Solar-heated-air receivers

Abstract

Receiver design alternatives for a central tower, heat-air receiver of a solar/gas turbine electrical generation plant are considered. Apertured and unapertured, domed-surface and -cavity receivers are examined and losses such as incident flux reflection and reradiation from the receiver are included. The receiver, constructed of ceramic domes that are individually cooled by impingement-jet heat-transfer techniques, is designed to supply heated air at 1800°F and operate in a pressurized condition at a pressure ratio of four. It is shown that high thermal conversion efficiencies (80–90%) may be achieved with cavity receivers where the interior cavity surfaces are formed from single or multiple domes. The efficiencies of surface receiver elements are found to be substantially less than those of cavities, from 54 to 70 per cent. The difference lies in the higher reradiation flux losses of surface receivers.