Fluidic Injection Scenarios for Shock Pattern Manipulation in Exhausts

Abstract

By numerically screening internal fluidic injection scenarios for the manipulation of the double diamond shock pattern in convergent–divergent nozzle exhausts, the individual importance of design parameters is demonstrated. It is found that the evolving shock pattern is sensitive to the injection location, whereas the persistence of the induced counterrotating vortex pairs is primarily governed by the injection pressure. Injection close to the nozzle exit generates secondary vortical structures, amplifying the fluctuations in the nozzle vicinity.