Accession Number : AD0746805

Title :   Microwave Measurements of Flow Field Characteristics at the Stagnation Point of a Blunt Reentry Body,

Corporate Author : AIR FORCE CAMBRIDGE RESEARCH LABS L G HANSCOM FIELD MASS

Personal Author(s) : Rotman,Walter

Report Date : 1972

Pagination or Media Count : 10

Abstract : Plasma diagnostic sensors, including microwave antennas and electrostatic probes, are used to measure the flow fields at the stagnation point of a blunt nose cone during atmospheric reentry. The microwave measurements determine signal attenuation, reflection coefficient, and mutual antenna coupling as a function of altitude. The flight data are compared with calculations of flow field ionization and antenna performance, based upon three competitive flow field models. Excellent agreement is obtained at high altitudes only for that flow field model which includes both viscous interaction across the entire shock layer and vibrational nonequilibrium effects. These results are further confirmed by comparison with probe data and observations from another flight program. (Author)

Descriptors :   (*PLASMA SHEATHS, MEASUREMENT), (*REENTRY VEHICLES, TELEMETERING ANTENNAS), BLUNT BODIES, ATMOSPHERE ENTRY, STAGNATION POINT, FLOW FIELDS, IONIZATION, BLACKOUT(PROPAGATION), ELECTRON DENSITY

Subject Categories : Plasma Physics and Magnetohydrodynamics
      Unmanned Spacecraft

Distribution Statement : APPROVED FOR PUBLIC RELEASE