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Strange errors about several "uncorrelative problem".

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Hi, everyone

I am in trouble when solve PDE problem. There are 5 sets of couplied PDEs and 8 boundary conditions, and a term of "(u1/u2)^0.5" is in one of the eqations.

Then whether there must have 10 boundary conditions for 5 sets of PDEs (2:1)?

The strange error is show below.

1. When I remove 2 boundary conditions, i.e, the number of conditions now is 6, Comsol would cue that: "Failed to evaluate expression" when solving, that mean that the expression of "(u1/u2)^0.5" is wrong.

2. When I sovle the 5 sets of couplied PDEs with 8 boundary conditions, the result can be received even if it is not so good. Then how the wrong of "(u1/u2)^0.5" disappear ?

So weather the term of "(u1/u2)^0.5" is wrong? How to handle the number of boundary conditions? How to treat the PDE problem?

Could anybody guard me a alternative way?

Thank you very much!

youf.

0 Replies Last Post 2010年10月9日 GMT-4 22:30
COMSOL Moderator

Hello youf Blue

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