大爆破爆炸冲击波在破碎岩体间传播的数值模拟研究

NUMERICAL SIMULATION ON SHOCK WAVE PROPAGATION IN CRUSHED ROCKS DURING INTENSE BLASTING

大爆破过程中产生的能量大部分作用在周围岩体破坏上,部分能量转化为冲击波在破碎岩块间传播,同时对已破碎的岩块再次产生松动破坏。应用流体力学方法,建立了以可压缩湍流流动为基础的爆炸冲击波在破碎岩体间传播的数学模型。通过数值分析和模拟结果表明,破碎岩体的障碍物作用对爆炸冲击波的传播存有激励机制。岩石的破碎是由于冲击波和爆炸生成气体膨胀动力共同作用的结果。当冲击波在破碎岩块间传播时,湍流流动受壁面的影响很大。冲击波在通过孔隙后其波阵面的压力衰减程度较大。速度通过孔隙过程中增加的幅度较大,而温度的变化不明显。

Using the theory of fluid dynamics, the mathematical model of shock wave propagation in rocks is setup on the basis of compressible turbulent flow. The simulation results show that the crushed rocks have encouraging effects like the barricade on shock propagation. The rock is crushed under the condition of co-interaction between shock and dynamic expansion of products by the blast. The turbulent flow is mainly effected by the wall surface when the shock wave is propagating. The pressure in wave front is greatly attenuated while the shock wave propagates through the small opening of rocks. However, the velocity is increased greatly and the temperature change is not evident.