Accession Number : AD0766206

Title :   Comparison of the Effects of Different Transport Coefficients on the Nonlinear Reflection and Transmission Coefficients of a Reentry Plasma.

Descriptive Note : Physical sciences research papers,

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

Personal Author(s) : Papa,Robert J. ; Taylor,Richard L.

Report Date : 08 JUN 1973

Pagination or Media Count : 52

Abstract : In a previous report, it was explained how it is desirable to maximize the amount of power that can be transmitted from a reentry vehicle by suppressing the onset of antenna voltage breakdown. Thus, the amount of high power EM radiation that can be transmitted will be greatly enhanced if electrophilic compounds are injected into the reentry flow field. A computer program has been set up and is now capable of numerically integrating Maxwell's equations coupled with the plasma transport equations. The computer code calculates the electron density profile and the plane wave transmission and reflection coefficients, as a function of incident power level for a variety of reentry flow field conditions. An implicit-explicit method is used to numerically integrate in time the coupled, nonlinear, parabolic partial differential equations. A very efficient algorithm is given for solving the coupled, tridiagonal system of equations for the electron and positive ion densities. For a typical set of reentry flow field conditions, graphs are presented of the electron density profile and the plane wave reflection and transmission coefficients for different incident power levels. The effects of varying the plasma transport coefficients are investigated in some detail. Also, the effects of varying the length of a high power pulse are investigated. (Author)

Descriptors :   (*PLASMA SHEATHS, *ELECTRON DENSITY), (*ATMOSPHERE ENTRY, *BLACKOUT(PROPAGATION)), MICROWAVES, PARTIAL DIFFERENTIAL EQUATIONS, RECOMBINATION REACTIONS, NUMERICAL INTEGRATION, NUMERICAL ANALYSIS, COMPUTER PROGRAMMING, WAVE PROPAGATION

Subject Categories : Plasma Physics and Magnetohydrodynamics
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE