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Long Thin Beam - Convergence Problem

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Dear all,
I'm pretty new in Comsol, and I'm now facing a tedious problem with a really easy simulation, so I'm sure that someone here can give me some smart advice.

In 2D Solid Mechanics field and Frequency Domain Analysis, I would like to plot the frequency response function of a beam with a force applied on it. It will help me for a way more complicated system.

I have created a rectangle, 0.5m long and 0.001m thick (in the off-plane direction I consider a dimension of 0.01m). The material is aluminium. I clamp both ends and I introduce an Isotropic Loss Factor for the material.
About the force application on the structure, I have some doubts: I have tried both the Point Load (creating a Point in geometry at a certain length of the beam) and the Boundary Load (I have "sliced" the original rectangle in 3 parts: one of them is 5mm long and I apply the force on one of its sides), but the simulation was aborted in both cases.

I have created a user-controlled mesh with a Mapped geometry using 4 elements along the thickness.

I set the frequency range, and if I now start the simulation it fails after one (or few, playing a bit with the parameters) steps, saying that the relative error is greater than the relative tolerance.

Due to the fact that I'm not an expert with this software, I don't understand if I make some mistake with the procedure/the parameters, or if the problem is more related to the particular geometry I'm tackling, or something else.

I'd really appreciate if someone has some suggestion to provide.
With my best regards,
Edoardo

0 Replies Last Post 2015年10月16日 GMT-4 10:43
COMSOL Moderator

Hello Edoardo Belloni

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