Experimental study on particle distribution of a particle-laden jet into a supersonic flow

Particle-laden Jet into Supersonic Flow (PJSF) is a critical process in chemical engineering, e.g., the spray technology. However, experimental studies on particle distribution have rarely been reported. For experimental research, we have developed a specialized experimental system for generating a supersonic flow (∼1406 m/s) and a sonic particle-laden jet. High-speed planar laser scattering technology was used to visualize the particles. Particle distributions were analyzed using three jet-to-free stream momentum flux ratios ($J$$J$) of 0.68, 0.44, and 0.27. The results indicate that particle aggregation occurs in the supersonic flow and forms two distribution patterns: streaky and torus-like. The former occurs in the supersonic mainstream, whereas the latter is located in the jet wake. Particle aggregation results in their inability to disperse quickly after entering the supersonic flow. The dispersion process of particles can be summarized as “clustering, stretching, and disintegrating”. Meanwhile, the parameter with the self-similar particle distribution was identified as ${\mathrm{D}J}^{0.577}$${\mathrm{D}J}^{0.577}$(D is the jet outlet diameter). The power-law function for the particle penetration depth was obtained. This paper presents the instantaneous and statistical distribution characteristics of particles in a supersonic flow through experiments. The power-law relationship is instrumental in predicting particle distribution and optimizing spray equipment.