坑道内爆炸冲击波相似律问题探讨

摘要

The blast experiment in tunnel entrance of different explosive charge was conducted to study the simi-larity law of blast wave in tunnel and the shock wave in prototype and the model tunnel was calculated by numerical simulation software ANSYS/LS-DYNA. The results show that the blast wave with different explosive charges in iden-tical tunnel does not fit the similarity law,unlike in free atmosphere. If the geometry of prototype and model tunnel is similar and the ratio of charge to geometric is cubic,the blast wave in prototype tunnel and model tunnel will conform to the similarity law. The numerical simulation results of blast wave conform to the similarity law when the grid size of the prototype tunnel and model tunnel conform to the corresponding geometric similarity ratio. The grid density in tunnel cross-section between 1675 and 2977 meets the precision requirement well.%为研究坑道内爆炸冲击波相似律问题，进行了不同药量坑道堵口爆炸实验，并利用 ANSYS/LS-DYNA软件对原型坑道与模型坑道爆炸冲击波进行数值计算。结果表明：与自由大气中不同，同一坑道内不同药量爆炸产生的冲击波不符合爆炸相似律；若原型坑道与模型坑道几何相似，装药量之比为几何相似比的三次方，则原型坑道与模型坑道内爆炸冲击波符合爆炸相似律；坑道内爆炸冲击波数值模拟时，若原型坑道与模型坑道网格尺寸符合相应的几何相似比，则冲击波计算结果满足相似律，当坑道截面网格密度为1675~2977时可以达到计算精度要求。