Research On The Shapes Of Supercavity Based On Panel Method Of Singularity

The traveling drag can be greatly reduced by supercavitation reduction- drag technology which can break through the traditional speed barrier. The main principle of its reduction drag is using a layer gas to make the moving body and the liquid isolated and reducing humid area of the body so that the considerable viscous forces can be avoided. The research on the shape of supercavitation is an important portion which affects the research later. The theoretical studies of cavitation in the past primarily utilize the potential flow theory and made a good effect to the fluid dynamics. The slender body theory and the boundary element method are modern computing method to the design of supercavitation vehicles. The supercavitation shape research is just done using the panel method of singularity based on the potential flow theory in this paper. The main contents are as following:Firstly, the pilot study is done on the supercavitation shape which includes: the approximate-analytical solution to the supercavitation shape is achieved using the slender body theory and compared with a series of classical experience formulas; projectile experiments is introduced, the aim of which is to know the developing mechanism of supercavitation, observe the developing process and the real shape, and the influencing factor on the shape. At the same time, the relation curve about the cavitation number and the zero dimension cavitation size is achieved; The aim of pilot study is to provide the numerical method with reference.Secondly, the basic theory of panel method based on the velocity potential is introduced. The research is done including the foundation of governing equation, the research on model of tail, the definition of boundary condition, the dispersion of equation, the iteration process and the solutions of all kinds of dynamics parameters.Thirdly, math modeling, the dispersion of equation, the selection of boundary condition and the iteration are done to the specific model .In which, the pressure recovery model and the Riabouchinski wall model are used. It is found that it is ideal to calculate partial cavitation with pressure recovery model and to the supercavitation Riabouchinski wall model is better, the result is close to the experience formulas. It is proved that the panel model is feasible to calculate the cavitation shape and cavitaton number, the simplicity and validity is significant to solve the engineering problems.Finally, the research direction is proposed to the need of theory and engineering.