Shock Wave And Particle Interaction Experimental Research

The process of aerosol's dispersing and forming into cloud group was studied by theoretic analysis and experimental. The main researches are as follows: the moving law of inside and outside interface of the liquid or solid micro particles in the early phase droved by shock wave. Determining of the characteristic parameters of cloud group shape, particle size and density in the process and the process of droplets' deformation and fragmentation.Experimental indicated that deformation and fragmentation process of water droplets (diameter d₀= 1～2mm) under weak shock wave action (Mach Member Ms=1.05～1.26) is broken stripping process. Broken stripping process can be divided into two phases: the first is droplets' deformation, time of this process is about several hundred microseconds; the second is droplets' peeling atomization, time of this process is several milliseconds. The time of droplets deformation that achieve the same degree depend on the Mach number of shock wave, the time is inversely proportional with the shock wave's Mach number. Droplets' broken time is also inversely proportional with the shock wave's Mach number; when under the shock wave of same intensity, the larger of droplets' diameter, the more time droplets' broken needed.The results indicated that the formation of cloud's dispersal and the particles' track are related with intensity of the shock wave, material, size and concentration of particles etc.The flow topology during the dispersal process ranges from a dense granular flow to a dilute gas-solid flow, which is incorporated with two-phase fluid. Considering the dynamic characteristics during shock wave interaction with the solid particles, as the particle starts to move, particles cloud immediately becomes blur both in longitudinal and transverse direction, it means the average concentration of the cloud is reduce.