在工业爆炸灾害和国防军事领域, 气体和燃料颗粒组成的燃料云团的非定常两相燃烧爆轰会对周围介质产生毁伤破坏效应, 该效应与燃料运动特性和空间质量分布密切相关. 建立了二维气液两相流模型, 基于有限体积方法、利用二阶精度的守恒型单调迎风格式 (monotonic upwind scheme for conservation laws, MUSCL), 以正庚烷燃料为对象, 对爆炸驱动下冲击波在两相介质中传播、 燃料云团界面不稳定性演化、冲击波诱导旋涡机制, 以及颗粒初始运动性质开展数值研究. 可以得出, 波与燃料颗粒相互作用是一个动量、能量传递的过程. 当冲击波扫过两相介质, 压力发生衰减, 与比例距离 Z 满足幂数律关系. 同时, 波在云团中发生反射和折射, 两相介质中波阵面发生弯曲. 燃料介质获得和波同向的平动速度. 如初始粒径为 60 $\mu $m 的燃料云团, 在 112 $\mu $s 时间内, 云团扩散的径向速度提高到 22.8 m/s. 此外, 当波作用于燃料云团, 气液界面的流场发生扰动. 当波扫过燃料云团外缘, 会产生大尺度结构的旋涡, 增强了原来未受扰动流场的湍流度. 同时, 界面附近流场的密度和压力梯度诱导出涡量, Richtmyer-Meshkov不稳定性 (Richtmyer-Meshkov instability, RMI) 的发展使得界面生成一系列小尺度涡. 大、小尺度的涡促进了湍流的发展, 加剧了燃料云团的运动和颗粒的分散, 为云团的膨胀及后续两相爆轰的发生提供重要条件.

In industrial explosion disaster area and the military area, the unsteady two- phase combustion detonation of the fuel cloud composed of gas and fuel particles can have a destructive effect on the surrounding medium, which is closely related to fuel motion characteristics and mass spatial distribution. In this paper, a two-dimensional gas-liquid (two-phase) flow model is established. Based on the finite volume method and the two-order accuracy monotonic upwind scheme for conservation laws (MUSCL) difference scheme, the numerical study on propagation of the shock waves in a two-phase medium, instability evolution of the fuel cloud interface, the mechanism of shock induced vortices and the initial motion of fuel cloud are conducted based on $n$-heptanes as the fuel. The research results show that the interaction between shock wave and fuel is a transfer process of momentum and energy. When the shock wave sweeps through the two-phase medium, the pressure attenuates and the relation with the proportional distance satisfies the power law. Moreover, the reflected wave and refraction wave are generated in the cloud and the wave front in the gas-liquid medium is bent. The liquid fuel obtains the same propagation direction of wave. For the initial particle size 60 $\mu $m, the fuel cloud will increase up to 22.8 m/s during the period of 112 μs. In the meantime, when the shock wave acts on the fuel cloud, then the flow field at the gas-liquid interface is disturbed. During the wave passing around the fuel cloud, large-scale vortices will be generated around the outer edge of cloud, which enhances the turbulence intensity of the original undisturbed flow field. Furthermore, the vorticity is induced by the density and pressure gradient of the flow field near the interface, and the development of Richtmyer-Meshkov instability (RMI) makes the interface generate a series of small-scale vortices. Large and small-scale vortices promote the development of turbulence, which also enhances the movement of fuel cloud and the dispersion of particles. It provides important conditions for the expansion of the cloud and subsequent two-phase detonation.