Flow Characteristics Numerical Study Of The Solid Rocket Pulse Engine

Trajectory-Correction-Projectile is a kind of accurate striking projectile, and its flight position can be controlled via correction implement mechanism. With the development of technology in solid rockets, solid rocket pulse engine, conducting as a thrust vector control device and with its unique advantages that is incomparable, can reach the requirements for trajectory-adjusting and fabricating technics. Compared with other solid rocket engine, the nozzle of the solid rocket pulse has sharp curvature, which results in a complicated gas flow field, and without a heat-shield, which causes overheating in the structure of nozzle and nozzle pedestal. These will cause a decrease in mechanical properties.The main points of the present paper are as follows:(1) Numerical simulation of flow fluidIn this section, a three-dimension physics model and a mathematical model of nozzle flow field are established to calculate the three-dimension flow field, respectively in steady-flow and unsteady-flow. Steady-flow simulation, using the condition of constant total-pressure, analyzes the distribution of flow parameters and the origin rules and development rules of secondary flow in the nozzle. Comparing the results from RNG k -εturbulence model with that from Omega turbulence model can reach the conclusion that the later model, Omega turbulence model, is more suitable. Unsteady-state flow simulation, based on steady-state flow simulation and using experiment total-pressure condition, serves as a pavement for fluid-solid coupled hear interchange simulation.(2) Thermal-coupled numerical simulationIn this section, a three-dimension physics model and mathematic model of nozzle structure are developed to numerically calculate the transient thermal-coupled of the engine in 30 ms. The analysis in this section are focused on the distribution of temperature in nozzle and nozzle pedestal, and the influence of radiation-heat transferring and turbulence model on temperature, and the effects of gas-erosion on ablation. The simulation results indicate that the vortex of the gas flow accounts for the major cause of the high temperature in the surface, and the erosion increases the ablation in the high temperature region of the surface.(3) Thermal-stress numerical simulationIn this section, thermal-stress calculation is based on the critical gradient of temperature load distribution, and the distribution of equivalent stress in nozzle and nozzle pedestal are analyzed. The conclusions of this paper can serve as references regarding optimizing design and heat-shield design of engine.