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/*!
\page cavit Data setting for the cavitation model
\section cavitation_h_intro Introduction
The cavitation model is based on a homogeneous mixture model, and a sub-model
of the Volume of Fluid model.
The physical properties (density and dynamic viscosity) of the mixture depend
on a resolved void fraction and constant reference properties of the liquid
phase and the gas phase.
The void fraction is given by an advection equation with a
vaporization/condensation source/sink term. This term is modeled by the
Merkle's model. The model also integrates the eddy-viscosity correction of
Reboud.
\section cavit_activ Activation of the model
The module can be activated in \ref cs_user_model in
\ref cs_user_parameters.c as show below:
\snippet cs_user_parameters-base.c enable_cavit
Data structure is defined in \ref vof, \ref vof_mixture_properties and
\ref cavitation.
Cavitation modelling main feature consists in modelling
vaporisation/condensation with Merkle model providing source / sink term for
the void fraction equation.
\section cavit_parameters Cavitation module specific parameters.
When cavitation model is enabled, specific input parameters can be set in
\ref cs_user_parameters in \ref cs_user_parameters.c file as shown below:
\subsection cavit_phprop Homogeneous mixture physical properties
The reference density, in \f$ kg/m^3\f$ , and molecular viscosity, \f$ kg/(m\cdot s)\f$,
of the liquid phase and the gas phase should be set. For instance:
\snippet cs_user_parameters-base.c phprop
Other parameters, specific to cavitation are stored in \ref cs_cavitation_parameters_t
structure. A pointer to this structure should be retrieved as follows:
\snippet cs_user_parameters-base.c cavit_param
\subsection cavit_source Model parameters of the vaporization term (Merkle model)
Merkle's model parameters should be set.
Merkle's model is based on a barotropic law for the density (see \ref cavitation.f90).
In that way, its principal parameter is the saturation pressure of the fluid,
in \f$ kg/(m\cdot s^2)\f$. For instance, the saturation pressure of the water at twenty
celcius degrees is set below:
\snippet cs_user_parameters-base.c presat
Merkle's model also requires a reference length scale and velocity of the flow.
For instance:
\snippet cs_user_parameters-base.c scales_inf
These scales are integral scales. For instance, considering the cavitating
flow across a foil in a duct, the reference velocity should be the bulk
velocity and the reference length scale should be the chord of the foil.
\subsection cavit_turb Interaction with turbulence
The mixture eddy-viscosity correction proposed by Reboud can be accounted for
as shown below:
\snippet cs_user_parameters-base.c reboud_activ
Using an eddy-viscosity model (see \ref turbulence), this option is
recommended and is hence a default setting. Of course, this option has no
effect for second moment closure or large eddy simulations. Note that the
coefficent mcav of the reboud correction (see \ref cavitation.f90) can also
be adjusted in the \ref cs_user_parameters function.
\subsection cavit_numerics Numerical options
Advanced numerical parameters may also be set in this function, if necessary.
The concerned variables are listed in \ref cav_numerics.
*/
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