Accession Number : ADA307035

Title :   Analysis of Surface Ablation of Noncharring Materials with Description of Associated Computing Program.

Descriptive Note : Technical note,

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION MOFFETT FIELD CA AMES RESEARCH CENTER

Personal Author(s) : Matting, Fred W. ; Chapman, Dean R.

PDF Url : ADA307035

Report Date : DEC 1966

Pagination or Media Count : 82

Abstract : A generalized method is presented for solving the problem of stagnation point heat transfer and material response for blunt bodies experiencing melting and vaporizing or subliming ablation. The analysis is applicable to wind-tunnel and flight conditions (with body forces taken into account); internal radiation can be considered or the material can be assumed opaque; the analysis can be used for different planets. During entry flights, a body will start in the free-molecule regime, pass through a transitional regime, and finish in the continuum regime of gas dynamics. Approximate equations, rationally obtained, are presented which provide bridges between the free- molecule and continuum regimes for such quantities as the convective heating rate, surface shear, heat blockage, and mass loss. Several illustrative examples (including surface chemical reaction cases) show the applications of the analysis. Comparisons with experiment are made where possible. The analysis has been machine programmed for numerical solutions using a finite difference scheme, and a running energy balance is kept as a check on accuracy. Instructions are provided for using the computing program.

Descriptors :   *REENTRY VEHICLES, *GUIDED MISSILES, *SPACECRAFT, *HEAT SHIELDS, *CHARRING, SHEAR PROPERTIES, HEAT TRANSFER, COMPUTER PROGRAMS, ABLATION, ATMOSPHERE ENTRY, GAS DYNAMICS, FINITE DIFFERENCE THEORY, MELTING, SURFACE REACTIONS, CONVECTION(HEAT TRANSFER), BLUNT BODIES, BRIDGES, HEAT RESISTANT MATERIALS, VAPORIZATION, STAGNATION POINT.

Subject Categories : Guided Missile Reentry Vehicles
      Thermodynamics
      Unmanned Spacecraft
      Manned Spacecraft

Distribution Statement : APPROVED FOR PUBLIC RELEASE