## General Mechanical

#### ANSYS APDL COMMANDS

• Abdulsalam
Subscriber

I am working in a project to simulate a Dielectric Elastomer Actuator and I am facing difficulty in how I can apply the voltages and the frequency to the center of the Dielectric Elastomer only, from the top and bottom which represented by the electrodes.

The question I am concern about and I dont know how to do it is;

How I can assign perfect electrodes with zero resistance and negligible thickness that can expand freely without affecting the elastomer actuation? (The Electrodes are placed at the center of the elastomer) The electrodes can expand and back to its original shape very smoothly.

What I am trying to simulate is very similar to the link below it just that my shape is rectangular with the following dimensions, Length =60cm, Width=60cm, electrodes= 20cm in diameter (in the center) and thickness of the Dielectric elastomer is = 0.05cm

• Dave Looman
Ansys Employee
To represent that there is more or less infinite conductivity in the plane of the electrode we can force the voltage to be equal over the surface using coupling:nnsel,s,.... ! Select the nodes of the electrodencp,next,volt,all ! Couple the volt degree of freedom over the electrode surfacennsel,all ! Select all the nodes againn
• Abdulsalam
Subscriber
Dear,nI tried to use the commands (nsel,CP and others) but I still get a lot of errors and I can not get the simulation done. I am learning everything from scratch to be honest and I think I am missing so many important/essentials commands that I am supposed to execute . when I run the simulations I got the following errors; n( *** WARNING*** CP = 52.094 TIME= 17:18:13nThere is at least 1 small equation solver pivot term (e.g., at the UZndegree of freedom of node 87422). Please check for an insufficientlynconstrained model.norn*** WARNING *** CP = 8.531 TIME= 17:55:44nNode 1 on element 1 is unselected. )nI tried to use the commands below to select the nodes but I still get the above errors I mentioned. And if you notice the shape of the electrodes is rectangular which I don't want. I did not know how I can make a circular electrodes that are Parallel to each other from top and bottom.n! positive electrodennsel,s,loc,y,20,40nnsel,r,loc,x,20,40nnsel,r,loc,z,0.5nd,all,volt,3000n! negative/ground electrodennsel,s,loc,y,20,40nnsel,r,loc,x,20,40nnsel,r,loc,z,0nd,all,volt,0) nI will share the command I used so far from the beginning until the end for your reference. This is my first time dealing with ANSYS APDL so I am a bit confused and lost. I have attached the errors generated for you reference.n By the way, I really appreciate your input and help Thank you so much!nnn
• Abdulsalam
Subscriber
Dear,,nI tried the same command you advised me but I still get errors as you can see in the attached photo below and I am unable to solve my simulation. I have attached my commands as well for your valuable feedback. nnReally appreciate your help in this matter.nBest Regards, n