Shock Wave And Particle Interaction

Interactions of Shock waves with micro-particles are always used in industry dust explosion and military cloud detonation weapon. It possesses very important research value, and becomes hot topic. However, research results are not perfect because of the complex process involved various knowledge, such as fluid dynamics, aerodynamics, explosion mechanics and heat etc. So there still need further research.The present paper is devoted to experimental and numerical investigation of the shock wave propagation in a mixture of gas and some object. Experimental investigation systematically inspected how the various factors (such as shock wave strength, liquid film thickness, and particle size, object density) affect the flow when shock wave interacts with micro-particle. The experiments are completed in special designed shock tube. And numerical simulation studies the parameters of FAE. Main innovative results are as follows:(1)The density of liquid cloud would be uniform after completely expanded shock wave interaction with the liquid film. The completely expanded shock wave can be obtained as long as the shock wave move 15mm after wave leaving the tube export. While the density of liquid cloud would not be uniform after the shock wave interact with the liquid film at tube export because the wave is a discounted expanded wave.(2)Liquid could shapes are changed with the initial liquid film thickness changed when the same shock wave interact with different liquid film. Moreover, followed the increasing of initial liquid film thickness, cloud shapes are changed from spindle shape to sphere, as well as the relation of cloud volume with initial liquid film thickness is a U-shaped curve.(3)Degree of uniformity of liquid cloud is proportional to the Mach number while the shock wave interacts with same thickness of liquid film. The shape of cloud can be changed as the kind of liquid changed. Moreover, after the more viscous liquid interacting with shock wave, its cloud would appear sunken point. Over time, sunken point turns to peak. At the same time, the liquid whose surface tension is smaller is easy to change to be dendritically on the cloud edge after the shock wave propagates in a mixture of gas and the liquid.(4)Behind shock wave, the particles speed of horizontal movement is smaller than vertical movement obviously. And the particle trajectory is a parabola, while cloud shape is the cone during the process. Moreover, initial velocity of particle movement and inverse to particle size as the Mach number keep still.(5)Main deformation forces and object deformations are different as the different density objects interact with shock wave. The force for low density object deformation is the incident wave. And the air can invade the low density object. For the larger density object, the deformations force is the transmission wave, and the air can not invade it. For the high density object, the deformations force is the transmission wave and diffraction wave, and the air can not invade it else.(6)Use different mechanisms made the mathematical model of drops clouds dispersed in air by high explosive. The result indicated that the drop fist breakup time is military magnitude. And droplet near the shell and the region of detonation products is larger than those in the other position.