隔舱式双脉冲发动机第Ⅱ脉冲点火过程数值仿真

Numerical simulation for the second pulse ignition progress in compartment dual-pulse motor

基于计算流体力学和相关点火理论,对双脉冲发动机第Ⅱ脉冲点火瞬态过程的流场进行了数值分析,并进行了发动机第Ⅱ脉冲点火试车试验。结果表明:在隔板打开前,第Ⅱ脉冲燃烧室高压区的位置由燃烧室前端向隔板移动,压强沿燃烧室径向变化较小,沿轴向变化较大,燃烧室头部和尾部近壁面区域一直处于低温;6 ms时隔板打开,第Ⅱ脉冲燃烧室压强下降0.5 MPa,药柱内孔前后端压强差波动剧烈,药柱内孔前端温度场下降600 K,而其他区域温度变化较小。隔板打开后,沿隔板下游第Ⅰ脉冲燃烧室轴线形成带状高温区,第Ⅰ脉冲燃烧室头部和尾部依次出现压强峰值,第Ⅰ脉冲燃烧室压强在18 ms时达到稳定,而温度在25 ms时达到稳定。试验测得的第Ⅰ、Ⅱ脉冲燃烧室压强-时间曲线和仿真结果吻合较好,表明该仿真方法具有一定的准确性。

Based on computational fluid dynamics and ignition theory,the flow field during the second pulse ignition of a dual-pulse solid rocket motor was numerically analyzed,and the test of the second pulse ignition of a dual-pulse solid rocket motor was conducted.Result showed that,before the diaphragm was opened,the position of the high pressure zone in the second pulse chamber moved from the front of the chamber to the partition,the pressure changed little along the radial direction of the chamber but more obviously along the axial direction,the near wall area of the second chamber head and tail was kept in the low temperature.The diaphragm was opened at 6 ms,and the pressure in the second pulse combustion chamber decreased by 0.5 MPa,the pressure difference at the front and rear ends of the inner hole of the propellant grain fluctuated violently,the temperature at the front end of the inner hole of the propellant grain decreased by 600 K,while the temperature in other areas changed little.After the diaphragm was opened,the downstream hole formed a zonal high temperature zone along the axis of the first pulse chamber,peak pressure appeared in the first chamber head and tail,the pressure of the first chamber reached a steady state at 18 ms,and the temperature of the first chamber reached a steady state at 25 ms.The pressure-time curves of the first and second chambers measured in test were in good agreement with the simulation result,indicating that the simulation method has certain accuracy.