View Issue Details
| ID | Project | Category | View Status | Date Submitted | Last Update |
|---|---|---|---|---|---|
| 0000424 | OpenFOAM | Bug | public | 2012-02-16 12:52 | 2012-02-16 13:56 |
| Reporter | makaveli_lcf | Assigned To | henry | ||
| Priority | immediate | Severity | block | Reproducibility | always |
| Status | closed | Resolution | fixed | ||
| Platform | Linux | OS | Ubuntu | OS Version | 10.04 |
| Summary | 0000424: Courant number is ~4 times higher if compare to OF v1.6 / v1.7.x | ||||
| Description | For different test cases with 3D unstructured industrial grids I get Co number increase ~4 times at the transient simulations start / run. Exactly the same case settings are used. Sudden Co jump results in simulation crash due to divergence of the numerical solution. The only solution to continue simulation is reducing time-step 4 times, thereby simulation time increases 4 times. I consider this issue as critical because Co number estimation should be some thing unified independently from OpenFOAM release! | ||||
| Tags | No tags attached. | ||||
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The method for calculating the Courant number has been changed since version 1.7.x to be better represent the stability requirement of collocated meshes. In general the change hase resulted in slightly lower values. A change in the method to calculate the Courant number does not in itself change the stability of the algorithm or lead to divergence as it is not used in the algorithm; only to set the time-step. If you have a case which behaved differently for the same fixed time-step between different versions of OpenFOAM the issue does not relate to a change in the way in which the Courant number is calculated. |
| Date Modified | Username | Field | Change |
|---|---|---|---|
| 2012-02-16 12:52 | makaveli_lcf | New Issue | |
| 2012-02-16 13:56 | henry | Note Added: 0001039 | |
| 2012-02-16 13:56 | henry | Status | new => closed |
| 2012-02-16 13:56 | henry | Assigned To | => henry |
| 2012-02-16 13:56 | henry | Resolution | open => fixed |
