Accession Number : AD0660533

Title :   EFFECT OF INCOMPLETE ENERGY ACCOMMODATION ON FREE-MOLECULE RECOVERY TEMPERATURE,

Corporate Author : AEROSPACE CORP EL SEGUNDO CALIF LABS DIV

Personal Author(s) : Epstein,Melvin

Report Date : SEP 1967

Pagination or Media Count : 36

Abstract : A model of the wall boundary condition in kinetic theory is described and applied to the analysis of the recovery temperature of a circular cylinder placed transverse to a free-molecule stream. This model, more sophisticated than its predecessor, is constructed to allow the description of the non-monotonic variation of thermal accommodation coefficient with gas energy which has been predicted by elaborate theoretical investigations and has been observed experimentally. The model is found to fit all of the available recent experimental data for thermal accommodation coefficients for rare gases on tungsten. The use of this model to predict free-molecule recovery temperatures reveals a pronounced effect of incomplete accommodation on the relationship between recovery temperature and flow Mach number. This has important implications regarding the interpretation of flow field measurements made with a free-molecule recovery temperature probe. (Author)

Descriptors :   (*RAREFIED GAS DYNAMICS, *THERMODYNAMICS), BOUNDARY LAYER, KINETIC THEORY, HEAT TRANSFER, TEMPERATURE, RECOVERY, FLOW FIELDS, TUNGSTEN, MATHEMATICAL MODELS, CYLINDRICAL BODIES, SURFACES, ENERGY

Subject Categories : Aerodynamics
      Fluid Mechanics
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE