a******n
发帖数: 98 | 1 Use ANSYS to calculate the stress of a piezoelectric plate. The transverse
stresses(Szz,Sxz,Syz, where z is the thickness direction of the plate) on
the free surface where no forces and pressure are applied are not zero, and
the magnitude is not too small to be neglected. I have verified that the
displacements in three direction are correct and the mesh can not be refined
due to the node limit of this software.
I also checked other structures(nonpiezoelectric plate, beam), the
transverse str | S***s
发帖数: 67 | 2 I have run a S-S-S-S plate (dimension 1.0x1.0x0.2) problem with uniform
pressure (P=10,000) applied at the bottom surface.
Case 1. 20x20x10 linear elements (solid45)
The value of Szz at the center of the top traction-free surface is -286.94,
around 1% of the maximum Szz, and around 3% of the Szz value at the center
of the bottom surface, which is -9713 (should be -10,000 analytically).
Case 2. 20x20x15 quadratic elements (solid186)
The value of Szz at the center of the top traction-free surface | a******n
发帖数: 98 | 3 Thank you for the time and efforts in answering my questions!
I tried the case of elastic plate you used. The result is better in elastic
plates. As for my problem, I have the coupled electromechanical field. My
result is not so good. The nonzero transverse normal stress Szz on the free
surface is more than 10% of the maximum value in the whole plate. I guess it
may be caused be the large electric field at that point Ez, which is
related to the calculation of stresses.
In addition, I found out t | S***s
发帖数: 67 | 4 I have run a S-S-S-S plate (dimension 1.0x1.0x0.2) problem with uniform
pressure (P=10,000) applied at the bottom surface.
Case 1. 20x20x10 linear elements (solid45)
The value of Szz at the center of the top traction-free surface is -286.94,
around 1% of the maximum Szz, and around 3% of the Szz value at the center
of the bottom surface, which is -9713 (should be -10,000 analytically).
Case 2. 20x20x15 quadratic elements (solid186)
The value of Szz at the center of the top traction-free surface | a******n
发帖数: 98 | 5 Thanks for the reply.
1.I used solid226 element for the coupled field analysis. For the 3-D volume
mesh, there are nodes on the free surface. So, I evalue the stresses by
nodal value. Yes, the stresses are more accurate at Gauss points, but how
can we evaluate the Gauss point stresses in ANSYS?
2.The transverse normal stress Szz on the free surface is larger at the
location where plate deflection is larger. This might be caused by what you
said " high stress gradient". I don't know how to deal w |
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