#
Properties

- Wrapper around the fixed condition to set the static pressure from a definition of the total pressure
- Applicable to the pressure field

#
Usage

The condition sets the static pressure at the patch \( p_p \) based on a specification of the total pressure, \( p_0 \). The mode of operation is determined via the input entries and the dimensions of the convective flux, phi ( \( \phi \)).

##
Subsonic incompressible

Patch pressure described by subtracting the dynamic pressure from the total pressure, where the flux has dimensions of \( m^3/s \).

\[
p_p = p_0 - \frac{1}{2}\mag{\u}^2
\]

Field file entries:

<patchName>
{
type totalPressure;
rho none;
p0 uniform 0;
value uniform 0;
// Optional entries
U U;
phi phi;
}

##
Subsonic compressible

Patch pressure described by subtracting the dynamic pressure from the total pressure, where the flux has dimensions of \( kg/s \).

\[
p_p = p_0 - \frac{1}{2}\rho\mag{\u}^2
\]

Field file entries:

<patchName>
{
type totalPressure;
p0 uniform 100000;
value uniform 100000;
// Optional entries
U U;
phi phi;
rho rho;
}

##
Transonic compressible

Ratio of specific heats, \( \gamma = C_p/C_v \) equal to 1.

\[
p_p = \frac{p_0}{1 + \frac{1}{2} \psi \mag{\u}^2}
\]

Field file entries:

<patchName>
{
type totalPressure;
psi psi;
p0 uniform 100000;
value uniform 100000;
// Optional entries
U U;
}

##
Supersonic compressible

Ratio of specific heats, \( \gamma = C_p/C_v \) greater than 1.

\[
p_p = \frac{p_0}{\left(1 + \frac{\gamma - 1}{2 \gamma} \psi \mag{\u}^2\right)^{\frac{\gamma}{\gamma - 1}}}
\]

Field file entries:

<patchName>
{
type totalPressure;
psi psi;
gamma 1.4;
p0 uniform 100000;
value uniform 100000;
// Optional entries
U U;
}

#
Further information

Source code:

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