Solar powered air conditioning analysis and performance

The winter heating performance of a wickless heat pipe (Thermosyphon) solar collector for out-door in desert climatic conditions in Egypt is presented. The collector consists of three Thermosyphons having identical equal length, 2 (m) and of different outer diameters (OD);which are 28.6,22.2 & 19 (mm). Three pairs of finned plates of the samesurface area have been attached to the three pipes, to enhance the solarabsorbing surface. Refrigerant Rll has been used as the working fluid.Temperature distribution profiles at different circumferential sections alongthe pipe longitudinal axis have been measured and drawn for eachThermosyphon to determine the maximum heat capacity. The effects of both the unsteady heat flux at the evaporator section and the intermettentcooling at the condenser section of the heat pipes on the collectorefficiency have been investigated. The heat capacity and hence thermalefficiency are found to be in direct proportion to the pipe diameter for thebiggest and middle diameter pipes. A state of functioning failure (burn-out) has been attained with the smallest diameter Thermosyphon. It isconcluded, also, that the wickless heat pipe solar collector overcomesmost of the disadvantages of the common direct solar collectors.