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Moving solid domain within a fluid domain

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Objective of my model: An electrostatic probe is removed from an initially static fluid. The speed of probe extraction is varied and the resulting disturbances of the fluid are observed.

So far I have built a deformed geometry and successfully moved the probe. In this simulation, the laminar flow module was disabled. I then ran a second simulation in which I only solved for the laminar flow module while using the result of the previous simulation (the deformed mesh result) for the deformed mesh. That is, under "values of variables not solved for" I used the result of the first simulation. I expected to have results in which the fluid is disturbed by the motion of the probe but the fluid doesn't seem to "see" the motion of the probe. That is, the fluid remains static. I know this result is unphysical. What am I missing? Why can't the fluid see the probe's motion?


1 Reply Last Post May 28, 2017, 8:38 p.m. EDT

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Posted: 7 years ago May 28, 2017, 8:38 p.m. EDT
Updated: 7 years ago May 28, 2017, 8:41 p.m. EDT
Jacob,
Have you coupled the fluid flow to the deformed geometry?
You need to do this by changing the wall boundary condition in the fluid flow physic. In your case, the solid is moving, so you need to define a moving wall having the velocities equal to the moving mesh.
Amin,
Jacob, Have you coupled the fluid flow to the deformed geometry? You need to do this by changing the wall boundary condition in the fluid flow physic. In your case, the solid is moving, so you need to define a moving wall having the velocities equal to the moving mesh. Amin,

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