- Author
- Pope, R. B. | Parker, J. A.
- Title
- Analysis of Ablation Products and Boundary-Layer Chemistry of Ablating Materials With a Mass Spectrometer.
- Coporate
- NASA Ames Research Center, Moffett Field, CA
- Report
- NASA-TM-X-60482, 1967, 25 p.
- Distribution
- Available from National Technical Information Service
- Keywords
- mass spectrometers | ablation products | boundary layers | ablative materials | teflon | chemical analysis | high temperature environments | pyrolysis differential thermal analysis | decomposition products | supersonic combustion | chemical chain reactions | chain reactions | thermal analysis
- Abstract
- The prediction of ablative heat shield performance during atmospheric entry requires a description of the chemical reactions taking place in both the organic solid and the adjacent boundary-layer gas flow. These reactions are coupled so that, during ablation, part of the incident heat flux (convective and radiative) is dissipated in endothermic pyrolysis reactions, part of the convective heat flux is blocked by the transfer of gaseous ablation products into the boundary-layer flow, and the convective heat flux may lso be modified by chemical reactions of the ablative species in the boundary-layer flow. The degree of blockage and also the modification in heating from the boundary-layer chemical reactions depend, in part, upon the numbers and kinds of species transferred.