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rotationary physics, weak constraint, lagrange multiplier
Posted Dec 9, 2011, 7:17 a.m. EST Version 4.2 0 Replies
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I am modelling a 2D and 3D model of an induction motor. For this I am using Comsol Multiphysics 4.2 version.
2D modelling:
I am using the rotationary machinery physics and a time dependent solver. I have used an 'identity pair' in the boundary between the stator and the rotor and have also added a 'continuity' boundary condition on the same boundary. For accurate flux calculation I have selected the 'bidirectional weak constraint' on the same continuity (as, I read somewhere in this forum that adding a lagrange multiplier (or weak constraint) gives accurate flux).
Now, when I don't use the 'weak constraint' I get a solution pretty fast ( in couple of minutes), but the flux does not seem to be correct. And when I use the 'weak constraint' as described above, the solution takes a lot of time ( more than 20 hours) and then I get nothing but a error message saying ' Time Dependent Solver did not converge'.
I am not being able to figure it out. I have a strict deadline and its very important to finish this model as soon as possible.
Please help me guys!
Hello uGrachaNda
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