Analysis Of The Gas Flow Field Of Ballistic Missile Launch Position And Personnel Safety

Overpressure, high temperature, high speed, vibration and other extreme environment ofmissile combustion gas jet has a serious impact on the safety of the surrounding and missilelauncher. In order to ensure personnel safety in using missile and improve the survival abilityof missile weapon system, we analyze the dynamic characteristic of the gas flow field withnumerical simulation method. The paper uses a typical ballistic missile as the research object,analyzing the complex gas free flow of missile engine and the characteristics of the impact onvertical flat, simulating two-dimensional flow field of the gas emission position withnumerical simulation method, obtaining the numerical solution of field variable withoverpressure, temperature, composition, etc, under different surface distance below themissile firing height, analyzing the environmental safety of launching position and giving thepersonnel tolerance range of security with handing the numerical solution.First of all, in order to simulate the dynamic gas flow field when missile is launched, themissile engine nozzle flow field of the pure gas phase flow physical model is established byusing GAMBIT software. According to the size of the flow field calculation area, and after acomprehensive analysis of guaranteeing accuracy and reducing the amount of computation,etc, we take a reasonable partition for the entire calculation area and generate high-qualitynetwork, set up missile rigid motion boundaries in order to achieve the functionality ofdynamic grid.Secondly, with CFD in FLUENT software, the missile launch dynamic gas flow field issimulated through the realizable k-e turbulence model, obtaining wave structure of underexpanded supersonic gas jet, giving the cloud picture of overpressure, Maher number,temperature, composition and other variables, and the time history curve of the field variablesat different distances from the ground1.7m.Finally, combining with the results of numerical simulation and the proven evaluation standards of personnel safety, summarizing the evaluation standards of damage of fieldvariables of gas jet on human body, the paper gives the safe distance of field variables aroundthe surface of the launch center under different missile ignition height and designates the saferange. The results can be used as a theoretical basis for the design of gas protective equipmentand the safe use of missiles.