Journal ArticleDOI
Effect of impingement surface roughness on the noise from impinging jets
Reads0
Chats0
TLDR
In this paper, the effects of roughness of the impingement plate widens the staging region of noise and the effect of nozzle-to-plate spacing distance and nozzle pressure ratio are investigated.Abstract:
This paper presents extensive acoustic measurements on jets impinging on surfaces of various surface roughness values. Besides surface roughness, the effects of nozzle-to-plate spacing distance and nozzle pressure ratio are also investigated. Turbulent mixing noise and tonal noise are explained using far-field wall-jet velocity and impingement region temperature fields. The results demonstrate that roughness of the impingement plate widens the staging region of impingement noise. In general, high speed jet impinging on a rough plate generates less noise compared to a smooth plate. When tones are removed from the spectra, it is found that acoustic power monotonically decreases with increasing surface roughness. Thermal imaging in the stagnation region indicates that whenever tones are present, the temperature at the stagnation region is high. Further, sound pressure directivity pattern of impingement noise is constructed by superimposing a wall-jet and a free jet in the appropriate orientations.read more
Citations
More filters
Journal ArticleDOI
A review of impinging jets during rocket launching
TL;DR: In this article, the authors present an overview on progress and perspectives of the jet impingement research for rocket launching and discuss the interaction of impinging jets with multiphase flows.
Journal ArticleDOI
Analysis of the performance of a new developed shear stress transport model in a turbulent impinging jet flow
TL;DR: In this article, a developed Shear Stress Transport (SST) model has been used for numerically simulating the problem of turbulent round jet impingement heat transfer, and the results showed that the inner peak of heat transfer is connected with the radial pressure gradient at the stagnation point.
Journal ArticleDOI
Sound source mechanisms in under-expanded impinging jets
TL;DR: In this paper, an under-expanded supersonic jet impinging on a flat plate is investigated by means of acoustic, particle image velocimetry and wall pressure measurements.
Journal ArticleDOI
A review on multiple liquid jet impingement onto flat plate
Shikshit Nawani,Maharshi Subhash +1 more
TL;DR: In this article, the authors summarized the state of the art of the process of multiple jet impingement onto flat plate and highlight the future scope of research space in this field.
Journal ArticleDOI
Experimental investigation of heat transfer of impinging jet on a roughened plate by a micro cubic shape
TL;DR: In this article, an experimental study of average heat transfer from air jet impinging on a rough plate by a micro cubic pin is investigated, and the main objective of the present study is to investigate the effect of...
References
More filters
Journal ArticleDOI
An experimental study of the oscillatory flow structure of tone-producing supersonic impinging jets
TL;DR: In this article, an experimental investigation into the structure of a supersonic jet impinging on a large plate is presented, and the instability of the jet depends on the location of the plate in the shock cell structure of the corresponding free jet and the strength of the standoff shock wave, rather than on the occurrence of recirculation zones in the impingement region.
Journal ArticleDOI
Wall pressure and shear stress measurements beneath an impinging jet
C.V. Tu,David Wood +1 more
TL;DR: In this paper, the authors measured wall pressure and surface shear stress under a plane, two-dimensional, turbulent jet impinging normally onto a flat surface and found that the wall pressure distributions are nearly Gaussian, independent of Reynolds number, and closely balance the momentum flux from the jet nozzle as H D varies.
Journal ArticleDOI
Control of supersonic impinging jet flows using supersonic microjets
TL;DR: In this paper, a unique active control technique was attempted with the aim of disrupting the feedback loop, diminishing the e ow unsteadiness, and ultimately reducing the adverse effects of supersonic impinging jets on the nearby aircraft structures and landing surfaces.
Journal ArticleDOI
Annular synthetic jet used for impinging flow mass-transfer
Zdeněk Trávníček,Václav Tesař +1 more
TL;DR: In this article, an annular synthetic jet was investigated experimentally, both with and without an opposing impingement wall, and the experiments involved smoke visualization and mass transfer measurement on the wall by means of naphthalene sublimation technique.
Journal ArticleDOI
The near wall jet of a normally impinging, uniform, axisymmetric, supersonic jet
J. C. Carling,B. L. Hunt +1 more
TL;DR: In this paper, the authors investigated the supersonic near wall jet produced by directing a uniform axisymmetric jet of air normally onto a large flat plate and found that the wall-jet region is largely independent of whether or not a bubble occurs in the shock layer.