A Sequence of Transient Acoustical Sources in an Idealized Jet,
Abstract
A sequence of transient acoustical point sources is considered as a noise generator in an idealized two-dimensional jet. Each transient source starts at the same position relative to the stationary nozzle (or external air), drifts downstream with the local fluid for a given time, then disappears. As each source disappears a new one appears at the initial position. The far field mean-square pressures are obtained from a previous analysis of the effects of permanent sources, and are converted from a coordinate system fixed in the source to 'retarded' coordinates fixed in the external air (or stationary nozzle). In the examples, two jet velocity profiles are studied, first a jet composed of linear velocity profile shear layers meeting at the center, and second a uniform jet bounded by velocity discontinuities. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1970
- Accession Number
- AD0715750
Entities
People
- E. W. Graham
Organizations
- Boeing