Ivar KJELBERG
COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted:
1 decade ago
20.02.2013, 02:51 GMT-5
Hi
have you tried to use the terminal in "terminated" mode, or linked to a RC circuit ?,
Indeed I cannot find any perfect electric conductive layer (in the plane direction to mimic a conductor deposited on a boundary) in PZD
But I wonder if this BC (was there before) has not been replaced with the "floating potential" BC
--
Good luck
Ivar
Hi
have you tried to use the terminal in "terminated" mode, or linked to a RC circuit ?,
Indeed I cannot find any perfect electric conductive layer (in the plane direction to mimic a conductor deposited on a boundary) in PZD
But I wonder if this BC (was there before) has not been replaced with the "floating potential" BC
--
Good luck
Ivar
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Posted:
1 decade ago
20.02.2013, 07:44 GMT-5
If what you want to know is the open circuit voltage of your harvester, I would suggest using a grounded boundary condition for one of the electrodes and a floating potential for the second.
If what you want to know is the open circuit voltage of your harvester, I would suggest using a grounded boundary condition for one of the electrodes and a floating potential for the second.
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Posted:
1 decade ago
27.02.2013, 04:49 GMT-5
Thanks a lot for the comments.
I tried floating potential and terminated boundary conditions. I am plotting electric potential amplitudes of arbitrary points on upper surface of the PZT. My FRF is between 0-200Hz and there are 6 modes in this range (they all can be observed in my measurement point). I attached the plots for:
case 1) Zero charge: It is resulting peaks at every natural frequency and arbitrary points on PZT have different amplitudes at each mode as expected.
case 2) Floating potential case: Arbitrary points on PZT have same amplitude so the uniform potential distribution is obtained. However, there is only one peak on the FRF. I lost the information for the other modes
case 3) Terminated case: In this BC i am getting an error as follows
Undefined value found.
- Detail: Undefined value found in the stiffness matrix.
.There are 1 equations giving NaN/Inf in the matrix rows for the variable mod1.pzd.V0_1
. at coordinates: (0,0,0), ...
and similarly for the degrees of freedom, NaN/Inf in the matrix columns.
I see that floating potential should be working. My question is why is it eleminating the peaks at other modes and resulting in only one peak?
Thanks a lot for the comments.
I tried floating potential and terminated boundary conditions. I am plotting electric potential amplitudes of arbitrary points on upper surface of the PZT. My FRF is between 0-200Hz and there are 6 modes in this range (they all can be observed in my measurement point). I attached the plots for:
case 1) Zero charge: It is resulting peaks at every natural frequency and arbitrary points on PZT have different amplitudes at each mode as expected.
case 2) Floating potential case: Arbitrary points on PZT have same amplitude so the uniform potential distribution is obtained. However, there is only one peak on the FRF. I lost the information for the other modes
case 3) Terminated case: In this BC i am getting an error as follows
Undefined value found.
- Detail: Undefined value found in the stiffness matrix.
.There are 1 equations giving NaN/Inf in the matrix rows for the variable mod1.pzd.V0_1
. at coordinates: (0,0,0), ...
and similarly for the degrees of freedom, NaN/Inf in the matrix columns.
I see that floating potential should be working. My question is why is it eleminating the peaks at other modes and resulting in only one peak?