In
aerospace industry,
chevrons are the sawtooth patterns on the trailing edges of some
jet engine nozzles that are used for
noise reduction. Their principle of operation is that, as hot air from the engine core mixes with cooler air blowing through the engine fan, the shaped edges serve to smooth the mixing, which reduces noise-creating turbulence. Chevrons were developed with the help of
NASA. Some notable examples of such engines include
GEnx and
Rolls-Royce Trent 1000.