Moving mesh problem

barsvinicius · August 9, 2013, 05:54

Hello,

I have an OpenFOAM case with a circular cylinder (cross-section) and I want to apply motion to it. I want to simply move it from x1 to x2, only a horizontal motion. The amplitude of my motion is 0.5m and the function parameters are the following:

oscillatingDisplacement
omega = 6rad/s
amplitude = (0.5 0 0)
endTime = 0.3

The problem is that my simulation always crashes at 0.172 seconds and I think this is happening because the cells are too compressed in one point because when I make the mesh coarser it can run for a little bit longer.

I'm a newbie to OpenFOAM, so is there anyone who could have any idea of what's going on and how I can solve it?

Thanks in advance

jhoepken · August 12, 2013, 02:20

Hi barsvinicius,

What solver are you using? Regardless of the solver, I would try to use the moveDynamicMesh tool to test if the mesh motion is the root cause of your problem. Just execute it in your case directory. It solely performs the dynamic mesh steps, no other equations are taken into consideration.

If this does not blow up and the mesh looks fine during the simulation, something else blows up. Remember to run checkMesh after the simulation.

Please attach some more information on your case setup to your next post (solver, mesh dimensions, checkMesh output for time=0, fvS* files, dynamicMeshDict,...)

Jens

August 9, 2013, 05:54	Moving mesh problem	#1
barsvinicius New Member Vinicius Barros Join Date: May 2013 Posts: 1 Rep Power: 0	Hello, I have an OpenFOAM case with a circular cylinder (cross-section) and I want to apply motion to it. I want to simply move it from x1 to x2, only a horizontal motion. The amplitude of my motion is 0.5m and the function parameters are the following: oscillatingDisplacement omega = 6rad/s amplitude = (0.5 0 0) endTime = 0.3 The problem is that my simulation always crashes at 0.172 seconds and I think this is happening because the cells are too compressed in one point because when I make the mesh coarser it can run for a little bit longer. I'm a newbie to OpenFOAM, so is there anyone who could have any idea of what's going on and how I can solve it? Thanks in advance

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August 12, 2013, 02:20		#2
jhoepken Senior Member Jens Höpken Join Date: Apr 2009 Location: Duisburg, Germany Posts: 159 Rep Power: 17	Hi barsvinicius, What solver are you using? Regardless of the solver, I would try to use the moveDynamicMesh tool to test if the mesh motion is the root cause of your problem. Just execute it in your case directory. It solely performs the dynamic mesh steps, no other equations are taken into consideration. If this does not blow up and the mesh looks fine during the simulation, something else blows up. Remember to run checkMesh after the simulation. Please attach some more information on your case setup to your next post (solver, mesh dimensions, checkMesh output for time=0, fvS* files, dynamicMeshDict,...) Jens