Accession Number:

ADA512151

Title:

Basic Materials for Electromagnetic Field Standards

Descriptive Note:

Final technical rept. 1 Jun-30 Nov 2003

Corporate Author:

RUSSIAN ACADEMY OF SCIENCES NOVOSIBIRSK INST OF THEORETICAL AND APPLIED MECHANICS

Personal Author(s):

Report Date:

2003-03-04

Pagination or Media Count:

165.0

Abstract:

This report results from a contract asking Institute of Theoretical and Applied Mechanics as follows Study is devoted to basic research of stability and transition of hypersonic boundary layer around blunted cone. Nosetip bluntness effects have very strong influence on laminar turbulent boundary layer transition. These effects are very complex because the nosetip-region boundary layer may be under the influence of by-pass phenomena. Tollmien-Schlichting waves, and Goertler vortices. Results of fulfilled stability experiments do not agree with computations. But such a comparison is not at all valid because natural disturbances were studied in former experiments. In the present project the artificial wave-packet method will be applied to get the necessary data for waves for various single incidence angles. Obtained results will be used for a correct comparison between theory and experiment. The experimental investigations will be performed in the blowdown wind tunnel T-326 in Hypersonic Flow Laboratory of ITAM SB RAS at Mach 6 . A point-source g low-discharge perturber will be used to excite the boundary layer frequency band corresponding to the first and second mode waves. Mean flow and pulsations measurements will be carried out using hot-wire anemometer. Detailed experimental data on the position of the laminar-turbulent transition, characteristics of natural disturbances and evolution of artificial disturbances in the boundary layer of a cone with different nose bluntness at Mach number M6 will obtained. The proposed project will allow a bank of experimental data on the stability of the hypersonic boundary layer to be compiled. As a result, a better insight into the processes taking place in hypersonic boundary layers will be gained.

Subject Categories:

  • Electricity and Magnetism
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE