|
[Sponsors] |
August 2, 2005, 07:22 |
2-D Model in CFX
|
#1 |
Guest
Posts: n/a
|
Hello, I am curious how to run a 2-d model in CFX5, I understand you have to set an enviroment variable to do it (how ?) and also have your mesh extruded how ? I am still using CFX-build, can any one kindly give a step by step method or point me to some literature and example please. Thanks
|
|
August 3, 2005, 11:24 |
Re: 2-D Model in CFX
|
#2 |
Guest
Posts: n/a
|
Hi there,
as far as I know CFX-5 cannot simulate 2D problems. It will always require a 3D mesh. But you can then use only 1 cell in the direction normal to the symmetry plane, so it is almost 2D. |
|
August 3, 2005, 18:31 |
Re: 2-D Model in CFX
|
#3 |
Guest
Posts: n/a
|
Hi,
You are correct, CFX5 cannot do 2D simulations but you can turn a 2D planar or axisymmetric mesh into a 3D mesh by extruding or rotating one element thick and placing symmetry planes on the front and back faces. The solver then uses the 3D solver on this mesh and the symmetry planes prevent flows in the third dimension. I know the developers have been asked to include a 2D solver in CFX5, I guess it is probably one of the most requested features for CFX. But as there is a work around available and it requires the entire solver to be rejigged it has not been done - alas, a real 2D solver would be very nice and much more efficient. As for your request as to how to generate a 2D mesh in CFX-Build, have a look at the CFX-Community. There are a number of reports on how to do it there. Regards, Glenn Horrocks |
|
August 8, 2005, 15:38 |
Re: 2-D Model in CFX
|
#4 |
Guest
Posts: n/a
|
Hi Glenn,
You mention rotating the 2D model to one element thick, this would make a wedge for axisymmetric problems. How do you deal with the mesh near the axis of rotation (the point of the wedge), surely the mesh cells start to become very distorted with high aspect ratios? This would then probably lead to convergence problems. Regards Paul |
|
August 8, 2005, 18:51 |
Re: 2-D Model in CFX
|
#5 |
Guest
Posts: n/a
|
Hi Paul,
Yes, it does lead to elements with high aspect ratios which can cause convergence problems. This is partly mitigated by the fact that the flow is aligned with the element faces so the high aspect ratio elements are not as bad as when they are in a 3D flow. Regards, Glenn Horrocks |
|
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Use of k-epsilon and k-omega Models | Jade M | Main CFD Forum | 40 | January 27, 2023 07:18 |
Superlinear speedup in OpenFOAM 13 | msrinath80 | OpenFOAM Running, Solving & CFD | 18 | March 3, 2015 05:36 |
CFX Streamline Curvature Correction model | flow.pratish | CFX | 8 | August 29, 2012 18:32 |
Reynolds Stress model in CFX vs Fluent | Tim | CFX | 1 | October 7, 2009 06:19 |
Use of 1 equation turbulence model in CFX 4.3 | Niels Deen | CFX | 0 | July 19, 2000 08:50 |