嵌银丝端燃装药耦合传热的内弹道数值分析

Numerical study on the interior ballistics of grain embedded with silver-wire coupled convective heat transfer process

针对内埋金属丝端燃装药燃烧过程中出现压强峰值的问题,耦合金属丝区域的传热过程,建立了内埋金属丝端燃装药燃速计算模型。通过对有限元软件,进行二次开发实现了内埋金属丝装药传热及燃面退移过程的模拟。结果显示,沿金属丝被加热推进剂的温度、燃速、增速比受燃烧室压强影响较大。在此基础上,进行了嵌单根银丝端燃装药内弹道仿真,得到了压强,燃面面积,沿金属丝燃速随时间变化规律。结果表明,计算模型可有效模拟内埋金属丝端燃装药燃烧过程,与实验数据吻合较好,从理论上解释了燃烧过程中出现压强峰值的实验现象。

The study focuses on the mechanism of the appearance of initial pressure peak when using the embedded wire on the end burning grain.The convective heat transfer process was modeled and the computational model for the velocity of burning was created.The heat transfer process and the motion of the burning grain were simulated via the secondary development of the finite ele- ment software.The result indicates that the temperature, the burning velocity and augmentation ratio of the grain along the wire is strongly ＂affected by the pressure in the combustion chamber.Based on this finding,the interior ballistics simulation of the grain with only one embedded wire was simulated , thereby the pressure , the burning area and the burning velocity along the wire versus time were obtained.The good agreement with the experimental data indicates that the computational model can be used properly to simu- late the burning process of the grain with wires. In addition, the appearance of the initial pressure peak during the burning process was explained theoretically.