Numerical simulation of underwater explosion bubble with different boundaries

The FEM Software MSC.Dytran was used to simulate the underwater explosion bubble pulses in different boundaries.Some important problems were discussed,such as the modeling of charge,the size of element,EOS(equations of state) and hydrostatic pressure field initialization.Simulations were done on the underwater explosion bubble in infinite water,the bubble below the free surface and horizontal rigid plane and the bubble close to vertical rigid plane.The radii of bubble,the change of its figures,the pressure of bubble pulse and the velocity distributing in water were studied,and then the boundary was found to have great effect on the bubble profile,and the rigid plane could increase the pulse pressure,but the free surface not.The results of simulation of bubble pulse are proved to agree well with those of the academic formula,empirical equation and test.