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kylehudson
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ANSYS Help: Simple Modal Analysis of Plate
I am modeling a plate (36"x3"x.25") in ANSYS. When I construct a line out of two keypoints and give the line a rectangular section, the analysis works and I can output modal displacements just fine. With these modal displacements I can plot the mode shapes outside of ANSYS. I can also see the mode shapes animated inside ANSYS.
However, if I try to construct the same plate using the same section out of 4 key points (2 long lines and one very short one in between) I get bad results. When I output my modal displacements for the each mode I see a huge spike at the in-between key points.
Its like there is a discontinuity between the key points or lines in the middle, even though all my lines' section properties are the same. When I plot my node numbers, I see that ANSYS has moved my node at the in-between line to the last point of the next line. Therefore, that node's displacement is huge relative to where its location is supposed to be.
(I.e. ANSYS has taken node 65, which is at the middle of my in-between line and moved it to after node 315, the last node of my line. Node 65 now sees a displacement that node 316 would, not node 65)
I am using beam189 elements with an element size of .4mm.
ANY HELP WOULD BE APPRECIATED
I am modeling a plate (36"x3"x.25") in ANSYS. When I construct a line out of two keypoints and give the line a rectangular section, the analysis works and I can output modal displacements just fine. With these modal displacements I can plot the mode shapes outside of ANSYS. I can also see the mode shapes animated inside ANSYS.
However, if I try to construct the same plate using the same section out of 4 key points (2 long lines and one very short one in between) I get bad results. When I output my modal displacements for the each mode I see a huge spike at the in-between key points.
Its like there is a discontinuity between the key points or lines in the middle, even though all my lines' section properties are the same. When I plot my node numbers, I see that ANSYS has moved my node at the in-between line to the last point of the next line. Therefore, that node's displacement is huge relative to where its location is supposed to be.
(I.e. ANSYS has taken node 65, which is at the middle of my in-between line and moved it to after node 315, the last node of my line. Node 65 now sees a displacement that node 316 would, not node 65)
I am using beam189 elements with an element size of .4mm.
ANY HELP WOULD BE APPRECIATED
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