View Issue Details
| ID | Project | Category | View Status | Date Submitted | Last Update |
|---|---|---|---|---|---|
| 0001025 | OpenFOAM | Bug | public | 2013-09-24 11:14 | 2013-09-24 14:29 |
| Reporter | nogenmyr | Assigned To | |||
| Priority | normal | Severity | minor | Reproducibility | always |
| Status | resolved | Resolution | fixed | ||
| Platform | Linux | OS | CentOS | OS Version | 6 |
| Summary | 0001025: Temperature derivative in chemistryModel::derivatives | ||||
| Description | The temperature's temporal derivative is evaluated in chemistryModel::derivatives. For this purpose, the mixtures heat capacity is determined as a sum of components cps in a for-loop. At the end of the for-loop (line 368 in chemistryModel.C) the variable "cp" has the unit J/(kg*K) and seems numerically correct when printed to stdout (1009 for air). Then, just after the loop, cp is =/ mw, giving it the strange unit J/(kg*K) / (kg/kmol) = J*kmol/(kg*kg*K). Next the temperature derivative is calculated as dT = sum(hi*dcdt[i])/(rho*cp). This latter expression would be correct if the unit of cp was left as J/(kg*K). Hence it appears that the line "cp /= mw;" should be removed. | ||||
| Steps To Reproduce | Add the two print lines in chemistryModel.C cp /= mw; Info << "cp " << cp << endl; Info << "mw " << mw << endl; scalar dT = 0.0; compile and run for instance the counterFlowFlame reactingFoam tutorial. The printed cp for the initial air composition is 34.9909. Mean molecular weight is correct. cp for air would either be 1009 J/(kg*K) or 29099 J/(kmol*K). | ||||
| Tags | No tags attached. | ||||
| Date Modified | Username | Field | Change |
|---|---|---|---|
| 2013-09-24 11:14 | nogenmyr | New Issue | |
| 2013-09-24 14:28 |
|
Assigned To | => user21 |
| 2013-09-24 14:28 |
|
Status | new => assigned |
| 2013-09-24 14:29 |
|
Note Added: 0002514 | |
| 2013-09-24 14:29 |
|
Status | assigned => resolved |
| 2013-09-24 14:29 |
|
Resolution | open => fixed |
