Accession Number : ADA306852

Title :   Effect of the Chemical State of Pyrolysis Gases on Heat-Shield Mass.

Descriptive Note : Technical note,

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION HAMPTON VA LANGLEY RESEARCH CEN TER

Personal Author(s) : Brewer, William D. ; Stroud, C. W. ; Clark, Ronald K.

PDF Url : ADA306852

Report Date : DEC 1968

Pagination or Media Count : 28

Abstract : Results are presented from an analytical investigation to determine the effect of the chemical state of the pyrolysis gases on the heat-shield mass required for a reentry vehicle in a given environment. Mass per unit area of ablative material required is calculated for a number of constant-heating-rate environments and the total mass is calculated for a lifting-body vehicle in a typical reentry trajectory. The required mass of ablative material is calculated for three different assumptions: (1) The pyrolysis gases are in chemical equilibrium at all times, (2) the gases are chemically frozen at 500 deg K, and (3) the gases change from the frozen state to equilibrium over some temperature range. p3

Descriptors :   *MASS, *GASES, *CHEMICAL REACTIONS, *HEAT SHIELDS, *PYROLYSIS, *ABLATIVE MATERIALS, REENTRY VEHICLES, TEMPERATURE, ATMOSPHERE ENTRY, FREEZING, TRAJECTORIES, CHEMICAL EQUILIBRIUM.

Subject Categories : Physical Chemistry
      Inorganic Chemistry
      Thermodynamics
      Astronautics

Distribution Statement : APPROVED FOR PUBLIC RELEASE