The calculation formulas for velocity coefficients 2 and 5 for the throat and throat inlet section were deduced from the theoretical research on the velocity coefficients in time - averaged basic equations by use of the unsteady momentum equation and time - averaged value calculation method 摘要运用非恒定的动量方程和时均值计算方法，对脉冲液体射流泵时均值基本方程中的流速系数进行了理论研究，推导出了喉管和喉管进口段流速系数2和5的计算式。
