Mixer-Ejector Nozzles: Acoustic and Thrust Characteristics

The paper presents the review of the CIAM/TsAGI investigations of mixer-ejector models, which could be considered to be prototypes of real variable area nozzles for future supersonic aircraft. Acoustic and aerodynamic characteristics of both 2-D and axisymmetrical models were obtained. The influence of nozzle geometry (number of lobes, lobe shape, ejector length, auxiliary inlets in the ejector walls) on its noise and thrust performances is discussed. The experimental data show that the best mixer-ejector configuration tested provides a noise reduction efficiency of about 3 ∼ 3.5 PNdB per 1% thrust loss at static conditions.