Dynamic Analysis Of Rocket Jet Flow

At present,multi-rocket launch rocket system(Multiple Launch Rocket System)is developing towards to high precision,long range and high mobility.The jet flow of rocket is one of the main factors that affect the launch vibration and shooting accuracy of MLRS.The numerical calculation of rocket jet flow can provide support for the analysis of the influence of jet flow on the launch dynamics and the design of MLRS.This paper focuses on the engineering calculation method of rocket gas jet and the computational fluid dynamics method,and the dynamic process of the rocket’s gas jet at different loading positions and the dynamic response of the rocket under the action of the gas jet are analyzed.The main work is as follows:1)Based on the theory of isentropic flow,the engineering calculation model of free jet is adopted.Then,the Boolean operation method is used to judge the effective area of rocket jet flow at different loading positions,and the jet pressure distribution is integrated in this area.The impact force characteristic curve of rocket jet flow is obtained,and the fast calculation of rocket jet flow is realized.2)The three-dimensional unsteady simulation model of rocket jet flow is established.The dynamic process of the rocket jet flow at three different loading positions is numerically calculated by using the multi block mesh generation and dynamic mesh method.The law of the flow field of the jet flow and the load distribution on the upwind face of the directional device are obtained.The results shows that the impact force of the rocket jet flow is affected by the effective area and the pressure of jet flow.3)The impact force of the simulated jet flow is regarded as the external force of the system.The dynamic response of MLRS under three different firing states is calculated and analyzed by using the visual simulation and design software of transfer matrix method for multi-body systems(MSTMM Sim).The results show that the impact force of the jet flow of the rocket at different loading position affects the dynamic response of the directional tube,and then the firing accuracy.These provides theoretical support for the precise analysis of the launch dynamics of MLRS and the design of the launch device...