Accession Number:

ADA089405

Title:

An Irreversible Thermodynamics Model for Graphite Sublimation in Intense Radiation Environments.

Descriptive Note:

Final rept.,

Corporate Author:

AEROSPACE CORP EL SEGUNDO CA VEHICLE ENGINEERING DIV

Personal Author(s):

Report Date:

1980-09-15

Pagination or Media Count:

37.0

Abstract:

A model for the phase change behavior of graphite when exposed to a high external radiation heat flux has been developed in order to examine solid-gas nonequilibrium effects. The usual Knudsen-Langmuir type model is extended to one which allows both pressure and temperature discontinuities at the ablating surface. Calculated results indicate a relatively constant effective heat of ablation. However, major uncertainties are shown to remain regarding individual carbon species concentrations and the input energy required for melting. A unique feature of the irreversible thermodynamics model is the prediction of gas phase supersaturation when JANNAF thermochemical data is utilized. Author

Subject Categories:

  • Physical Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE