design  process.  It  also  investigates  the  limitations  of  what  can  be  examined  by simulations in Virtual Environment. This will hopefully help clarify the future role of energy  simulations  in  design  processes.  The  method  is  a  trial  by  error  approach  of testing the two software tools by building and simulating a model. The results of these tests  show  that  the  workflow  is  not  optimal  (and  therefore  time  consuming)  for frequent  and  iterative simulations  throughout the  design  process,  but  it  also  reveals some  great  possibilities  of  what  can  be  performed  with  these  two  powerful  tools  at hand.  Further  development  with  regards  on  platform  independency  of  the  building information  model,  including  seamless  exporting  and  importing,  seems  necessary  to strengthen the future role of energy simulations..

A key part in the development and verification of digital systems is simulation. But hardware simulators are expensive, and software simulation is not fast enough for designs with a large number of gates. As today?s digital zesigns constantly grow in size (number of gates), and that trend shows no signs to end, faster simulators handling millions of gates are needed. We investigate how to create a software gate-level simulator able to simulate a high number of gates fast.

This thesis of 15 hp has been implemented at Halmstad University, in collaboration with Saab Dynamics in Linköping. Saab Dynamics is a company operating in the defence industry where competition is tough. This necessitates new ways to increase efficiency in the company, which is the basis for this thesis. Saab Dynamics wants to introduce simulation driven design. Since Saab Dynamics engineers have little experience of simulation, required a user methodology with clear guidelines.

With background in the rapidly growing need to find solutions for sustainable energy production and the increasing interest for wind power, this report was written. With take-off point from the wind power plant Big Glenn, which has been built in the harbour of Gothenburg, a model of the adjacent power grid has been created in Simulink/SimPowerSystems. Parameters for the power grid and its components has been provided by Göteborg Energi Nät, that has also been the supplier of measurement data of produced power, the power need from loads in the vicinity, voltage levels, current values and also the variation of power factor at the wind power plant.The SimPowerSystems model has been used to perform simulations of power flow in the grid. These simulated values have then been compared to the measured values to verify the functionality of the model. Further, the model has been used to perform simulations of a grid fault, which causes a voltage drop.

The Rya power plant in Borås produces district heating, district cooling and electricity. The plant is owned by Borås Energi och Miljö AB and is run by Dalkia Facility Management AB.In order to get the best heat exchange from the district hot water a pair of twin pumps and a turbine circuit pump are used as return pumps. Turbine circuit pumps are used to increase the pressure through the heat exchangers at the power plant. The pumps are in use when the flow is over 2 000 m3 h-1 and during the summer when re-cooling is used to improve the effectivens of the heat boilers.Since the pumps, that are parallel connected, rotating at a fixed rate per minute, the pressure is regulated with regulating valves. This report shows that during the 4,300 hours that the pumps where in use, energy corresponding to 590 MWh was wasted.

This thesis of 15 hp has been implemented at Halmstad University, incollaboration with Saab Dynamics in Linköping. Saab Dynamics is a companyoperating in the defence industry where competition is tough. This necessitatesnew ways to increase efficiency in the company, which is the basis for this thesis.Saab Dynamics wants to introduce simulation driven design. Since SaabDynamics engineers have little experience of simulation, required a usermethodology with clear guidelines. Due to lack of time, they chose to assign thetask to students, which resulted in this thesis.The aim of the thesis is to develop a methodology in mechanical design, wherethe designer uses the FE analysis early in the design process to develop thestructures' mechanical properties.

With background in the rapidly growing need to find solutions for sustainable energy production and the increasing interest for wind power, this report was written. With take-off point from the wind power plant Big Glenn, which has been built in the harbour of Gothenburg, a model of the adjacent power grid has been created in Simulink/SimPowerSystems. Parameters for the power grid and its components has been provided by Göteborg Energi Nät, that has also been the supplier of measurement data of produced power, the power need from loads in the vicinity, voltage levels, current values and also the variation of power factor at the wind power plant.The SimPowerSystems model has been used to perform simulations of power flow in the grid. These simulated values have then been compared to the measured values to verify the functionality of the model. Further, the model has been used to perform simulations of a grid fault, which causes a voltage drop.

This thesis has been a part of Forsmarks Kraftgrupp AB's evaluation of a turbulencemodel used in simulation of turbulent flow called PRNS (Partially Resolved NumericalSimulation). This model has promising properties and may be of use in savingcomputational resources. The purpose of this thesis was to analyze this model andcompare it with industrially applied models such as k-omega SST and LES (Large EddySimulations).PRNS works as a hybrid of the k-omega SST and DNS (Direct Numerical Simulation)where a constant, RCP (Resolution Control Parameter) with a value between 0 and 1are selected. This constant is then used in the calculations and determines thebehavior of the simulation. When RCP is set to zero the equation are the same as fora DNS simulation and when RCP is set to one the equations for k-omega SST issolved.

This study has investigated how urban vegetation can be used in a multifunctional way to support ecosystem services in urban environments. Nacka municipality is in the start-up phase of building what is to become Nacka city. This provides a unique possibility to study and analyse what role the vegetation play in making the city a healthy living environment and how it needs to be adapted in order to be resilient against changing climate conditions and how the effects of those changes can be regulated. The study further investigates how airborne pollution, caused by urbanization processes, can be regulated or reduced by vegetation or species selection. Methods used in this study were a combination of qualitative interviews and literature studies, seeking to answer the questions: Which specific ecosystem functions are needed in the urban environment and which aspects will influence the ecosystems ability to deliver the functions in demand? And which plant species have the right mechanisms needed to deliver those functions? These questions have been studied and analysed in a local based context where the local conditions ands site specific needs of Nacka define criteria for plant selection.

This thesis of 15 hp has been implemented at Halmstad University, in collaboration with Saab Dynamics in Linköping. Saab Dynamics is a company operating in the defence industry where competition is tough. This necessitates new ways to increase efficiency in the company, which is the basis for this thesis. Saab Dynamics wants to introduce simulation driven design. Since Saab Dynamics engineers have little experience of simulation, required a user methodology with clear guidelines.