Project Highlight

Low Speed Aerodynamics

Mixing enhancement of engine exhausts

A cooperative research with the University of California, Irvine has focused on the study of jet mixing enhancement mixing by exploiting the natural instability within a convergent-divergent nozzle operated at overexpanded conditions. Results obtained for a single-stream jet in a configuration representative of the exhaust of gas-turbine engines show that the jet core can be suppressed and the thermal signature significantly reduced by the mixing increase. An analogous study for dual stream jets as found in large bypass turbofan nozzles also shows that the jet mixing is increased and the jet velocity is reduced. A complete survey of acoustic measurements in the far-fields of these jets was performed inside an anechoic chamber.