Investigation of the Influence of the Improved Isolation of SiC and C-SiC Plates on the Heat Flux Distribution.

Kurzfassung

Gas surface interaction phenomena in a high enthalpy flow field are strongly influenced by the catalytic activity of the surface. A water-cooled flat plate which allows to mount ceramic materials on it has been used in LBK. But heat losses from the ceramic materials to the water-cooled part of the plate dominates the catalytic effects and makes it difficult to study their influences on the heat flux rate. SiC and C-SiC materials were mounted on the flat plate using a teflon isolation and tests were performed at two different angles of attack. The isolation reduced the heat losses and improved the temperature distribution on the surface remarkably. Surface temperatures were measured by means of an IR camera and a spectral pyrometer. Pitot pressure distribution and cold wall heat flux rates were measured and compared with numerical results using a quasi one-dimensional code including chemical non-equilibrium phenomena. Axial pressure and heat flux distribution on the flat plate were determined.