Heat transfer and convection characteristics of a superheated turbulent jet interacting with a solid object

Abstract

The present study attempts to investigate numerically the heat transfer and associated convection characteristics arising from the interaction between a superheated turbulent argon jet and a solid object, a topic of critical importance to the modern rapid solidification processes. Two flow configurations are simulated, one a planar case that includes a slot jet issued into a circular cylindrical chamber and impinged on a solid cylinder, and the other an axisymmetric case that includes a circular jet issued into a circular cylindrical chamber and impinged on a solid sphere. The effects of the turbulence intensity of the incoming jet on the convection and heat transfer characteristics are studied; in both configurations the turbulent transport can help enhance the heat transfer rate, causing highly non-uniform Nusselt number distributions around the object. Furthermore, due to the differences caused by the two geometries, flow separation can be completely suppressed by high turbulence intensity in the planar configuration, but not in the axisymmetric configuration. Efforts are made to interpret and elucidate the various characteristics exhibited by the solutions obtained, and to gain physical insights of the relevant processing conditions.