Radiation Heat Transfer Control by a Porous Layer and Gas Injection

The possibility of radiation heat transfer control by a combined model of an active thermal insulation system and a radiative converter was investigated. A semitransparent porous layer was placed between a high-temperature region and a low-temperature region, and gas was injected through the layer in the positive and negative directions. The mechanism of heat transfer is completely different for the positive and negative mass flux. By changing mass flux of air between-0.1 and 0 kg m^-2s^-1, dimensionless radiative flux at the back face can be controlled between 2×10⁴ and 0.1. In this region, the porous layer behaves as the active thermal insulation system, and the mechanism of the radiation heat transfer control is similar to that of a triode.