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fsi.flexible beam.
Posted Aug 10, 2014, 1:13 p.m. EDT Version 4.3a 1 Reply
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.. I’m trying to simulate a flexible plate oscillating behind a cylinder with no external load applied on the plate, using COMSOL. I tried to start with one of COMSOL’s examples similar to this work, which is “Vibrating Beam in Fluid Flow (oscillating FSI)”. In this example a beam behind a cylinder subjected to a cyclic point load at the end of the beam was oscillating. The Young Modulus of the beam was 5.6e6.
As a first step toward my own study, I removed the point load and the solution successfully converged. Next, I had to decrease the Young Modulus to match my problem. However, by decreasing the young modulus down to 5.6e4, the solution diverges. I think the reason for that is the generation of inverted mesh. Is that true? How can I sort out this issue and get a convergent solution?
As a first step toward my own study, I removed the point load and the solution successfully converged. Next, I had to decrease the Young Modulus to match my problem. However, by decreasing the young modulus down to 5.6e4, the solution diverges. I think the reason for that is the generation of inverted mesh. Is that true? How can I sort out this issue and get a convergent solution?
1 Reply Last Post Aug 11, 2014, 10:55 a.m. EDT
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Posted:
1 decade ago
Hi Tom,
There could be several reasons for the solution divergence. The lower modulus leads to a softer beam that will deform more. That could be causing mesh inversion as you noted. If that is the problem you should see where the mesh is failing and apply some mesh displacements or constraints to “guide” the mesh deformation. The softer beam also leads to a stronger degree of FSI coupling. In that case using a fully coupled solver helps.
Nagi Elabbasi
Veryst Engineering
There could be several reasons for the solution divergence. The lower modulus leads to a softer beam that will deform more. That could be causing mesh inversion as you noted. If that is the problem you should see where the mesh is failing and apply some mesh displacements or constraints to “guide” the mesh deformation. The softer beam also leads to a stronger degree of FSI coupling. In that case using a fully coupled solver helps.
Nagi Elabbasi
Veryst Engineering