Accession Number : AD0702435

Title :   A DISCUSSION AND ANALYSIS OF SOME ASPECTS OF TRANSPIRATION COOLED NOSETIPS.

Descriptive Note : Technical rept. Jun-Sep 69,

Corporate Author : AEROSPACE CORP SAN BERNARDINO CALIF SAN BERNARDINO OPERATIONS

Personal Author(s) : Gater,R. A.

Report Date : 22 OCT 1969

Pagination or Media Count : 46

Abstract : Transpiration cooling of a porous nosetip of a hypersonic reentry vehicle employing water as a coolant is considered. Fundamental problem areas are discussed, and those requiring considerably more analytical and/or experimental investigation are noted. Analysis and example calculations are presented for the local rate of mass transfer from the liquid surface film to the proximate gas stream. Particular emphasis is placed upon evaluating the relative importance of the mass transfer contributions due to evaporation from an idealized smooth film surface, additional evaporation due to the 'effective' roughness of the film surface; and entrainment of bulk liquid from the film surface due to shear interaction with the gas flow. Correspondingly, computed results for downstream cooling effectiveness are presented for hypersonic reentry type flow conditions. In addition, analyses are developed and example calculations are presented for film surface temperature, mean film thickness, and mean film surface velocity. Finally, some specific recommendations are made for future research effort. (Author)

Descriptors :   (*REENTRY VEHICLES, AERODYNAMIC HEATING), (*FILM COOLING, EXPERIMENTAL DESIGN), ATMOSPHERE ENTRY, PLASMA SHEATHS, STAGNATION POINT, MASS TRANSFER, WATER, SKIN FRICTION, EVAPOTRANSPIRATION, ENTHALPY

Subject Categories : Air Condition, Heating, Lighting & Ventilating
      Guided Missile Dynam, Config & Cntrl Surfaces
      Guided Missile Reentry Vehicles

Distribution Statement : APPROVED FOR PUBLIC RELEASE