A Computational and Experimental Investigation into Radial Injection for Suspension High Velocity Oxy-Fuel (SHVOF) Thermal Spray

Abstract

Suspension high velocity oxy-fuel thermal spray typically utilizes axial injections of suspension into the combustion chamber. There are certain cases where the oxygen-sensitive nanoparticles benefit from a reduction in the time and temperature spent in the gas flow. Therefore, a radial injection outside of the nozzle can enable deposition of oxygen-sensitive nanomaterials. This study investigated the effect of the suspension flow rate, angle of injection and the injector diameter on the in-flight particle conditions. The combustion reaction is modeled using the eddy dissipation concept model with a robust reaction mechanism and compared to the current approach within the literature. This approach has not been employed within SHVOF thermal spray and provides a robust treatment of the reaction mechanisms. The suspension was modeled using a two-way coupled discrete particle model. Experimental observations were obtained using high-speed imaging, and observations of the liquid jet were compared to the numerical values.