固体火箭发动机燃烧稳定性预估的三维计算方法

针对一个变截面开槽管状装药的单室双推力发动机,讨论了应用三维声学有限元法分析,确定燃烧室内腔的声学特性,以及在此基础上进行的发动机燃烧稳定性预估的三维计算方法。应用本文编制的计算程序试算的结果表明:燃烧室内腔前10阶固有振型的预估误差不大于3％;该发动机的燃烧稳定性接近临界状态,与地面试验情况定性一致。

Three-Dimensional Calculation Method for the Prediction of the Combustion Stability of Solid Rocket Motors

For a single-chamber and double-thrust solid rocket motor loaded with slotted-tube propcllant grain of variable sections, this paper discusses how to determine the acoustic properties inside the combustion chamber by using three-dimensional acoustic finite-element analysis. The three-dimensional calculation method for the prediction of the combustion stability of the rocket motor based on that is explained. The calculation results obtained from the calculation progrom demonstrate that: the prediction error of the natural vibration patterns below 10th order inside the combustion chamber is not more than 3%; the combustion stability of this motor approaches critical state and is qualitatively in accordance with ground test.