WALL PRESSURE FLUCTUATIONS UNDER TURBULENT BOUNDARY LAYERS AT SUBSONIC AND SUPERSONIC SPEEDS
Abstract
This report reviews the theory of wall pressure fluctuations in incompressible flow, and shows how the character of the pressure fluctuations changes in passing from the flow to the wall. Attention is drawn to the more important interactions giving rise to the pressure fluctuations, as well as to the region of the boundary layer mainly responsible for the wall pressure fluctuations. The work is extended to include the effects of compressibility. It is found that an analysis similar to that of Phillips to appropriate, although, unlike the latter work, this new treatment is not restricted to the case of very high supersonic Mach numbers. The analysis makes use of the ratio a sub w as a large parameter, where a sub w is the speed of sound at the wall and u sub tau is the shear velocity. This is certainly true for a very wide range of Mach numbers provided that the wall is not subjected to large rates of heat transfer. It is shown that the wall pressure fluctuations are now the result of fluctuations in both the vorticity and sound mode. At high Mach numbers, the latter contribution is in the form of eddy Mach waves, as suggested by Phillips. On making certain assumptions regarding the dominant interactions, estimates of the magnitude and spectrum of the wall pressure fluctuations are made which show similar trends to the measurements of Kistler and Chen.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1963
- Accession Number
- AD0438848
Entities
People
- G. M. Lilley
Organizations
- AGARD