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. (De Posamentier)
An irreversible thermodynamics model for graphite sublimation in intense radiation environments
Irreversibles thermodynamisches Modell der Graphitsublimation unter dem Einfluss hoher Waermestrahlungen
AIAA-Papers ; 1-9
1978
9 Seiten, 8 Bilder, 1 Tabelle, 24 Quellen
Conference paper
English
Graphite sublimation under low and high convective mass transfer environments
Tema Archive | 1976
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