NUMERICAL STUDY OF THE MIXING EFFICIENCY INSIDE THE PLENUM CHAMBER OF A PLASMA WIND TUNNEL

摘要

This paper describes a preliminary numerical study on the mixing process inside the plenum chamber of a plasma wind tunnel. Cold gas is injected into the chamber to mix with the hot gas from an arc heater to generate an overall total enthalpy lower than 10MJ/kg. The mixing is analysed by a Navier-Stokes solver with different turbulence models. The formation of large vortices downstream from the injection and the interactions among these vortices and the injected cold gas as well as the high temperature effects are highlighted and discussed. Comparison with an empirical formula for mixing efficiency is included.