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Bending a fiber.

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I am having trouble simulating the bend of a fiber into a circular arc. I am trying two approaches:

A) Using the Solid Mechanics physics to apply a body load onto a silica fiber in the direction of a steel cylinder.

This approach has given me odd results: fiber not bending, fiber greatly expanding in volume (at least in the plot), and the fiber being displaced INTO the steel cylinder.

B) Using the Beam physics to apply an acceleration toward a steel cylinder

This approach computes just fine, but both the stress and displacement plots come up with errors.

Failed to evaluate variable.
-Variable: Y
Failed to evaluate expression.
-Expression: Y

Failed to evaluate variable.
-Variable: solid.mises
Failed to evaluate expression.
-Expression: solid.mises

If anyone could help me get either of these simulations working, it would be a great help.


1 Reply Last Post 30.07.2012, 11:49 GMT-4
Nagi Elabbasi Facebook Reality Labs

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Posted: 1 decade ago 30.07.2012, 11:49 GMT-4
Hi Matthew,

The fiber appearing to expand in volume may be a post-processing issue. Make sure you do not scale displacements. Also make sure you include geometric nonlinearity in the solver. Using beam equations you should be able to apply a bending moment at one end of the fiber (that is fixed at the other) and it will deform into a circular arc with curvature proportional to the applied moment.

Nagi Elabbasi
Veryst Engineering
Hi Matthew, The fiber appearing to expand in volume may be a post-processing issue. Make sure you do not scale displacements. Also make sure you include geometric nonlinearity in the solver. Using beam equations you should be able to apply a bending moment at one end of the fiber (that is fixed at the other) and it will deform into a circular arc with curvature proportional to the applied moment. Nagi Elabbasi Veryst Engineering

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