SOME ASPECTS OF TURBULENT SCATTERING OF ELECTROMAGNETIC WAVES BY HYPERSONIC WAKE FLOWS
Abstract
This analytical study of the turbulent scattering of electromagnetic waves is directed to certain features of the phenomenon considered as peculiar to hypersonic wakes. Effects of flow intermittency, non-isotropy of the turbulence structure, and finite width of the wake on the scattering cross section in its frequency and aspect-angle dependence are of primary concern. Phenomena of turbulence relevant to the scattering problem are briefly discussed. In particular, it is shown that electron-density fluctuations of a turbulent nature, in addition to those caused by ''turbulence'', will be produced by the intermittency behavior of turbulent wake flows. This fluctuation is found to depend on the mean electron-density distribution, and Townsend's intermittency function. Phenomenological consideration of the physical process by which the turbulent electron-density fluctuations are likely to be produced in hypersonic wakes yields an expression for the intensity of the fluctuations in terms of the gradient of the mean electron-density distribution, the intensity of the turbulent velocity fluctuation, and a turbulence scale of the turbulent velocity field. Application of the above considerations to turbulent scattering by underdense wakes has been made.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1963
- Accession Number
- AD0429172
Entities
People
- K. T. Yen
Organizations
- General Electric