Improvement of Cooling Efficiency of Plasma Spray Gun Nozzle

Raghunandan M S

The nozzle of a plasma spray gun is one of the important parts that have to be considered for the better improvement of life of the plasma spray gun. This study simulated the nozzle using CFD (Computational Fluid Dynamics) by considering parameters like velocity and fluid flow direction. A numerical model is developed using SIMPLE (Semi Implicit Method for Pressure Linked Equations) for fluid flow and heat transfer conditions. Due to the formation of local turbulence, a static-water region is formed which decreases the efficiency of the cooling system. The nozzle is heated up with a temperature of 8000 K at the heat source point. Due to the characteristic of the nozzle, the heat source is assumed to fall at a point and is supplied with a temperature of 8000 K. The nozzle is also susceptible to burn out due to over-heating. The seal gasket at the rear of the nozzle is also susceptible to burn out due to the heat exchange between water and the inner wall of the nozzle. This can be overcome by changing the direction of water flow and also changing the water flow velocity through the coolant channel.