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Moving surface charge - pzd model
Posted Nov 25, 2013, 6:07 a.m. EST Version 4.3b 1 Reply
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Hello
I tried to build a simple test model of an oscillating surface with an applied surface charge (with pzd model).
The solution shows that the surface oscillates correctly (displacement plot). But when I plot the potential no movement is shown. Furthermore, when i evaluate the potential at a fixed point in space near the charged and oscillating surface, the potential remains constant, as if the surface doesn't move at all. I would expect to see the potential oscillate with the same frequency as the surface.
Does anyone know what i am doing wrong?
Model is attached...
Thanks in advance
I tried to build a simple test model of an oscillating surface with an applied surface charge (with pzd model).
The solution shows that the surface oscillates correctly (displacement plot). But when I plot the potential no movement is shown. Furthermore, when i evaluate the potential at a fixed point in space near the charged and oscillating surface, the potential remains constant, as if the surface doesn't move at all. I would expect to see the potential oscillate with the same frequency as the surface.
Does anyone know what i am doing wrong?
Model is attached...
Thanks in advance
Attachments:
1 Reply Last Post Dec 5, 2013, 6:01 a.m. EST
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Posted:
1 decade ago
Dear Mr. Hansen,
please note that you can plot the deformation, but the material does not follow the deformation. In other words, the geometry frame and the material frame use the same coordinate system (see the chapter "About Frames" in the documentation). So, if you track the solution at a fixed point, it remains constant.
The material follows the deformation in case a "Deformed Geometry" interface is used or the "include geometric nonlinearity" is checked for a structural mechanics interface. Another solution is to manually evaluate the solution at the coordinates (x+u(x,y),y+v(x,y)). Here the spatial at operator may be of help (chapter "Operators, Functions, and Constants" in the documentation).
Best Regards
Bettina Schieche
please note that you can plot the deformation, but the material does not follow the deformation. In other words, the geometry frame and the material frame use the same coordinate system (see the chapter "About Frames" in the documentation). So, if you track the solution at a fixed point, it remains constant.
The material follows the deformation in case a "Deformed Geometry" interface is used or the "include geometric nonlinearity" is checked for a structural mechanics interface. Another solution is to manually evaluate the solution at the coordinates (x+u(x,y),y+v(x,y)). Here the spatial at operator may be of help (chapter "Operators, Functions, and Constants" in the documentation).
Best Regards
Bettina Schieche