点火过程对小型固体火箭发动机内弹道影响

为了研究某小型固体火箭发动机点火过程对内弹道性能的影响,建立包含点火过程的小型固体火箭发动机的内弹道数值研究模型和试验验证方案,对点火药量为1.0 g、0.8 g、0.6 g和0.4 g的发动机进行了内弹道数值研究,试验研究了点火药量为1.0 g和0.8 g两种情况,数值计算结果与试验结果基本一致。研究结果表明:小型固体火箭发动机由于燃烧室体积小,点火过程对内弹道影响明显;点火药量越大,点火药装填密度越大,引起压力峰值越大,稳定工作时间越短;经验估算得到的1.0 g点火药量产生了过高的压力,是稳定压力的三倍,0.8 g的点火药量能够满足点火可靠性和总体设计要求,产生最大压力为27.08 MPa,稳定工作时长159 ms,建议该小型火箭发动机的点火药量为0.8 g。

Effects of Ignition Process on the Internal Ballistics of Small-size Solid Rocket Motor

To study the effects of ignition process on interior ballistic performance of a small-size solid rocket motor, the model for interior ballistic calculation including ignition process of small-size solid rocket motor and verification plan were set up. The numerical calculations interior ballistic performance with 1.0 g, 0.8 g, 0.6 g and 0.4 g igniter masses were carried out. The tests of 1.0 g and 0.8 g igniter mass were done. The compute result and test data were basically consistent. The results indicated that: the effect of ignition process on interior ballistic about small-size solid rocket motor is obvious for the small combustion chamber volume. The igniting charge density and pressure peak increase, stable operating time of motor decreases as the igniter mass increases. The 1.0 g igniter mass is estimated by empirical formula, 1.0 g igniter mass brings too high pressure to motor, the value of pressure reaches three times the stable pressure. 0.8 g igniter mass meets ignition reliability and general design requirements, and the maximum pressure is 27.08 MPa, and stable work time is 159 ms, and 0.8 g igniter mass is suggested for the small-size solid rocket motor.