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- - **Modifying density update in fireFoam**
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Modifying density update in fireFoamHi All,
I am trying to substitute the density calcultaion that OpenFoam uses in fireFoam with my own density calculation model. Since I am a newbie in OF and a newbie in C++ also, I haven't completely understood, how the functionalities and the dependencies are in OF-fireFoam. :confused:. For example, I am even confused what rho = thermo.rho() exactly means, what exactly happens there and where the thermo class is located at... So my questions are: (1) can the density calculation be easily swaped with a different model? (2) where is the thermo class located? (3) does anyone know how the density update works in OF? Is it based on the recursive beta PDF integration and where are the actual calculations happening? Any help is greatly appreciated, Andreas |

Hi,
rho = thermo.rho() returns the density field. Have a look at basicThermo.C, basicPsiThermo.C or basicRhoThermo.C About (1), depends what you want to do. But most of the time, you have to rewrite the entire thermo library About(2) src/thermophsyicalModels About (3) have a look at the classes above. Regards, Christian |

1 Attachment(s)
Hallo Christian,
I am still puzzled how the density update works for the case of the fireFoam solver. The presentation attached states that the density calculation is based on the recursive beta integration in fireFoam. So far, I have not been able to locate where this is happening. When I start from the main file of the fireFoam solver (fireFoam.C), I find that: And I will end up looking at “basicPsiThermo.H”, which defines the “thermo” class called in “fireFoam.C”. In the lines 98-101, I find that: Code:
`00097 //- Density [kg/m^3] - uses current value of pressure` I would really appreciate if you could give me some hints on how to understand the density update process. Gruß, Andreas |

Hi,
p_ -> from the solver. In the solver, the p field is a pointer, psi-> equation of state. Regards, Christian |

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