Abstract: On the basis of the characteristics and working process of HAP tri-propellant in torpedo rotary combustion chamber, mathematical models for the turbulent two-phase flow and combustion process were established. The initial and boundary conditions were investigated and set accordingly. Numerical simulations were conducted by using the software FLUENT, and the distributions of flow fields within the combustion chamber under different regimes were obtained. The results indicate that the turbulent flow and blending process is enhanced and the reverse flow moves to center and head areas. The fuel vaporization, blending, diffusion and heat transfer during combustion process as well as combustion are enhanced, and combustion process becomes much more uniform and steady. Therefore, the combustion efficiency can be improved and the size of rotary combustion chamber could be smaller than the fixed combustion chamber.