CFD Online Discussion Forums

note about convergence

Posted March 26, 2013 at 05:39 by skeptik (CFD notes)

Quote:

Originally Posted by chegdan

Nick,

There are some strategies that I would try to get these residuals down to something you would like.

Lower your pressure relTol by an order of magnitude compared to U i.e. relTol = 0.001 for P and relTol = 0.01 for U.
Without knowing the mesh you are using you may need to increase the nonorthogonal corrector by 1 or 2. if you are using a tet mesh...then there are many things you can do.
Use first order schemes to start with (you will move to higher order ones

...

skeptik

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My cfd learning starts

Posted March 24, 2013 at 23:44 by vijaiaeroastro

Hello fellow cfd fans,
I am starting my deep cfd learning today. i found a material published on finite difference methods and i am going to start from a very simple fluid dynamic problem from today onwards. wish me luck!! :)

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Forgotten post about airfoilmesh. Domain shape

Posted March 22, 2013 at 05:00 by skeptik (CFD notes)

First time i tried domain like this

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And i got no good results cause pressure distribution shown problems with BC

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I tried to make a circular domain like in this work shown in the next figure

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and only with circular domain i get physically reasonable results.

other figures about mesh i used to

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PISO's last results

Posted March 14, 2013 at 07:39 by skeptik (CFD notes)

SIMPLE showed better results.

May be it was caused by mesh. Tetra mesh with lower y+ shows similar results. Quad+tri 3D extruded mesh did not demonstrate good Cx, Cy.

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OpenFOAM Installation for Multiple Users

Posted March 9, 2013 at 09:26 by Hisham (Notes for OpenFOAM!)
Updated March 10, 2013 at 10:47 by Hisham

Tags install, multiple users, openfoam

If OpenFOAM was installed on a single user account using the OpenCFD binaries then for another user to have access to it is very simple. All one needs to do is to add an alias of the installation in the new user's .bashrc file

Code:

OFver='source /opt/openfoamver/etc/bashrc'

If, on the other hand, OpenFOAM (or OpenFOAM-ext) was compiled on a user account (say the user name is MrX) and a new user (MrY) wants to use the same installation, then:

1. MrX must make sure...