Accession Number : ADA317594

Title :   Plasma and Flowfield Induced Effects on Re-Entry Vehicles for L-Band at Near-Broadside Aspect Angles. Volume I. Experimental Measurements Program Summary and Aerothermal Data Analysis.

Descriptive Note : Final rept. Jan 94-Sep 96,

Corporate Author : CALSPAN CORP BUFFALO NY

Personal Author(s) : Chadwick, Kenneth M. ; Boyer, Donald W. ; Andre, Stephen N.

PDF Url : ADA317594

Report Date : SEP 1996

Pagination or Media Count : 122

Abstract : A laboratory measurements program has been performed in the Calspan 96 inch hypersonic shock tunnel which has provided a data base on the effects of the ionized flow field about a reentry vehicle on RF energy propagation. The measurements, performed under laminar flow conditions, provide data on plasma induced phase shift and attenuation of incident (uplink) RF signals for three aspect angles around broadside of the test vehicle, as well as measurements of reflection coefficient of an open ended waveguide antenna and mutual coupling between antennas on the vehicle. Vehicle orientations included combinations of pitch and yaw so as to include the effects of crossflow on the measurements The experiments were performed at an L band frequency, under freestream test conditions of 14,000 ft/sec at an equivalent density altitude of 140 kft. Surface distributions of pressure and heat transfer were measured, as well as profiles of the electron number density through the ionized flow field by means of thin-wire electrostatic probes.

Descriptors :   *IONIZATION, *RADIO INTERFERENCE, *HYPERSONIC FLOW, *SPACECRAFT ANTENNAS, HEAT TRANSFER, EXPERIMENTAL DATA, PLASMAS(PHYSICS), ELECTRON DENSITY, FLOW FIELDS, WIND TUNNEL TESTS, REFRACTION, AEROTHERMODYNAMICS, FREE STREAM, LAMINAR FLOW, UPLINKS, HYPERSONIC WIND TUNNELS, ASPECT ANGLE, BOUNDARY LAYER FLOW, RADIOFREQUENCY PULSES, PHASE SHIFT, CROSS FLOW, SHOCK TUNNELS, L BAND.

Subject Categories : Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE