VERY HIGH TEMPERATURE HEAT EXCHANGER

摘要

A high temperature fluid-to-fluid heat exchanger (10) is described wherein heat is transferred from a higher temperature fluid flow core region (75) to a lower temperature fluid flow annulus (50). The wall (54) separating the high and low temperature fluid flow regions is comprised of a material having high thermal absorptivity, conductivity and emissivity to provide a high rate of heat transfer between the two regions. A porous ceramic foam material (60 ) occupies a substantial portion of the annular lower temperature fluid region (50), and is positioned to receive radiated heat fr om the wall (54). The porosity of the ceramic foam ma- terial (60) is sufficient to permit a predetermined relatively unrestricted flow rate of fluid through the lower temperature fluid flow region (50).