Sökresultat:
499 Uppsatser om Fluid simulation - Sida 3 av 34
Migration of a very large database with Swedish demographic data, using Microsoft SQL Server
SMC is in the process of developing a micro simulation model. The existing micro simulation model developed at Cornell University for US data, CorSim, is one of the fundamental parts for the new micro simulation at SMC. To develop the Swedish model, Swedish data on all individuals in Sweden during 11 years are also available. These data are organized in a database. This paper describes the process of rebuilding the database to a more useful structure.
Simulering av simulinkmodeller medExtended Kalman FilterTidsoptimering av integrering
Simulation of different systems can be done using a graphical model description of the system based on block diagrams. The simulation software Matlab/Simulink offers a lot of possibilities to describe a huge number of systems, which can be linear as well as nonlinear. The simulation using Matlab/Simulink is done by integration based on different kinds of numerical methods.When nonlinear Simulink-models are simulated, it is often interesting to apply a Kalman filter to handle the noise that may occur within the process as well as corrupting the measurement. However, application of such a filter leads to an extensive time-consumption despite using fast computers. The reason is that the existing Matlab functions are not constructed for time optimal evaluation.
Modellering och simulering av hovrande helikopter
At the department of Electronic Warfare Assessments at the Swedish Defence Research Agency in Linköping one of the activities is modelling and simulation of the duel between a robot and a target. The aim with this Master's thesis is to develop a simulation model of an hovering helicopter. First a theoretical description of the forces and moments acting on an helicopter is given. Then the equations of motion are derived. These equations are simplified to be valid only for a hovering helicopter and the result is a mathematical model.
Utveckling av en dynamisk Simuleringsmodell av en skotare
The predominant forestry harvesting method is based on the harvester-forwarder method, theharvester folds, branches and cuts trees, and sorts the logs into piles, while a forwarder transportsthe logs to a landing area.This master thesis work is about realization of a dynamic forwarder simulation model, and itspurpose is to provide an integrated forwarder simulation model in MATLAB/SimMechanicswhere the forwarder is based on a concept using pendulum arms to connect wheels and chassis.Active suspension control is developed and implemented into the simulation model, and finallycompared in simulation with passive suspension.In a first step, an integrated forwarder simulation model is developed, containing a simplifiedforwarder model, a tire-to-ground interaction model and a test track model. The simplifiedforwarder model is based a rigid multi-body system with a spring-damper suspension of thependulum arms. The tire-to-ground interaction model calculates the reaction forces, friction fromthe ground and applies the propulsion force. The test track model is a simplified version of thereal test track in Skogforsk. The propulsion wheel torque control is used to regulate theforwarder speed.
1-D Modellering av Piezoelektrisk Injektor
A piezoelectric injector was modeled, in this Master Thesis Project which was carried out at Scania CV AB in Södertälje, in GT-Fuel. GT-Fuel is simulation program from Gamma Technology.The simulation model for the piezo injector was divided into a hydro-mechanical system and an electrical system (Piezoelectric element). First the hydro-mechanic model was duplicated from Advance Continuous Simulation Language model (ACSL). The simulation results were then compared to the ACSL, to verify that the hydro-mechanical system was modeled correctly. The simulation results for the electrical model were also compared with a Simulink model.
TRIM : ? Metod för att identifiera risker och uppskatta projekttider
ITT Flygt is a world leading company that mainly manufactures submersible pumps. A problem of ITT Flygt is that product development projects rarely manage to hold the estimated project time. It shows that something unexpected occurs in projects quite often, which results in delays. The delays can both be due to an optimistic time plan of projects and risks in product development projects which are not discovered at an early stage. This added with unforeseen delays makes it difficult for ITT Flygt to estimate the duration of their projects.The goal with the Master thesis is to examine a suitable method for simulation of project time.
Simulation driven design : An iterative approach for mechanical engineers with focus on static analysis
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.
Simulering av simulinkmodeller med Extended Kalman Filter
Simulations of simulink models using Kalman filters are often very time-consuming. This problem depends mainly on the fact that the Kalman correction has to be performed at each sample instance through the whole simulation. The goal for this thesis work is to reduce that time-consumption for the filtering part (the integration partis treated in a complementary report) of a simulation. Furthermore a Matlab routine to perform parameter tuning and finally a graphical user interface is developed.The filtering part of the simulation in this thesis is based on an Extended Kalman Filter (EKF). The time optimization of this filter considers searching for the possibility to replace the today?s existing Matlab functions that is used to perform the filtering calculations.
En fordonsförares upplevelse av accelerationer som grund för en effektiv simuleringsmodell
Saab Aerosystems has a long tradition and a lot of competence in the field of flight simulation. Their ambition to broaden the market horizon has led to a discussion about also selling vehicle simulation solutions, both for military and civilian use.The aim of this thesis is to investigate the driver?s experiences of the accelerations he or she is exposed to whilst driving in rough terrain. The results may be used as a basis for future decisions and can act as a platform for the construction of an effective simulation model.To investigate the driver?s exposure of acceleration, some kind of dynamic simulation is needed.
Simulation driven design : An iterative approach for mechanical engineerswith focus on modal analysis
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.
Beräkningar av marknadsrisker: teori samt metoder i utvalda
program
Det här examensarbetet förklarar i olika stor utsträckning några av de vanligaste riskmåtten för marknadsrisker. Störst fokus får Value at Risk och de tre vanligaste metoderna att beräkna detta: Historisk simulation, Varians-Kovariansmetoden och Monte Carlo-simulation. Utvalda riskmått och funktioner har dessutom undersökts och förklarats för tre olika mjukvarupaket designade för att beräkna risk. Skillnader i programmen har lyfts fram, dissikerats och diskuterats..
Hur enkel- & dubbelportsturbin i kombination med två olika avgassamlare påverkar gasväxlingsprestanda på en Scania V8
The exhaust arrangement on a Scania V8 consists of one manifold at each bank connected to a twin entry turbine (8-2-2). A study in GT-Power has shown improved performance and reduced cylinder to cylinder variations using two manifolds at each bank in combination with a single entry turbine (8-4-1). This thesis work analyses the difference in performance shown in simulation and verify it by engine test.The initial work was focused on simulation in GT-Power. Investigating how exhaust manifold volume and pulses effects the turbine efficiency and the mean effective pressure during the gas exchange. To verify GT-Power simulations four engine tests with different exhaust arrangement have been made.The results from GT-Power simulation indicate that a larger exhaust volume improve the turbine efficiency.
Modellering av Panna 5 Mälarenergi AB : utveckling av en beräkningsmodell med simuleringsverktyget IPSEpro
Heat and power stations are often in need of optimizations. A simulation model is a tool for findingways to optimize the plant. The scope of this diploma work is to develop a simulation model ofBoiler 5 at Mälarenergi AB. Boiler 5 is a circulated fluidized bed boiler that was taken into service inyear 2001. Among the included parts in the boiler are cyclone, convection part andINTREX-chambers.
Jämförelse av olika reglersystem för undervisningsändamål
Examensarbetet syftar till att jämföra nya alternativ till olika system för användning i laborationer i reglerteknikkurser för olika studentkategorier. Det skall utredas vilket av ett antal alternativ till mjukvaruplattformar som är bäst lämpat att användas vid reglerteknikundervisningen i ITN:s reglerlaboratorium vid Linköpings universitet. Tidigare laborationer i berörda kurser skall även modifieras så att dessa kan genomföras i de nya systemen.Examensarbetet resulterade i en rad modifierade laborationer och system att tillämpa i dessa. De nya systemen medför att all reglering sköts direkt från en dator istället för tidigare variant med externa apparater som programmeras. På så sätt kan större fokus läggas på regleringen i sig och inte de system som tillämpas för att utföra den..
Vision eller Verklighet ? Vad säger kontoret om företaget som sitter där?
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.