后效期火药气体流空过程数值模拟

Numerical Simulation of Propellant Gas Emptying Process in After-Effect Period

后效期火药气体流空规律与火药气体作用系数历来是各国兵器研究的重要内容。现有的火药气体作用系数的计算方法多是在准定常假设下得到的理论或经验关系式,适应面较窄,误差普遍偏高。本文采用AUSM+格式和双时间步法,对65式37mm高炮(无膛口装置和带不同锥形消焰器)共5个算例的火药气体流空过程进行了数值模拟,根据数值结果计算了火药气体作用系数,与实验值相比,误差能控制在6%以内,符合较好。为进一步研究复杂条件下的后效期流空规律打下了基础。

The investigations on the law of propellant gas emptying and its active coefficient are very important content in armament research and development. The existing theoretical or empirical formula of propellant gas active coefficient was based on the quasi-steady assumption. Their adaptability is limited and the error is generally large. Five cases for propellant gas emptying of 65-37mm guns were simulated numerically by use of AUSM＋scheme and dual-time method. The calculated active coefficients of propellant gas based on these numerical results were in good agreement with the experimental results. Compared with the experimental data, the error is no more than 6 %. This research can provide the base for the further investigations on the emptying law of the propellant gas in after-effect perood under more complicated conditions.