Thermophysical properties are specified in user-selectable packages that
describe collections of models, based on either compressibility
(\(\psi\), psi
) or density (\(\rho\), rho
).
The system starts with the specieβthe most basic entity that describes information such as the specie name, molecular weight and gas constant. This is extended by additional models that return thermophysical properties as functions of pressure and temperature.
Requirements vary according to the solver application, e.g. for single phase, multiphase, compressibility- or density-based, chemical reactions etc.
Single phase systemsπ
Thermophysical properties for single phase calculations are specified in the file:
$FOAM_CASE/constant/thermophysicalProperties
The main thermoType
dictionary entry defines the set of models used to
describe the system, comprising the entries:
thermoType
{
type <thermophysical-model>;
mixture <mixture-model>;
transport <transport-model>;
thermo <thermodynamics-model>;
equationOfState <equation-of-state-model>;
specie <specie-model>;
energy <energy-model>;
}
Here, the type
entry sets the top-level thermophysical model type, e.g.
-
hePsiThermo
: compressibility-based (source code) -
heRhoThermo
: density-based (source code) -
heheuPsiThermo
: compressibility-based with extensions for mixture is burnt/unburnt systems (source code) -
heSolidThermo
: solid-based (source code)
The he
prefix signifies the energy variable that may be based on either
enthalpy (h
) or internal energy (e
).
The mixture
type depends on the solver application; mixtures that can be
approximated by a single component are defined using the pureMixture
type:
mixture pureMixture;
All properties are then defined in a mixture
sub-dictionary taking the form:
mixture
{
specie
{
...
}
equationOfState
{
...
}
thermodynamics
{
...
}
transport
{
...
}
}
Each of the mixture
entries are described in the following sections:
Available options for the energy
entry include:
- absoluteEnthalpy
- absoluteInternalEnergy
- sensibleEnthalpy
- sensibleInternalEnergy
Multi-component mixturesπ
Both reacting and non-reacting mixtures are supported by some applications. The required inputs typically follow the pattern described above:
Multiphase systemsπ
Each phase is described separately for multiphase systems, using file names with the convention:
$FOAM_CASE/constant/thermophysicalProperties.<phase>
Further informationπ
Source code: