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:Date donated: July 2007
:Date donated: July 2007
:Summary: Rui Igreja's master thesis at the University of Aveiro, Portugal.<br> Commonly used methods for injection moulding simulation involve a considerable number of simplifications, leading to a significant reduction of the computational effort but, in some cases also to limitations. In this work, Reaction Injection Moulding (RIM) simulations are performed with a minimum of simplifications, by using the general purpose CFD software package CFX, designed for numerical simulation of fluid flow and heat and mass transfer.<br>The CFX’s homogeneous multiphase flow model, which is generally considered to be the appropriate choice for modelling free surface flows where the phases are completely stratified and the interface is well defined, is shown to be unable to model the filling process correctly. This problem is overcome through the implementation of the inhomogeneous model in combination with the free-slip boundary condition for the air phase.<br>The cure reaction is implemented in the code as a transport equation for an additional scalar variable, with a source term. Various transient and advection schemes are tested to determine which ones produce the most accurate results.<br>Finally, the mass conservation, momentum, cure and energy equations are implemented all together to simulate the simultaneous filling and curing processes present in the RIM process. The obtained numerical results show a good global accuracy when compared with other available numerical and experimental results, though considerably long computation times are required to perform the simulations.<br>( <i>A better quality version (6.1MB .pdf) is available from:</i><b> http://sites.google.com/site/ruiigreja2/MyMasterThesis</b> )
:Summary: Rui Igreja's master thesis at the University of Aveiro, Portugal.<br> Commonly used methods for injection moulding simulation involve a considerable number of simplifications, leading to a significant reduction of the computational effort but, in some cases also to limitations. In this work, Reaction Injection Moulding (RIM) simulations are performed with a minimum of simplifications, by using the general purpose CFD software package CFX, designed for numerical simulation of fluid flow and heat and mass transfer.<br>The CFX’s homogeneous multiphase flow model, which is generally considered to be the appropriate choice for modelling free surface flows where the phases are completely stratified and the interface is well defined, is shown to be unable to model the filling process correctly. This problem is overcome through the implementation of the inhomogeneous model in combination with the free-slip boundary condition for the air phase.<br>The cure reaction is implemented in the code as a transport equation for an additional scalar variable, with a source term. Various transient and advection schemes are tested to determine which ones produce the most accurate results.<br>Finally, the mass conservation, momentum, cure and energy equations are implemented all together to simulate the simultaneous filling and curing processes present in the RIM process. The obtained numerical results show a good global accuracy when compared with other available numerical and experimental results, though considerably long computation times are required to perform the simulations.<br>( <i>A better quality version (6.1MB .pdf) is available from:</i><b> http://sites.google.com/site/ruiigreja2/MyMasterThesis</b> )
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*[[Media : MSc_project_report_12-12-12.pdf | External Aerodynamic Analysis of a wheeled Land Speed Record Racing Car using CFD ]]
 
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:Author : Shreyas Ragavan
 
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:Date Written : 1/9/2011
 
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:Date Donated : 14/6/2012
 
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:Abstract : The overall goal of the project was to perform an external aerodynamic analysis of an existing Jet powered Land Speed Record racing vehicle using Computational Fluid Dynamics (CFD). The objective was to study vehicle aerodynamics and setup a simulation and evaluate the parametric sensitivity of the geometry of the LSR vehicle towards the aerodynamic drag. The target speed is just over the Sub - Sonic Range at Mach 0.4 and the simulation condition corresponds to a Reynolds number (Re) of 7 X 10^7. Approximations have been made with the boundary conditions and justifications have been presented. The limited time frame and computational power, has demanded efficiently decomposing the volume mesh and limiting the turbulence models primarily to Reynolds Averaged Navier Stokes (RANS) models. Considering computational power and time available, the total number of cells has been limited to the range of 1.5 million though simulations were run upto 1.98 million cells to investigate grid independence of the solutions. Along with introducing obstacles to make the flow more realistic, mesh morphing/ deformation techniques have been explored, using Optimal Solutions- Sculptor. The scale of the deformations was limited by grid density and computing power. In specific, the effects of varying the geometry of nose and body of the vehicle on the drag have been focussed on. Further, a study of the flow changes when introducing objects around the vehicle with emphasis on the net effect on the overall aerodynamic drag of the vehicle was performed. It was found even minute deformations over the nose orientation and frontal area along with the middle sections of the vehicle seem to display relatively high sensitivity on the aerodynamic drag.
 
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Author's personal website : www.cfdrev.tiddlyspot.com
 

Latest revision as of 11:43, 6 August 2012

Please list all donated documents on this page. For more information on how to donate a text see this page.

Donated texts:

Add more donated documents here

Author: Tony Saad
Date written: Apr 2001
Date Reviewed: Dec 2005
Date donated: Dec 2005
Summary: An introduction to turbulence modeling.
Author: Burley Wang
Date written: Dec 2000
Date donated: Nov 2005
Summary: This is an old Fluent FAQ written by Burley Wang for CFD Online back in 2000. The FAQ was never finished and it was never published either. It is based on questions and answers found on the Fluent forum. Use it to cut-and-paste relevant things from into the Fluent FAQ.
Author: Jonas Larsson
Date written: Dec 1998
Date donated: Nov 2005
Summary: The first part of Jonas Larsson's PhD thesis from Chalmers University, Gothenburg. The thesis excludes papers which are copyrighted by ASME etc. It covers some basics on governing equations, turbine blade heat transfer and descriptions of several low-Re two-equation models (Chien model, Launder-Sharma, Nagano-Tagawa, Shih, ...) The report also includes various model improvements like the Kato-Launder modification, the Yap correction etc.
Author: Ioannis Nousis
Date written: Sep 2000
Date donated: Jan 2006
Summary: The MSc thesis of Ioannis (Yannis) Nousis at the Université Pierre et Marie Curie. The work consists in validating a Reynolds stress turbulence closure on airfoil geometries for transonic compressible viscous flow regimes. Prediction of airfoil aerodynamic performance for several test-cases (NACA 0012 - RAE 2822). Validation of the turbulence model against wind tunnel experiments. A digitized experimental data base is included in the Annexes. Key words: transonic viscous flows, numerical simulation, external aerodynamics, shoc wave-boundary layer interaction, biharmonic structured grid.
Author: Nina Shokina
Date written: May 2000
Date donated: Mar 2006
Summary: The PhD thesis of Nina Shokina (Technical University of Darmstadt, Germany). The work is devoted to the numerical modelling of multi-dimensional steady ideal gas and fluid flows using adaptive grids.
Author: Rui Igreja
Date written: June 2007
Date donated: July 2007
Summary: Rui Igreja's master thesis at the University of Aveiro, Portugal.
Commonly used methods for injection moulding simulation involve a considerable number of simplifications, leading to a significant reduction of the computational effort but, in some cases also to limitations. In this work, Reaction Injection Moulding (RIM) simulations are performed with a minimum of simplifications, by using the general purpose CFD software package CFX, designed for numerical simulation of fluid flow and heat and mass transfer.
The CFX’s homogeneous multiphase flow model, which is generally considered to be the appropriate choice for modelling free surface flows where the phases are completely stratified and the interface is well defined, is shown to be unable to model the filling process correctly. This problem is overcome through the implementation of the inhomogeneous model in combination with the free-slip boundary condition for the air phase.
The cure reaction is implemented in the code as a transport equation for an additional scalar variable, with a source term. Various transient and advection schemes are tested to determine which ones produce the most accurate results.
Finally, the mass conservation, momentum, cure and energy equations are implemented all together to simulate the simultaneous filling and curing processes present in the RIM process. The obtained numerical results show a good global accuracy when compared with other available numerical and experimental results, though considerably long computation times are required to perform the simulations.
( A better quality version (6.1MB .pdf) is available from: http://sites.google.com/site/ruiigreja2/MyMasterThesis )
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