Hello,

I have not work in your field of study but I have a proposition for your problem and I have no idea if it going to work. Anyway, you can go to this section: Study -> Step1:Stationary-> Setting-> Values of Dependent Variables -> Initial Values of Variable Solved for. Then try to change the "physic control" tab to "User control" and change it to "Initial Expression" or "Solution" until you get a better answer.

Or you can right-click on Study -> Solver Configuration and click on "Show default Solver". Then go to "Dependent Variable" tab and click on your variable and go to its "Setting" > "Scaling" > try to change the "method" tab

from "parent" to "manual" and try to change the "scale" to different magnitude until you get a better results.

Regards,

The question is, why you want to model a Piezoelectric response in stationary mode? Are you gonna continuously apply a fixed load on one side of the piezo for ever? even if this is the problem, then what sort of information you would like to extract?.

If you want to see how the structure bends with respect to the applied pressure or force, you shouldn't use piezoelectric module, instead, the solid mechanics module solely will work perfectly; however, if you want to model the generated voltage or charge of the piezo by applying the force, you have to specify an electrical output or 2 electrodes which will take care of the problem. Having said that, I don't understand to model the piezo response in stationary analysis but you can do so of course!

By looking at your model, one can see that you are trying to model the generated voltage by piezo since you have added the electrostatic module. it is lacking boundary conditions. You need to specify ground electrode and floating potential BC to capture the generated voltage.

I did it in your model, and it works. You can take a look at the attachment.

Hello Asef,

Firstly, thanks for your response. Everything is locked in Initial Values of Variable Solved For, I can't click on anything. Moreover, the problem is still here when I am changing the scaling.

------------

Hello Reza,

Thanks for your response too. Firstly, I wanted to let you know that i can't open your attachment because it seems that you did it on a later version of Comsol.

The modelling of the piezoelectric effect is just the first part of the modelling of a micro magnetic sensor using magnetoelectric effect. Here, we just want to see if we can set up a trustworthy piezoelectric model. So, I just want to apply different values of pressure and see if the electrical response is linear.

I tried to fix a ground on a boundary and I am looking into how to set up the floating potential (on which surfaces and the intensity).

Thanks a lot to both of you.

Hello,

I manage to fix the problem by simply inputing an electric ground on the fixed faces. I thought the initial values were here for that but it seems they are only here to define the limit conditions of the mathematical model.

Thanks again !

first time i am working on cantilever beam. my problem is i am unable to find out the conversion from beam deflection to voltage. can anybody suggest me how to get results in voltage when using comsol softwares.