舱内爆炸角隅汇聚反射冲击波超压特性研究

为研究密闭舱室内爆角隅汇聚反射冲击波超压特性,利用缩比模型进行了某典型舱室内爆试验,得到远离角隅、两面角隅和三面角隅处的冲击波载荷,结合数值模拟研究了3种特征位置处冲击波传播规律及载荷特征。研究结果表明:远离角隅处壁面反射冲击波超压曲线呈现单峰结构,反射冲击波以球面波传播;距两面角隅一定范围内冲击波超压曲线呈现双峰结构,两面角隅冲击波超压曲线呈现单峰结构,角隅汇聚反射冲击波以椭球状传播;距三面角隅一定范围内冲击波超压曲线呈现多峰结构,三面角隅冲击波超压曲线呈现单峰结构,角隅汇聚反射冲击波以球面波传播;在合理假设条件下,根据量纲分析及数值模拟结果,得到首次冲击时角隅汇聚反射冲击波载荷经验计算公式。

Study on the corner overpressure characteristics of concentrated reflected shock wave due to internal blast in cabin

In order to study the propagation law and load characteristics of shock wave at the corner due to the internal blast in a closed cabin, a typical cabin explosion test was carried out using a scaled model. Overpressure loads of shock wave in one-sided, two-sided and three-sided corners were obtained. The EULER-FCT algorithm in the AUTODYN software was used to simulate the explosion test in the cabin, and the shock wave propagation law and load characteristics at three characteristic positions were studied. The results show that the overpressure time history curve of the wall reflected shock wave far from the corner is a single-peak structure, and the reflected shock wave propagates in a spherical shape. Within a certain range from the two-sided corner, the shock wave overpressure curve is a double-peak structure. The shock wave overpressure time history curve at the edge of the two-sided corner is a single-peak structure. And the corner convergent shock wave propagates in an ellipsoid shape. The peak overpressure and specific impulse of the two-sided corner convergent shock wave are about 1.83 times and 3.77 times more than those of the wall reflected shock wave at the same position. Within a certain range from the three-sided corner, the shock wave overpressure curve is a multi-peak structure. The shock wave overpressure time history curve at the three-sided corner is a single-peak structure. And the corner convergent shock wave propagates in a spherical shape. The converging ability of the three-sided corner to the shock wave is stronger than that of the two-sided corner. The peak overpressure and specific impulse of the converging shock wave in the three-sided corner are about 7.6 times and 10.4 times those of the wall reflected shock wave at the same position. Under certain assumptions, according to dimensional analysis and numerical simulation of typical compartments under different TNT charge internal explosion conditions, an empirical calculation formula of corner convergent reflected shock wave load at the first impact was obtained.