Numerical investigation of transient sheet/cloud cavitating flow around hydrofoil via incompressible and compressible methods

This study compares two numerical analyses of dynamic cavitating flow from a sheet to a cloud considering both incompressible and compressibility models. In the incompressible simulation, the densities of the liquid and vapor remain constant. However, in the compressible case, the Tait equation of state and the ideal gas equation of state are used to characterize the two density attributes. The results demonstrate that the development of cavitation morphology can be effectively replicated using two methods. The predicted frequency of cloud shedding utilizing the compressible methodology is lower than that of the incompressible technique, exhibiting a disparity of around 31.40 %. However, the time-averaged force coefficients predicted by the two techniques are highly similar. The research conducted on the destabilization of sheet bubbles indicates that the condensation shock that is triggered by the inertia exerts a dominant influence on the local flow field. The backward flow beneath the sheet bubble is not the cause, but rather the outcome. Pressure pulses generated propagate in all directions as the cloud bubble above the hydrofoil surface collapses. Thus, pressure surges can have a substantial impact on hydraulic performance.