Question

How to reduce engine noise?

(a) By using chevron nozzle

(b) By using high velocity jet

(c) Using small diameter and high velocity jet

(d) Higher exhaust jet with less diameter of exhaust

I had been asked this question in an interview for job.

The doubt is from Configuration Layout Considerations in division Configuration Layout Considerations of Aircraft Design

Answer 1

Right answer is (a) By using chevron nozzle

For explanation: Chevron nozzle is used to reduce the engine exhaust aural signatures. Chevron nozzle accompanies saw tooth pattern at the trailing edge. High velocity jet will produce more noise due to air shear layer effects.