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-   -   Time Stepping Control (http://www.cfd-online.com/Forums/cfx/19153-time-stepping-control.html)

Dave September 4, 2002 07:16

Time Stepping Control
 
Hi Everyone, I have a question regarding which time stepping methodology to apply to my model. I have a buoyant jet release (approx 170 m/s) into room defined as a Subdomain which has side walls and a top and a bottom, but no end walls. The room is located in a domain which has an ambient wind of 10 m/s blowing parallel to the open ends of my room. My question to the group is:

What would be the best Time stepping Methodology to apply to achieve convergence as quickly as possible ?

I have tried using Auto Time stepping, this unsupprisingly has chosen very small time steps and convergence has not been great. Would I be better to use local time stepping to start with (as there is a large variation in the velocity field) and then swap over to physical time stepping once I've achieved a converged solution ??

Your imput would be most appreciated, Cheers and Thanks

Dave

Nandu September 4, 2002 12:34

Re: Time Stepping Control
 
have u tried using the swap between local time stepping and physical timestepping? I have a similar problem but the jet is a supersonic jet into still air. I have had no success with either physical or auto timestepping. local timestepping has give me a converged solution, the validity of which i still doubt.

regards n menon

Dave September 5, 2002 05:39

Re: Time Stepping Control
 
Hi Nandu, cheers for the suggestion, I'll give it a try. Dave


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