为了优化金属膜片式隔舱的结构和预测膜片的打开压强,根据圆板的弯曲理论和脆性断裂理论,建立了金属膜片结构尺寸与预测打开压强之间的定量关系,用显示动力学的方法对膜片打开过程进行了模拟,在此基础上,进行了双脉冲发动机点火试车试验。结果表明,膜片断裂裂纹沿着预置缺陷槽扩展,最终断裂为6片较大的扇形碎片和无数块小碎片;随着预置缺陷槽的深度h和宽度2c的增加,膜片的打开压强变小,且h对打开压强的影响更大。膜片打开压强的试验值为1.02 MPa,与预测结果相差6%左右,验证隔板打开压强预测方法是可行的。

In order to optimize the structure of the metal diaphragm and to predict the opening pressure of the diaphragm in the process of dual-pulse motor design, the quantitative relationship between the structure scale and the predicted opening pressure is established according to the circular plate with bending theory and brittle fracture theory. And the opening process of the diaphragm was numerically simulated with the explicit dynamic finite element method. In addition, the ignition test was carried out. the results show that the fracture cracks extended to the preset defect grove, and the diaphragm ultimately fractured into 6 large fan-shaped fragments and countless small fragments. With the increase of the depth h and width 2c of the preset defect slot, the opening pressure on the metal diaphragm bulkhead decrease, and h has a greater impact on the opening pressure. The test value was 1.02 MPa, about 6% different from the predicted result,indicating that the pressure prediction method of diaphragm opening was feasible.