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mark November 23, 2004 15:17

Problem using ideal gas
 
I am running a heat transfer problem and trying to implement the ideal gas equation to model my density. I am using rke two layer model for turbulence. When I use constant density or even incompressible ideal gas, the solution converges nicely in less than 2000 iterations. However, as soon as the ideal gas is chosen, the solution limits the pressure (regardless of what range of pressure values I use). Has anyone else experienced a similar problem?


ROOZBEH November 24, 2004 04:32

Re: Problem using ideal gas
 
Hi; For compressible calculations, it is better to choose "Coupled" solver not "Segregated". Then you should start calculations with a very low courant number in solution panel (for example .001). After several iterations, you can increase courant number to 0.5 or ..., slowly(.001 then .005 then .01 and ...). Hope this help you. ROOZBEH

nabeel mohsin November 24, 2004 07:07

Re: Problem using ideal gas
 
hi have you selected energy equation to solve nabeel

mark November 29, 2004 17:40

Re: Problem using ideal gas
 
yes, I am using the energy equation


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