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#1 |
New Member
anonymous
Join Date: Nov 2009
Location: Switzerland
Posts: 8
Rep Power: 16 ![]() |
Hi everyone,
recently i tried to use potentialfoam for getting a better initial-velocity field for further simulations. But i made the a strange, totally unphysical (or at least i think so ![]() ![]() First i thought that sth is wrong with my settings. But then i observed the same effect in the tutorial case pitzDaily. So with: outlet { type fixedValue; value uniform 0; } i obtain a max. velocity of about 27m/s ![]() But with: outlet { type fixedValue; value uniform 100000; } the max velocity is 1e6 m/s ![]() As far as i know the velocity in a potential flow shouldn't be affected by the reference value of the pressure. Has sb an idea what's wrong? Is it eventually a bug in potentialFoam (i briefly looked in the code, but everything look nice to me) ? If sb experienced the same effect, is there a better work around than just shifting the pressure to zero (and back..)? thanks for your answers |
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#2 |
New Member
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Hello. I've tried something similar but I was looking for the U field. Have you used into an airfoil too?
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#3 |
New Member
Join Date: Aug 2010
Posts: 11
Rep Power: 16 ![]() |
What are your inlet boundary conditions? From the tutorials I think they're zeroGradient with an outlet boundary condition of 0. If I understand the problem, it's trying to have an initial pressure of 1e6 Pa at one end and 0 Pa at the other (the whole pressure is uniform 0 at t=0), which is understandably hard to solve. Do you know your inlet/outlet boundary conditions well? Can you try putting in those pressures and seeing how that works out? How about trying to have the whole pressure at something closer to 1e6?
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