Discussion Forum

hi,

an electric potential applied to a piezoelectric material will cause a deformation of the material. On the other hand a deformation of a piezoelectric material will end up in an electric potential. I'm interested in the latter case, which I will investigate in detail by using COMSOL.

Therefore I have taken a piezoelectric material (pieM) and on that material I put a bimetallic structure (bimS). First, I added an Structural Mechanics Module (SOLID), which is used to set up a thermal change. That will cause the deformation of the bimS and therefore a deformation of the pieM. But now I want to see the induced electric potential inside the pieM. So I added another physics module for piezoelectric devices (PZD). Inside of Piezoelectric Material I defined the "Initial Stress and Strain" by inserting the values for "initial stress" from SOLID in the following form:

S0=((solid.sx,solid.sxy,0)(solid.sxy,solid.sy,0)(0,0,solid.sz)) N/m²

Inside "Linear Elastic Material" I selected the non-piezoelectric bimS.

After computing I can take a look to the electric potential inside the pieM by using the expression "V". But it gives me only one potential for the whole structure. But I found the reason for that: Comsol takes the calculated induced electric potential which leads into an additional deformation. So, what should I do in order to make the induced potential visible and to forbid that this potential ends up in an additional deformation, which is shown up by COMSOL .

I hope that my description won't confuse too much, so that you can give me some hints.

Thanks a lot in advance!

EDIT:
Too make a long story short ;o)
How can I freeze the deformation of the module SOLID (SOLID2 in the file) in order to investigate the piezoelectric potential from module PZD?