本文在讨论了各种测量气流速度的方法,特别是Miller的放电法基础上,提出了一种测量低密度流场气流速度和运动激波马赫数的改进方法。本方法采用双曝光技术,有助于提高测量精度;在结构上和电路上的改进,克服了低密度流场中漏电问题。该方法适用于气流速度1200m/s以上,密度约0.05kg/cm~3的高速瞬态流场中的气流速度和运动激波马赫数的测量。 In this paper, we discuss various methods for measuring the gas velocity, especially Miller’s discharge method, and propose an improved method to measure the gas velocity and the shock wave Mach number in the low density flow field. The method uses double exposure technology, which helps to improve the measurement accuracy. The improvement in structure and circuit overcomes the leakage problem in the low-density flow field. The method is suitable for the measurement of the gas flow velocity and the shock wave Mach number in the high-speed transient flow field with the airflow velocity of 1200 m / s and the density of about 0.05 kg / cm ~ 3.