3-DIMENSIONAL COMPUTATIONS OF TRANSVERSE HELIUM JETS IN A SUPERSONIC AIR-FLOW

This paper describes a study concerning the numerical simulation of a sonic helium jet through a transverse nozzle in a flat plate exhaustin g normally into a supersonic air flow. Three-dimensional Reynolds-aver aged Navier-Stokes equations coupled with the modified Baldwin-Lomax a lgebraic turbulence model and relevant species equations are solved by using a finite-volume upwind scheme. In this approach, Roe's flux fun ction, explicit multi-stage integration and multi-block procedure are applied to achieve the steady state solution efficiently. The Roe's fl ux function is modified to suit the simulation of helium-air mixing. T he comparison between two-dimensional calculated results with experime ntal data of surface pressure shows good agreement. The results of thr ee-dimensional computations for square, circular and rectangular jets are presented, and the essential flow features including induced shock s, upstream separations, and downstream primary and secondary vortices are adequately simulated.