Jet impingement onto a limited-area heated plate: Conical nozzle considerations

One of the applications of conical nozzles is in laser gas assisted processing. Depending on the type of the process required, the assisting gas can be inert non-reactive or undergoes a chemical reaction such as oxygen. Moreover, nozzle geometric configuration is important for improved processing. In the present study, conical nozzles with different cone angles are considered. Flow exiting the conical nozzle and impinging onto a limited-area heated plate is modeled numerically using a control volume approach. The influence of nozzle cone angles on the flow field and heat transfer characteristics are examined. Three different gases are employed in the simulation. This enables to compare the influence of gas properties on the flow and heat transfer characteristics. The fully developed turbulent pipe flow is also considered for comparison purpose. It is found that the heat-transfer coefficient across the heated spot increases as the nozzle cone angle increases. This signifies for air.