EVAPORATIVE HYDROPHILIC SURFACE FOR A HEAT EXCHANGER, METHODOF MAKING THE SAME AND COMPOSITION THEREFOR

摘要

A heat exchanger/evaporator for transferring heat from a first heat exchange fluid to a liquid to be evaporated into a gaseous second heat exchange fluid that includes a thermally conductive element (30) separating a first flow pa th (34) for the first heat exchange fluid and a second flow path (36) for the second heat exchange fluid. A first sur~face is on the element (30) in heat exchange relation with the first flow path (34) and a second surface is on t he element (30) opposite the first surface and is in heat exchange relation wit h the second flow path (36). A hydrophilic coating (50) is bonded on part of t he second surface and includes a powder of nominally spherically shaped particl es including nickel, chromium, aluminum, cobalt and yttrium oxide bonded togeth er with a braze metal predominantly made up of nickel, chromium and silicon and diffused into the nominally spherically shaped particles and the second surface. Also disclosed is a composition useful in forming a hydrophilic surface and a method of making a heat exchanger/evaporator.