View Issue Details
ID | Project | Category | View Status | Date Submitted | Last Update |
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0001363 | OpenFOAM | Bug | public | 2014-07-30 08:51 | 2015-04-08 16:21 |
Reporter | Juho | Assigned To | henry | ||
Priority | normal | Severity | feature | Reproducibility | always |
Status | resolved | Resolution | fixed | ||
Summary | 0001363: twoPhaseEulerFoam: Improved treatment of interfacial forces | ||||
Description | At least in dispersed vertical pipe flows, the twoPhaseEulerFoam has a strong tendency to produce volume fraction oscillations in regions where lift, dispersion and wall lubrication forces are strong. See the attached "original.png" for an example. It appears that the issue can be mitigated by including these forces on the cell faces in the pEqn. A version of such implementation is shown in the "Additional Information" field. In the present test case the oscillations were eliminated, as shown in "modified.png" | ||||
Additional Information | An excerpt from the modified pEqn.H: surfaceScalarField WF ( fvc::interpolate(fluid.wallLubricationForce()) & mesh.Sf() ); surfaceScalarField LF ( fvc::interpolate(fluid.liftForce()) & mesh.Sf() ); // Phase-1 pressure flux (e.g. due to particle-particle pressure) surfaceScalarField phiP1 ( "phiP1", fvc::interpolate(rAU1*phase1.turbulence().pPrime()) *fvc::snGrad(alpha1)*mesh.magSf() ); phiP1 += fvc::interpolate(rAU1*fluid.turbulentDispersionForcePrime()) *fvc::snGrad(alpha1)*mesh.magSf() + fvc::interpolate(rAU1)*(WF + LF); phiP1.boundaryField() == 0; // Phase-2 pressure flux (e.g. due to particle-particle pressure) surfaceScalarField phiP2 ( "phiP2", fvc::interpolate(rAU2*phase2.turbulence().pPrime()) *fvc::snGrad(alpha2)*mesh.magSf() ); phiP2 += fvc::interpolate(rAU2*fluid.turbulentDispersionForcePrime()) *fvc::snGrad(alpha2)*mesh.magSf() - fvc::interpolate(rAU2)*(WF + LF); phiP2.boundaryField() == 0; | ||||
Tags | No tags attached. | ||||
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@Juho: Can you please provide an example case, in order to make it easier to diagnose and confirm this? |
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I am working on this at the moment and have what I need. I am investigating this in conjunction with http://www.openfoam.org/mantisbt/view.php?id=1313 as the issues relate. The basic principles are simple but in the case of #1313 a significant rewrite of fvOptions will be required for an elegant implementation. However, the simple interpolation/reconstuction approach proposed will not necessarily conserve the volume integrated force, which for some force models may be important/critical. This is why I have not implemented the approach yet. I am now working on a special interpolation/reconstuction combination which will conserve the integrated force. |
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@Henry: Also seems related to this one: http://www.openfoam.org/mantisbt/view.php?id=1046 |
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@Juho Could u pls provide some info on "why add these forces on pEqn works better than including them on UEqn?". I mean the basic theory. Thanks. |
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I have converted all forces to be face-based in twoPhaseEulerFoam in OpenFOAM-dev which is beneficial for many case but not all. The behavior is VERY sensitive to the lift modelling and the way in which the curl is handled (an alternative is to use a reconstructed velocity which is smoother). These changes are integrated with the other recent developments including partial-elimination to aid convergence of the drag-coupling and an improved ddtCorr. Resolved by commit fcbdfd4e44b4a539bcb3514c5607721a4ec1e052 |
Date Modified | Username | Field | Change |
---|---|---|---|
2014-07-30 08:51 | Juho | New Issue | |
2014-07-30 08:51 | Juho | File Added: original.png | |
2014-07-30 08:51 | Juho | File Added: modified.png | |
2014-12-29 11:27 | wyldckat | Note Added: 0003376 | |
2014-12-29 11:35 | henry | Note Added: 0003380 | |
2014-12-29 14:45 | wyldckat | Note Added: 0003394 | |
2015-02-11 05:04 | sharonyue | Note Added: 0003748 | |
2015-03-24 00:17 | liuhuafei | Issue cloned: 0001608 | |
2015-04-08 16:21 | henry | Note Added: 0004577 | |
2015-04-08 16:21 | henry | Status | new => resolved |
2015-04-08 16:21 | henry | Resolution | open => fixed |
2015-04-08 16:21 | henry | Assigned To | => henry |