IDEA #9UTSB2 Heat Pipes Capillary Structures For Solar Receivers

HEAT PIPES CAPILLARY STRUCTURES FOR SOLAR RECEIVERS Description Concentrating solar power plants produce electric power by converting the sun's energy into high-temperature heat using various mirror configurations. The heat is then channelled through a conventional generator. The plants consist of two parts: one that collects solar energy and converts it to heat, and another that converts heat energy to electricity. A concen- trator, is the primary solar component of the system. The dish structure must track the sun continuously to reflect the beam into the thermal receiver. The thermal receiver is the interface between the dish and the engine/generator. It absorbs the concentrated beam of solar energy, converts it to heat, and transfers the heat to the engine/generator. Alternate thermal receivers are heat pipes wherein the boiling and condensing of an intermediate fluid is used to transfer the heat to the engine. Improvement of design of heating zone by use of high temperature heat pipe allows to enlarge the total efficiency by 2-5%. The National Technical University of Ukraine (NTUU “KPI”) has addressed solar receiver heat pipe problems and has developed a new technology of heat pipe wicks fabrication allowing the process of capillary system formation and applying to a substrate. Innovative Aspect and Main Advantages The team has worked out a novel solar receiver capillary struc- ture design. The technology of wick applying to concave and convex surface of the solar receiver heat exchange elements is one of key questions for reliability of operation. Uniform mechanical contact between wick and substrate, uniform and specified wick properties are obligatory technical require- ments to wick structures for solar receivers. NTUU “KPI” has concentrated fabrication techniques for concave cylindrical and convex spherical surfaces. Typical parameters for cylinders are: length 470 mm, tube inner diameter 73 mm; for spherical segments are: curvature radii 177 mm and 244 mm, 70-degree half angle. The improvement and optimization of wick designs and study of heat/mass transfer processes inside of porous media of solar receiver had supplemented a technological part. Areas of Application Transformation of solar energy into electricity in areas with good solar resources, limited fossil fuel supplies, and no power distribution network. its efforts on developing wick to automate GENERATOR Fig.1 Concentrating solar power system with the use of a sodium cooling fluid. Dome #1, R177 appearance Dome #1, R244 appearance Fig.2 A new type of capillary system (Solar Heat Pipe Wicks) for sodium evaporation, made of discrete metal fibers. Stage of Development Samples of heat pipe heating zone for a stirling machine, development of technology of capillary system fabrication with spherical, flat and cylindrical surface are transferred to Sandia National laboratories, DOE USA . Contact Details The National Technical University of Ukraine "Kyiv Polytechnical Institute", Kyiv Contact person: Volodymyr Baturkin Phone: (380) 044 241-75-97; +380675038220 Fax: (380) 044 241-75-97; E-mail: baturkinvm@mail.ru