×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

modeling of a piezoelectric composite plate

modeling of a piezoelectric composite plate

modeling of a piezoelectric composite plate

(OP)
Use ANSYS to analyze a piezoelectric composite plate:

Is there any way of inputing the material matrices of piezoelectric composite before transformation and then add an angle? I searched for the elements of
the structural layered composite, and they don't have the DOF of voltage-that's why I can not use this kind of elements. So, the only way is to input the material matrices (elastic, piezoelectric and dielectric matricex) after transformation?  

Because I need to keep the DOFs of three displacements and voltage, I can only choose SOLID5 as the element type. It causes a problem that I can not mesh a thin plate with small size elements-the thickness of the plate can not be
divied up to the requirement of accuracy. How to solve this problem?

Appreciate your reply!

RE: modeling of a piezoelectric composite plate

Hi

It looks like you want to do an Coupled-Field analyse.
So you need to take an look at that.

Gtrz
Garry

RE: modeling of a piezoelectric composite plate

(OP)
Thank you! I've read through the part of coupled-field analysis, but I can not solve my problem.

RE: modeling of a piezoelectric composite plate

Hi

You want to model piezoelectric composite, and look at the displacemants what are caused by Volt?

You can make this work by using an struc-elek coupled-field analyse with an shell element.

Grtz
Garry

RE: modeling of a piezoelectric composite plate

(OP)
Thanks! I have to use 3-D elements because I need to calculate three displacements and voltage. Then, I got too many DOFs for a thin plate and the thickness can not be discritized by enough nodes.

RE: modeling of a piezoelectric composite plate

I'm not quite sure if I understand the question but you can use SOLID98 elements and change one of the keyopts to give you ux,uy,uz and volts DOFs only.  

RE: modeling of a piezoelectric composite plate

Hi

The solid98 is the high order elemnt of solid5. And it will not help him. The best thing for him to do is to use a shell element( because of the thin elements).

Grtz
Garry

RE: modeling of a piezoelectric composite plate

(OP)
Thanks for the reply! I need to have the DOFs: Ux, Uy, Uz, Volt. And the version of ANSYS I used can not handle more than 256,000 nodes. For the thin piezoelectric composite plate which is made of several layers of piezoelectricity with different layer-up angles, the simplest element I can use is SOLID5. I read through the elements for modeling layered composites(SHELL99, 91, 181 etc.). They don't have have DOF of voltage.   

RE: modeling of a piezoelectric composite plate

Hi

There are two ways of doing it:
-using solid element 5/98, with this element you can do an direct coupled analysis, but when your volume is very thin you maybe get bad results. Also it is easier to model.
-using shell elements, with this element you can model thin elements. Disadvantage you need to do and couple-field analysis. Its also difficult to model the layers. Advantage is the amongt of elements which can be very low. So you decide what you want to do!

Grtz
Garry

RE: modeling of a piezoelectric composite plate

Hello!

I got an ANSYS error message, which consequence is still unclear to me:

Specified constraint not allowd on slave DOF in coupled set. Coupled set No.1 First node=2 Slave node= xxxx DOF=volt
Move constraints to first node or remove coupling and constrain all.

Does anyone can give me a hint, where to find some more information concerning this error message? Or can anyone explain me the backgrounds of this error?

Thanks

Alex

RE: modeling of a piezoelectric composite plate

Sorry....that was the wrong placement of my message..

alex

RE: modeling of a piezoelectric composite plate

(OP)
ansysfreak, thanks for the post!
I used the direct method to model the thin structure and can not get good results. I don't quite understand what you said about the second method (sequential method). I only apply electric potential to the plate. How can I model with shell elements without the DOF of volt?  To do a piezoelectric analysis, the manual have specialized six kinds of elements:
plane13/223, solid5/98, solid226/227.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources