CMUT Collapse Voltage Answered

I simulate a CMUT cell and in order to simulate the collapse voltage of the cell, I'm using a contact interface to avoid the touching of the membrane to the electrode. When I apply only pressure, the simulation is good. When I apply DC voltage, the simulation fails due to the error "bad area element". My gap is allocated from i1 to i2 and from j6 to j7 and it's void. Here is the code I'm using. I tried increasing the value of $pstiff but still I have the same problem.

symb ThkGap = 180e-9
symb pclosed = 0.98 
symb pstiff = 140e9 * 1e-3
symb strtgap = $pclosed * $ThkGap

line
    curv cont elas  -$ThkGap -$pstiff  -$strtgap 0.0   0.0 0.0   1.0 0.0
    type joint
    prop gap * * cont  * *  * *  * *  * *  4. 0.04
    itfc gap  $i1 $i2 $j6 $j6 1 1 $i1 $i2 $j7 $j7 1 1 $x1 $y7 0 out
    info length joint

1 comment

  • You can investigate exactly what is happening by plotting the displacement of the elements in the zoomed in area of the location where the bad element is.

    Possible commands:

    This should give some visibility and feedback that will allow you to understand the impact of any changes you are making to the model. You might have to keep increasing the stiffness of the gap or making other changes to the stiffness definition.

    Comment actions Permalink

Please sign in to leave a comment.

Didn't find what you were looking for?

New post