DESIGN AND CONSTRUCTION OF A SOLAR-POWERED FLUIDYNE TEST BED

Liquid piston Stirling engines (sometimes termed "fluidynes") have been studied extensively and applied in a variety of energy conversion applications. They are attractive for low capital costs and simplicity of construction. In addition, their operation as external combustion engines allows for flexibility in primary energy sources which is a distinct advantage when a low-cost or free source of heat can be paired with their minimal construction costs. Disadvantages of these devices include relatively low efficiency and low power density. A solar-powered fluidyne test bed was constructed and operated at the University of Colorado at Colorado Springs. This test bed was composed of a fluidyne engine which was constructed from copper pipe and plastic tubing along with temperature and pressure instrumentation. The system was designed to be powered by a Fresnel lens concentrating solar energy. The concentrated solar energy from the Fresnel lens provided ample power to operate the test bed, and tests were run in a wide variety of conditions. Indicated work of this unloaded engine was shown to agree well with a simple theoretical model of a Stirling cycle.