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Modeling swelling using Eqauation based Weak Formulation

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Dear all,

Hello. I am new in Comsol for my thesis I was working on a model of swelling and frictional phenomenon. I stuck in Comsol. Following are my equations in weak form:

-S*(test(ux)+test(uy)+test(uz))
(Jac-(1/J0)-ohm*c)*test(p)
cdot*(test(C))-hf*(test(Cx)+test(Cy)+test(Cz))-q*(test(C))
(mu-muext)*test(cb)

I got following error.

Test function column Jacobian cannot be evaluated. weak function must be linear in the test functions

Kindly suggest.

Regards,

Mujtaba

1 Reply Last Post 24.02.2015, 21:40 GMT-5
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Hello Mujtaba Ahmed

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Posted: 10 years ago 24.02.2015, 21:40 GMT-5
Hi I'm new in comsol too,

and I'm struggling with the exact same thing with you

did you have any progress?

I want to know how you set the variable S, Jac, hf.

Thanks,

Regards,

Kang
Hi I'm new in comsol too, and I'm struggling with the exact same thing with you did you have any progress? I want to know how you set the variable S, Jac, hf. Thanks, Regards, Kang

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