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Jackie January 21, 2003 05:16

momentum source
Hello, All

Does anyone know,can I create the plane source of momentum in CFX5.5.1 and how to do this.

Thanks in advance,


Roman January 22, 2003 06:15

Re: momentum source
Hi, Jackie

I have at the moment a similar problem with CFX 5.5.1. I want to create a plane mass source. I thought about a very thin subdomain at best only one element thick. Do you know how to create such subdomain with a acceptable number of elements, that's mean without using very small elements.

Bye, Roman

Jackie January 22, 2003 23:17

Re: momentum source
Hi Roman

You may apply stretch in mesh parameter but I'm not sure that it'll work with subdomains. The another way is using PI (Paving and Isomeshing). PI allows you to create surface mesh in a piecewise manner as you constructed your geometric surfaces.Furthermore you can also mesh different surfaces using different length scales. See 'Introduction to Paving and Iso Meshing' in your online help.

goodluck, ^_^


Bob January 24, 2003 09:17

Re: momentum source
Can I ask why you want to model a plane momentum source ? Is it like a sheet of momentum, similar in a war to the uints you have above a door in a shop to keep the cold air out ? Bob

Jackie January 26, 2003 05:22

Re: momentum source
Hi Bob

Yes, I think the meaning of my momentum plane source are the same meaning of your sheet of mometum. I'd like to simulate a flow through a very thin turbine call actuator disk, so to simplified the problem. I instead the thin turbine with an actuator disk. (The actuator disks mean the surface that able to add a momentum immediately to fluid when fluid flow through them . Could you give me any suggestions please.

Kind Regard Jackie

Bob January 27, 2003 06:51

Re: momentum source
Jackie, the only suggestion I can make is a very thin subdomain. You could put a whole series of point sources, but I don't think that would be a very good approach. I think the thin subdomain may be the only approach. You may be able to improve things by creating a structured mesh for the subdomain, then join the 2 using the GGI tools ?? Bob

Bob January 27, 2003 06:52

Re: momentum source
Ps I'd try it both ways just to check the difference in the 2 methods. Unstructured may take more cells but the answers may be more correct ?

Jackie January 31, 2003 02:13

Re: momentum source
Thank you very much bob.

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