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Time dependent Navier Stokes does not converge - inlet boundary condition

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Hi all

I am modelling a laminar flow problem in a micro channel in a transient mode. My model works well
but when I change the inlet boundary condition to velocity instead of pressure it does not
converge! the outlet is pressure boundary condiiton

I get below message

Nonlinear solver did not converge.
Maximum number of Newton iterations reached.
Time : 0
Last time step is not converged.

Also when I change the viscosity to non newtonian, my model only works with velocity
inlet boundary condition and not the pressure?


Can you please comment?

Regards
Abe

0 Replies Last Post 2014年6月7日 GMT-4 05:24
COMSOL Moderator

Hello Abraham Mansouri

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