assembling question

[Ashkan Dorostkar]

Dear all,

I want to solve a system of equation for elasticity and I have an extra term in the my equations which is of the form 

-grad(b.u) 

here "b" is a vector of size DIM and "u" is the displacements with DIM components.

I am a bit lost on how to express this with fe_values. Any help is appreciated and any teaching effort is appreciated more.

Best,

Ali

[Jean-Paul Pelteret]

Dear Ali,

If you apply the product rule to this term, does it then look a little more managable?

Regards,

Jean-Paul

[Ashkan Dorostkar]

Thank you,

This helped a lot. I didn't remember that rule at the moment.

Ali

[Jean-Paul Pelteret]

You're welcome!