Numerical Study Of Supercavitation Around The Submarine Vehicle

The pressures around the objects fall below the saturated vapor pressure at the temperature when the water flows around them. The process of rupturing the liquid by a decrease of pressure at constant temperature is called cavitation. The generation and disappearance of cavity result in important mechanical effects along with the cavity. However, it is very important to decrease the drag force for the submarine vehicle. The nonlinear relation was caused by cavitations which make it too difficult to achieve its analytic solution.A rational relationship of mass transport between water and vapor was concluded on the basis of Rayleigh-Plesset equation. The finite volume method is employed to solve the Navier-Stokes equations and the k , ε equations. For the anisotropy of the multiphase flows, it was hard to find an exact turbulence model. In the cavity zone, turbulence viscosity ratio was over-predicted in standard k-e turbulence model. So an evaluation turbulence model was proposed. In fully cavity zone and pure water zone, the model was in consistent with the standard k-e turbulence model. The turbulent viscosity coefficient in mixing zone was revised in the model. The result by adopted method is in good accord with the experiment data. A simulation of submarine vehicle shows that supercavitation has the good performance in drag reduction. Cavitation number is affected by several variables, each of them affects the flow field differently, and it is necessary to study the influence by each of them. On the other hand, the geometry of vehicle also plays an important role in cavitation multiphase flow. Three kinds of cavitor was simulated in the paper, the result shows that the disk cavitor cause the largest cavity and drag coefficient and the other way round , the cone cavitor cause the smallest cavity and drag coefficient. The simulation result indicated that the length of vehicle was unimportant compared with the cavitor both in cavity zone and drag efficient on the status of supercavitation.