any textbook on Finite Elements can be used for advance study. Some more details on weak forms in COMSOL can be found in the following blog posts:

http://www.comsol.de/blogs/brief-introduction-weak-form/

http://www.comsol.de/blogs/discretizing-the-weak-form-equations/

http://www.comsol.de/blogs/implementing-the-weak-form-in-comsol-multiphysics/

Bettina

]]>If you can also add some references for advance study, that will be great.

Thanks

]]>Thanks you for this great explanation.

I am using the weak form PDE with 2 dependant variables on Comsol 5.0, and I do require two weak expressions (otherwise I get the message : “invalid parameter value : weak expressions cannot be empty”) I am not sure of the second expression I have to use. Do you have any idea ?

Thanks a lot

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