CFD Calculation of Axially Symmetric Supercavities

Engineering interest in natural and ventilated cavities about submerged bodies and in turbomachinery has led researchers to study and attempt to model large scale cavitation for decades. Comparatively simple analytical methods have been used widely and successfully to model developed cavitation, since the hydrodynamics of these flows are often dominated by irrotational and rotational inviscid effects. However, a range of more complex physical phenomena are often associated with such cavities, including viscous effects, unsteadiness, mass transfer, threedimensionality and compressibility. Through some of these complicating physics can be accommodated in simpler physical models, the ongoing maturation and increased generality of multiphase Computational Fluid Dynamic (CFD) methods has motivated recent research by a number of groups in the application of these methods for developed cavitation analysis. In this paper the numerical simulation of supercavitating flow was performed. The flow was assumed isothermal and consists of two phases, liquid and its vapor. A transport equation based cavitation model was used for the numerical simulation of the flow field including natural supercavitation. A mass transfer between the phases is treated as a source and sink terms in vapor transport equation. The numerical method is used for different geometries in a wide range of cavitation numbers. The cavity parameters such as cavity length and cavity width were compared with experimental data and agreed very closely.