Aero-acoustic performance characteristics of duct burning turbofan exhaust nozzles

A recent experimental investigation has identified the aero/acoustic characteristics of exhaust nozzles for duct heating turbofan engines over a range of simulated flow conditions. Jet noise and performance levels are summarized for a series of coannular nozzles representing both acoustically suppressed and unsuppressed designs operating in a static environment. The basic coannular nozzles were found to provide inherent noise suppression. Multi-element suppressor nozzles provided additional noise suppression, but with appreciable thrust loss. The impact of these results on the advanced supersonic transport studies is also presented, indicating potentially large reductions in take-off gross weight or community noise footprints.