Accession Number : ADA186527

Title :   Minor Scale Microwave Transmission Experiment and Investigation of Dust Instability Mechanisms.

Descriptive Note : Technical rept. 1 Sep 84-1 Aug 86,

Corporate Author : SRI INTERNATIONAL MENLO PARK CA

Personal Author(s) : McDaniel, Dan R

PDF Url : ADA186527

Report Date : 30 Sep 1986

Pagination or Media Count : 51

Abstract : An experiment was planned but not executed for a DNA high-explosive test that would resolve problems encountered in the application of conventional turbulence theory to dust effects. This experiment would have involved X-band rf transmissions through the turbulent pedestal, by measuring angle-of-arrival and changes in signal amplitude and phase caused by dust loading. These data would have been used to establish the spatial and temporal parameters of the dust-induced variations. Because of the difference between observed turbulence and that predicted by the Kolmogorov turbulence theory, plus the excessive dust-pedestal rise rates compared with the code predictions, a study of intrinsic mechanisms for toroidal instabilities was carried out. The study focussed primarily on vortex formation, trajectories, and circumferential instabilities, which are set forth as the principle mechanism for formation of the ring-wave-cell structure observed during DIRECT COURSE.

Descriptors :   *DUST, *MICROWAVE TRANSMISSION, *STABILITY, *TURBULENCE, *VORTICES, AMPLITUDE, ANTENNA PEDESTALS, DEOXYRIBONUCLEIC ACIDS, HIGH EXPLOSIVES, SCALE, SIGNALS, THEORY, TRAJECTORIES

Subject Categories : Radiofrequency Wave Propagation
      Meteorology
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE