The role of shear-layer instability waves in jet exhaust noise

Author:

Moore C. J.

Abstract

Large-scale structures in the form of instability waves are an inherent part of a shearlayer mixing process. Such structures are shown to be present in an acoustically and aerodynamically well behaved jet even at high Mach numbers. They do not directly radiate significant acoustic power in a subsonic jet, but do govern the production of the turbulent fluctuations which radiate broad-band jet noise. Over the whole subsonic Mach number range, a significant increase in jet noise can be produced by exciting the shear layer with a fluctuating pressure at the nozzle of only 0·08 % of the jet dynamic head but with the correct Strouhal number. Such excitation by internal acoustic, aerodynamic or thermal fluctuations could explain the variability of jet noise measurements between different rigs and could also be responsible for some components of ‘excess’ noise.

Publisher

Cambridge University Press (CUP)

Subject

Mechanical Engineering,Mechanics of Materials,Condensed Matter Physics

Reference52 articles.

1. Schubert, L. K. 1972 Numerical study of sound refraction by a jet flow.J. Acoust. Soc. Am. 51,439–462.

2. Wooldridge, C. E. , Wooten, D. C. & Amaro, A. J. 1971 The structure of jet turbulence producing noise.N.A.S.A. Contractor Rep. no. 126483.

3. Pfizenmaier, E. 1973 On the instability of a sound influenced free jet.E.S.R.O. Tech. Trans. no. 122. (Translation of DFVLR Berlin Rep. DLR-FB 73–69.)

4. Jones, B. G. & Planchon, H. P. 1971 A study of the local pressure field in turbulent shear flow and its relation to aerodynamic noise generation.N.A.S.A. Contractor Rep. no. 134493.

5. Lighthill, M. J. 1961 Sound generated aerodynamically. Bakerian Lecture.Proc. Roy. Soc. A 267,147–182.

Cited by 419 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3