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Marek November 18, 2008 08:24

Notice in CFX
 
Hi

I am trying to simulate two phase flow in combustion chamber using CFX 10. After few more than 10 iterations I get message: __________________________________________________ __________

Newtons method failed to converge in 100 iterations. This occurred while computing the following variable:

Variable Name : C3H8.Temperature Location Name : fluid Mesh location : VERTICES Mesh entity : Last 3 Changes : 1.50603E+03 1.50603E+03 1.50603E+03 Tolerance : 1.0000E-02

The Newton iteration was either slowly converging or has stalled. The solver will continue with the variable set as it was on the final iteration. If this situation continues you might try increasing the number of iterations allowed for Newtons method. This can be changed by setting one of the parameters:

Temperature : "Constitutive Relation Iteration Limit" Pressure : "Newton Pressure Iteration Limit"

for your mixture using the definition file editor.

__________________________________________________ __________

Soon after first message solver stops. I don't understand how to improve definition file taking into account this notice.

Thanks in advance Marek

Ahmad Al-Zoubi November 18, 2008 08:56

Re: Notice in CFX
 
Dear Marek,

Try to run your case 5 iterations and then check your solution, especially the velocity profile. This problem sometimes occurs because of very high velocities.

Regards

Ahmad



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