High Efficiency Parabolic Solar Collector with Glass Pipe and Black Fluid

摘要

Glass pipe and a black fluid were combined with a parabolic solar reflector to produce a high efficiency solar collector. The thermal efficiency of three different types of receivers with a parabolic trough solar reflector were compared: (1) single-layered glass tube with black fluid, (2) double-layered glass tube with black fluid, and (3) black copper tube with clean water. The single-layered glass tube employing a black working fluid performed better than the other types. The efficiency of the single-layered glass tube with black fluid was found to be about 3% better than the black copper tube. The effect of mass flow rate (laminar or turbulent flow) was found to be insignificant. The black fluid solar collector was found to have an optimum efficiency for a blackening agent concentration of about 15 ml per gallon of water. An analytical model was developed to compare with the experimental data by using a lumped heat capacity formulation. (ERA citation 09:049704)