STATISTICAL PROPERTIES OF THE TURBULENT VELOCITY FLUCTUATIONS IN THE MIXING REGION OF A ROUND SUBSONIC JET,
Abstract
The noise sources in a jet can be related to the turbulent velocity fluctuations in the mixing region. The structure and characteristics of the turbulence have been studied experimentally and the results are given in this report. It was found that the statistical characteristics of the turbulence can be expressed in terms of simple kinematic relationships as far as time averaged quantities are concerned. Measurements are presented which are expressed as probability distribution functions of the velocity about its mean value, or more simply as flatness and skewness factors. All the measurements taken together imply a fairly simple model of the turbulent structure which consists of flattened disc shape eddies of roughly equal axial and circumferential scale, with a radial scale of one-third the axial value. These are distributed randomly in the mixing region and have, in general, a different velocity from that of the mean flow. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1963
- Accession Number
- AD0436672
Entities
People
- M. J. Fisher
- P. O. A . L. Davies
Organizations
- AGARD