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John April 5, 2003 23:56

compressible
 
hi everybody, im a student in uk, and as my final year project i have to simulate in ansys the flow within a convergent divergent nozzle, using ansys. i am having problems with convergence. I begin with artificial viscocity such as 10 or 100 and gradually reduce it to 0 after a 100 iterations, but i have no idea what else relaxation i should apply to get my convergence better. And the help file of ansys is a big mystery and its so difficult to find any documentation about this subject, so i thought about posting here. Any help would be great or just tell me what to read.... thanks

john April 6, 2003 12:35

Re: compressible
 
i get to values as low as 1e-4 for pressure and vx.If i understand correct i should be aiming at values as low as 1e-8?? Also the only boundaries i apply is an inlet and outlet pressure. The problem is i get quite similar pressure distribution to the theoretical one, however i should be getting lower pressure values in the throat of about 100kPa and im not, (thats a big difference isnt it?)


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