Reduction of Jet Noise in the Presence of a Closely Spaced Plate

The paper presents the results of an experimental study of a subsonic turbulent jet noise. The cases of an isolated jet and a jet in the presence of a closely spaced plate are considered. The studies were carried out for the conical and equivalent-sized chevron and lobed nozzles. The work demonstrates the possibility of reducing both broadband jet noise and low-frequency jet–plate interaction noise using a lobed nozzle.