Reflux Heat-Pipe Solar Receiver for a Stirling Dish-Electric System

摘要

The feasibility of competitive, modular bulk electric power from the sun is enhanced by the use of a reflux heat-pipe receiver to combine a Stirling engine with a paraboloidal dish concentrator. This combination represents a potential improvement over previous successful demonstrations of Stirling dish-electric technology in terms of enhanced performance, lower cost, and longer life. In the reflux (i.e. gravity assisted) heat-pipe receiver, concentrated solar radiation causes liquid sodium to evaporate, the vapor flows to the Stirling engine heaters where it condenses on the heater tubes. The condensate is returned to and distributed over the receiver by gravity (refluxing) and by capillary forces in a wick lining the receiver. It is essentially an adaptation of sodium heat pipe technology to the peculiar requirements of concentrated solar flux and provides many potential advantages over conventional tube receiver technology. This paper describes the preliminary design of a reflux heat-pipe solar receiver to match the STM4-120 variable swashplate Stirling engine to a Test Bed Concentrator at Sandia National Laboratories Distributed Receiver Test Facility. Performance analysis and other design considerations are presented and discussed. (ERA citation 12:036658)