View Issue Details
| ID | Project | Category | View Status | Date Submitted | Last Update |
|---|---|---|---|---|---|
| 0003395 | OpenFOAM | Patch | public | 2019-11-24 11:20 | 2019-11-24 15:04 |
| Reporter | handrake0724 | Assigned To | henry | ||
| Priority | normal | Severity | minor | Reproducibility | have not tried |
| Status | closed | Resolution | no change required | ||
| Product Version | dev | ||||
| Summary | 0003395: rigidBodyMeshMotion behavior with linear spring with offset | ||||
| Description | current implementation of rigidBodyMeshMotion applies ramp value to gravity and hydrodynamic forces. When it comes to free decay simulation or VIM simulation, configuration is set up with linear springs which have sometimes initial offset from the rest length. In that case, one wants the flows let go while the body does not moved at all until ramp function above zero. but in the current implementation, the body moves due to the restoring force of the spring even if ramp function value is still zero. so, ramp function cannot control restraint force. I am not sure if this behavior is intended or not. in order to apply the ramp effect to restraints also, Just simply introduce conditional such that in rigidBodyMeshMotion.C:291 RBD::rigidBodyMotion::solve ( t.value(), t.deltaTValue(), scalarField(nDoF(), Zero), fx ); modified into if (ramp > 0) { RBD::rigidBodyMotion::solve ( t.value(), t.deltaTValue(), scalarField(nDoF(), Zero), fx ); } what do you think about this modification? | ||||
| Tags | No tags attached. | ||||
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I am confused by this change, why switch on the value of the ramp being > 0? What should happen if ramp is very small rather than 0? If there is a force which should depend on the ramp shouldn't it depend on it in a continuous manner rather than be switched on it being >0? |
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my apologies. I have rechecked my simulation setup and found it does not need any changes to rigidBodyMeshMotion class. I think something went wrong when I tested case and thus modified the code. Sorry again for bothering you. |
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User error. |
| Date Modified | Username | Field | Change |
|---|---|---|---|
| 2019-11-24 11:20 | handrake0724 | New Issue | |
| 2019-11-24 11:49 | henry | Note Added: 0010936 | |
| 2019-11-24 12:45 | handrake0724 | Note Added: 0010937 | |
| 2019-11-24 15:04 | henry | Assigned To | => henry |
| 2019-11-24 15:04 | henry | Status | new => closed |
| 2019-11-24 15:04 | henry | Resolution | open => no change required |
| 2019-11-24 15:04 | henry | Note Added: 0010938 |
