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-   -   Initial guess for k & Epsilon (http://www.cfd-online.com/Forums/cfx/18510-initial-guess-k-epsilon.html)

Helal May 2, 2001 20:43

Initial guess for k & Epsilon
 
Dear All,

Can anyone let me know the best way to set the initial guess values for k and epsilon? What are the related assumptions to set these values? Is their any thumb rule for these? I need this information to set the AMBIENT VARIABLES in my command file.

With regards,

Helal

James Date May 3, 2001 17:39

Re: Initial guess for k & Epsilon
 
Have a look in this book, it should tell you what you need to know.

"An Introduction to Computational Fluid Dynamics", H.K. Versteeg and W. Malalasekera, Longman Scientific and Technical, 1995, 1st Edition, ISBN 0582218845",

Regards James

joseph May 8, 2001 05:11

Re: Initial guess for k & Epsilon
 
hi

The initial condition for the pressure field should be the average of the highest value of pressure specified on any of the Outlet boundaries and the lowest value of pressure specified on any of the Inlet boundaries. This reduces the likelihood of spurious inflow at Outlets, or outflow at Inlets, during the course of the solution.

If you suspect that the flow is predominantly in a particular direction through the domain (for example, in the direction of an Inlet specification), you can set the Initial Guess to these velocity components.

Regards,

joseph


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