Abstract
Jet noise is one of dominant noise sources in an aircraft engine. This paper describes a research on a jet noise reduction device, a chevron nozzle. Although chevron nozzles reduce the jet noise by an effect of promoting the mixing of high velocity jet and external flow, they tend to provide a thrust loss at the same time. In this research, experiments have been conducted using a small turbo-jet engine to evaluate the effect of chevron nozzles on the engine performance from both aspects of noise reduction and thrust loss. Three kinds of chevron shapes and two kinds of nozzle exit geometries have been used in the experiment and results have been compared with the reference nozzle.
