The research work focussed on the fine scale mixing noise of both subsonic and supersonic jets and the effects of nozzle geometry and tabs on subsonic jet noise. In publication 1, a new semi-empirical theory of jet mixing noise from fine scale turbulence is developed. By an analogy to gas...
To assess the noise-reduction benefits attainable from such configurations, it is necessary to develop appropriate acoustic evaluation tools. In this paper, a jet-noise-shielding- prediction methodology is described. The Tam–Auriault ("Jet Mixing Noise from Fine-Scale Turbulence," AIAA Journal, ...
The concept, first proposed by MIT researchers in 2019, "enables control of fine scale turbulence" according to Huyue Mao, one of the Shanghai researchers. The result is "reduction of mid- to high-frequency noise," Mao said. The Shanghai WIW solution improves upon earlier efforts by others ...
Lee et al.12 have also studied the slot jet MEMS (Micro-Elcctronic Mechanical Systems), to alter the fine scale flow structures within a boundary layer by 3-D simulation and the feedback control. Their results show that although the jets eliminated the targeted structures, however new ...
Furthermore, at the boundaries of the primary jet, a flow contraction occurs due to the capturing of flow, which eventually increases the turbulence of flow and promotes jet mixing at boundaries as compared to plane 2. This leads to an overall increase in deviation of the velocity values of ...
The net effect on redistributing heat and biogeochemical properties in the main basin will depend on the interplay between lateral stirring, vertical mixing, and the evolving large-scale basin circulation. How long warm intrathermocline eddies last, and thus how far they get under the sea ice, ...
matter of fact, flows at higher Reynolds numbers are of great interest for the understanding of turbulence, in that the separation between the large and the small scales of turbulence is large, which allows, for instance, to assess the proposed Reynolds number scaling of the small-scale ...
The jet impingement using pulsation technique can increase the heat transfer due to its unique features of high turbulence intensity, fluid flow instability, chaotic efficient mixing, and non-linear dynamic response of thermal and hydrodynamic boundary layers [186,238–241]. The convection heat ...
shock noise, and discrete tone jet screech. When an exhaust nozzle is operated at its design Mach number (when the nozzle exit pressure equals ambient) no shocks occur in the exhaust plume, and the only type of noise present is broadband mixing noise generated as a result of turbulence. ...
H. Champagne, "Orderly Structure in Jet Turbulence", Journal of Fluid Mechanics, Vol. 48, Part 3, August 1971. These experiments related to understanding the production of jet aircraft noise, and revealed that when the jet exit velocity, V, is oscillated about its mean value with an ...