Experimental and numerical characterization of a steady-state cylinderical balckbvody cavity at 1100 degrees celsius

摘要

A blackbody calibration furnace at the NASA Dryden Flight Research Center is used to calibrate heat flux gages. These gages are for measuring the aerodynamic heat flux on hypersonic flight vehicle surfaces. The blackbody is a graphite tube with a midplane partition which divides the tube into two compartments (dual cavities). Electrical resistance beating is used to heat the graphite tube. This heating and the boundary conditioins imposed on the graphite tube result in temperature gradients along the walls of the blackbody cavity. This paper describes measurements made during steady-state operation and development of finite-difference thermal models of the blackbody furnace at 1199 deg C. Two configurations were studied, one with the backbody outer surface insulated and the other without insulation. The dominant modes of heat transfer were identified for each confiruation and the effect of variations in material properties and electric current that was passed through the blackbody were quantified.