ATTENUATION OF ACOUSTIC NOISE FROM SUPERSONIC JET NOZZLE

This project focuses on acoustic noise suppression at the aft of the jet nozzle. This is due to turbulence structures and these turbulence structures are generated by the flow instability due to pressure fluctuation that is created at the nozzle exit. Some techniques have been employed in the past decade to weakening the acoustic noise which includes chevrons at the nozzle aft. The acoustic study reveals that addition of chevrons to the nozzle reduces the sound pressure level reasonably with an adequate reduction in performance. Work includes the modification in the design of chevrons. The numerical study has been carried out using a valid 2D pressure based, k-ℇ turbulence model. The supersonic nozzle is designed for Mach number of 2.8. The analysis technique involved is SPL. We compare the nozzle base model with the chevron nozzle and with modified chevron nozzle. Results shoes the amount of sound got reduced in db.