火箭喷焰微波衰减特征的理论研究

Theoretical study on attenuation characteristics of microwave in rocket exhaust plume

目前火箭喷焰微波衰减的计算是基于等离子体理论，根据微波衰减常数的实验测量结果，必须将理论公式中的电子浓度估计到一个很高的值。然而，这一很高的电子浓度值与火箭喷焰的化学反应动力学理论结果不相符。为了解决这一矛盾，在尘埃等离子体理论基础上，导出了弱电离尘埃等离子体的微波衰减常数和相位常数计算公式。将固体火箭喷焰的有关参数重新代入计算，给出的微波衰减常数比等离子体理论给出的结果大1～3个量级。所得结果与微波衰减的实验观测相符。

At present, microwave attenuation in rocket exhaust plume can be calculated based on plasma theory. According to experimental measurement results of microwave attenuation coustant,electron density in the theoretical formula must be desired to be a higher value,but this value isn＇t consistent with that of chemical reaction dynamics theory for rocket exhaust plume. In order to solve the problem,the calculation formula of microwave attenuation constant and phase constant of weakly ionized dusty plasma was deduced based on dusty plasma theory. The relevant parameters of rocket exhaust plume were substituted into the formula,the calculation results agree well with actual measurement results of microwave attenuation,and microwave attenuation constant is 1-3 magnitude bigger than that of dusty plasma theory.