单次爆震载荷作用下爆震室结构响应的数值研究

摘要

针对单次爆震波作用下爆震室结构响应的问题，建立了脉冲爆震发动机爆震室的轴对称有限元模型；利用爆震波的Chapman-Jouguet简化模型（C—J模型）求出了爆震载荷的离散数据；应用ANSYS软件对不同爆震波传播速度下爆震室的结构响应进行了分析，得到了爆震室不同位置处动力放大系数随爆震波速度变化的曲线，并对几种不同条件下的爆震室放大系数做了分析。研究发现：爆震波速度对爆震室结构响应与周向应力放大系数沿爆震室轴向的分布趋势均有较大影响；当爆震室壁厚减小时，与结构对应的临界速度附近的周向应力值增大，当爆震波速度远大于结构的临界速度时，随着壁厚的减小，放大系数的值变化不大，可以按固定的放大系数进行爆震室壁厚强度计算。%Aiming at the structural response of the detonation combustor to single detonation loading, an axisymmetric finite element modal of the detonation combustor is established. A set of detonation pressure as a discrete version is obtained using simple Chapman-Jouguet modal of detonation wave （ C-J modal）. The structural responses of the detonation combustor to different detonation wave speeds are analyzed by using the ANSYS software ; the amplification factor curves of the detonation combustor at different locations are drawed ; and then several amplification factors for several different conditions are also analyzed. It＇s found that the effect of the detonation wave speed is important in researching structural response of the detonation combustor and the amplification factor curves of hoop stress in the axial direction. We can reduce the thickness of the detonation combustor by optimizing with a fixed amplification factor when the detonation wave speed is far higher than the critical speed of the detonation combustor.