View Issue Details
| ID | Project | Category | View Status | Date Submitted | Last Update |
|---|---|---|---|---|---|
| 0004172 | OpenFOAM | Feature | public | 2024-11-06 16:41 | 2024-11-07 16:20 |
| Reporter | Luca Cornolti | Assigned To | will | ||
| Priority | normal | Severity | minor | Reproducibility | always |
| Status | resolved | Resolution | fixed | ||
| Product Version | 12 | ||||
| Fixed in Version | dev | ||||
| Summary | 0004172: Definition of mass flux in semiPermeableBaffleMassFractionFvPatchScalarField.C | ||||
| Description | In the Foam::semiPermeableBaffleMassFractionFvPatchScalarField boundary condition, which models the mass diffusion through a semi permeable membrane, the flux is computed as a series of 3 resistances: the diffusion resistance of the cells on the two sides of the patch and the convective term provided by the user. patch().magSf() /(1/c_ + k/alphaEffDeltap + nbrK/nbrAlphaEffDeltap) *(k*Yc - nbrK*nbrYc); Currently, alphaEffDeltap and nbrAlphaEffDeltap are defined from the thermal diffusivity "kappaEff/thermo().Cp()". This implementation is ok if the Lewis number is one, but in general is potentially not consistent with the diffusion term in the species transport equation thermophysicalTransport->divj(Yi). Probably, "kappaEff/thermo().Cp()" should be replaced with DEff to avoid this inconsistency. | ||||
| Tags | No tags attached. | ||||
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These boundary conditions predate DEff and solvers with anything other than a hard-coded unity Lewis assumption. So, perhaps this deficiency is not surprising. > Probably, "kappaEff/thermo().Cp()" should be replaced with DEff to avoid this inconsistency. Whilst this is true, the substantially more complex aspect of this is the corresponding source terms applied to the energy equation. These prevent temperature anomalies being created as a result of the differential species transport. Whilst this was a few hours work, this code needed updating so I'm content with calling this maintenance. The only other options were to remove the conditions or start peppering them with "This only works for unity Lewis" errors. Fixed in dev here: https://github.com/OpenFOAM/OpenFOAM-dev/commit/4d52188c942fc28fada37b5cfe1544bd752bff64 |
| Date Modified | Username | Field | Change |
|---|---|---|---|
| 2024-11-06 16:41 | Luca Cornolti | New Issue | |
| 2024-11-07 16:20 | will | Assigned To | => will |
| 2024-11-07 16:20 | will | Status | new => resolved |
| 2024-11-07 16:20 | will | Resolution | open => fixed |
| 2024-11-07 16:20 | will | Fixed in Version | => dev |
| 2024-11-07 16:20 | will | Note Added: 0013456 | |
| 2024-11-07 16:20 | will | Note Edited: 0013456 |
