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Alex October 14, 2008 02:46

Blade tip
 
Hello,

I'm trying to simulate the flow arount a rotor blade tip. I'm using the SIMPLE solver and the Spalart-Almaras viscosity model. Boundary conditions are pressure-far-field.

I can't get the continuity to converge. It get's stuck at around 1-2e-4.

What can I do?

Thanks,

Alex

doki October 14, 2008 03:30

Re: Blade tip
 
that is probably related to two things. first, the outer boundaries are not far enough from the inner boundaries. this makes a pressure far field BC hard to maintain. second, the mesh is somehow coarse. especially the aspect ratio,... may not be in allowable range.

Alex October 14, 2008 03:42

Re: Blade tip
 
doki, thanks for the quick reply.

the models size is in x-direction: 15 times the chord length y-direction: 2 times the span length z-direction: 10 times the chord length

From previous simulations I thought that this should be sufficient. I'll try it with the aspect ratio first...


Prasad Dudhgaonkar October 14, 2008 07:39

Re: Blade tip
 
What's your convergence criterion for continuity?

Alex October 14, 2008 08:45

Re: Blade tip
 
I set it to 1e-5


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