磁化等离子体对圆筒结构内流场特性的影响

摘要

鉴于高温高压火药燃气的等离子体特性,提出一种利用磁化等离子体改善火药燃气气动特性与提升推力的方法.基于FLUENT软件的MHD模块与UDF二次开发功能,采用诱导磁场法对等离子体控制方程进行了求解,数值研究了磁化等离子体对圆筒结构内流场特性的影响.结果表明:外加磁场强度和等离子体电导率是影响流动各向异性的两个主要的因素.外加磁场后,等离子体内感应出的洛伦兹力能够降低壁面的摩擦系数与燃气的湍流强度,从而有效降低摩擦损失和燃气向壁面的传热量,最终提升沿轴线方向的燃气压力.当外加磁场为1T、电导率为5000s/m时,壁面摩擦系数减小了约8.7％.%In view of plasma characteristics of high-temperature and high-pressure propellant gas,a method is presented to improve the aerodynamic characteristics and thrust of propellant gas by use of magnetized plasma.Based on the MHD module of FLUENT software and the secondary development function of UDF,the plasma control equations were solved with magnetic induction method,and the influence of magnetized plasma on the characteristics of flow field in the cylinder structure was numerically studied.The results show that external magnetic field intensity and the electrical conductivity of plasma are the two main factors affecting the flow anisotropy.The Lorentz force induced in the plasma can reduce the friction force of the wall and the turbulence intensity of the gas that will result in the decrease of the friction coefficient and the heat transfer from the gas to the wall effectively.Finally the gas pressure along the axial direction can correspondingly increase.When the applied magnetic field is 1T and the conductivity is 5000s/m,the friction coefficient of the wall decreases about 8.7％.