Cavitation shares the same physical process as boiling which is described in the Multiphase module. Fundamentally, both cavitation and boiling are the evaporation and condensation process between liquid and vapor phases. However, the mechanisms that trigger the phase changes are different. Cavitation is predominately caused by mechanical effects which are the sharp pressure changes in fluid systems. Boiling is due to thermal effects that raise the vaporization pressure of a liquid above its local ambient pressure to cause the phase change from liquid to vapor. Therefore, cavitation is generally treated separately from the thermal phase changes as the cavitation process is too rapid to assume thermal equilibrium at the liquid-vapor interface. In many standard cavitation models, the mass transfer is treated as driven purely by liquid-vapor pressure differences. However, thermal effects are included by allowing the phase densities and the saturation vapor pressure as the function of temperature.

In Creo Flow Analysis, a cavitating flow is a liquid-gas mixture whose density varies with the vapor content generated from cavitation, and the other gaseous components existing in a fluid such as noncondensable gases, dissolved gases and so on. The scalar transport equations are solved for the mixture velocity, pressure, temperature (if thermal effect is included), turbulence, and other physical quantities such as noncondensable gas and dissolved gas. With the occurrence of cavitation, an additional equation for vapor must also be solved to determine how much vapor is generated and transported within the fluid mixture. The modeling theory and cavitation models available in Creo Flow Analysis are described in this section. They consist of the following: