Numerical simulation of complex flow field for missile launched under-water under gas proof conditions

To research the complex flow field for missile launched under water under gas proof condition, the multi-phase mixing model was used to simulate the coupled flow, heat transfer and phase changing process between combustion gas, liquid water and water steam. The dynamic mesh method was used to update the flow field following with the missile movement. The calculated results indicate that the pressure at the nozzle exit, which is influenced by the coupled flow, experienced different status, such as pressure peak value, second peak value, step increase, pressure vibration and so on. Furthermore, the developing process of the gas cavity and the temperature variation on the missile surface were discovered during the calculating process.