EFFERVESCENT SUSPENSION SPRAY IN A GASEOUS CROSSFLOW

Abstract

A spray of suspension, forms mainly solid particles in a liquid phase from the atomization of two or multiphase flow, mainly solid particles in a liquid phase, and its transport phenomena by a gaseous crossflow have many natural and industrial applications. For example, injection of suspension jet in a high-speed flow is used in the emerging surface engineering process called suspension plasma spray. Typically, submicron ceramic oxide particles are mixed with water or ethanol to form a suspension that is injected in a plasma plume using different types of injectors. Injection parameters such as the type of injector and momentum flux influence the size, velocity, and trajectory of suspension droplets in the plasma and the microstructure of the deposited coatings. Using an effervescent atomizer, due to its capability in transporting flows with various rheological properties is promising for injection of suspension into the gaseous crossflow. In this study, an effervescent atomizer was employed to introduce a suspension radially into the flow of gas at room temperature. The spray of suspensions with different concentrations of glass particles in water was investigated in the crossflow by phase Doppler particle analyzer. The results were validated and supported by studying the spray by shadowgraph and light diffraction techniques. The results of this study provide a better understanding of the suspension spray generated by an effervescent atomizer in a crossflow configuration. It was found that the solid concentration of the suspension (up 10 wt.%) causes a slight decrease in size and brings the penetration of the suspension droplets in the gas flow.