Study Of Forming Cavity On The Underwater Bodies

A numerical method is developed for solving the process of forming cavity on the moving object in the planar moving mesh when the object moves in the immobile liquid. the Reynolds time-averaged method and k-εdouble equations model are adopted. The moving mesh method is used to eliminate the impossibility of simulating the process of entering and floating up water when the object is immobile. Based on SIMPLE algorithm, the crisscross grid technique and finite-volume method, and the discrimination algebraic equation is solved by used G-S iterative method. Using this method, the planar process of forming cavity is calculated for liquid flowing around the immobile object and object moving in the immobile liquid.The main research is studying the result of using different gas velocity to form cavity when the liquid flow around the immobile object or the object move in the immobile liquid. It's showed that the volume of gas upon the object raises up and flowing velocity of liquid increases with increasing gas velocity. The difference of the cavity shape is discovered when the object float up and enter the liquid. Numerical results are in good agreement with experimental research.As a boundary of reattachment point, it is still useful for improving the quality of gas cavity and the velocity of moving underwater when the cavity appears. And it's also important to control the velocity of floating in a bound. The program of using rocket under water is tough but doable.