Initial guess for k & Epsilon

May 2, 2001, 20:43

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

May 3, 2001, 17:39

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

May 8, 2001, 05:11

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

May 2, 2001, 20:43	Initial guess for k & Epsilon	#1
Helal Guest Posts: n/a	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

May 3, 2001, 17:39	Re: Initial guess for k & Epsilon	#2
James Date Guest Posts: n/a	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

May 8, 2001, 05:11	Re: Initial guess for k & Epsilon	#3
joseph Guest Posts: n/a	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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