Investigation of Fluid Flow and Heat Transfer in Porous Matrices for Transpiration Cooling.

摘要

An investigation was conducted to determine the heat transfer and fluid flow characteristics in porous matrices for transpiration cooling. Governing differential equations were derived and solved using realistic boundary conditions. Parameters governing the resulting temperature and pressure distributions in porous matrices were identified. Geometry, transient, and dissociation effects on temperature and pressure distributions were determined. Fluid flow and heat transfer characteristics in two-phase flows and multilayer matrices were also analyzed. Experimentally, 301 test runs were performed to measure the temperature distribution and pressure drops across the porous matrices using air, nitrogen, helium, and water as collants. Satisfactory agreement between calculated and measured temperature profiles was obtained. Information on permeability of porous matrices was derived. Good correlation was accomplished for viscous permeability as a function of porosity. (Author)