Experimental Study on Thermal Efficiency of Parabolic Trough Collector (PTC) Using Al2O3/H2O Nanofluid

Abstract

Dispersing small amounts of solid nano particles into base-fluid has a significant impact on the thermo-physical properties of the base-fluid. These properties are utilized for effective capture and transportation of solar energy. This paper attempts key idea for harvesting solar energy by using alumina nanofluid in concentrating parabolic trough collectors. An experimental study is carried out to investigate the performance of a parabolic trough collector using Al2O3-H2O based nanofluid. Results clearly indicate that at same ambient, inlet temperatures, flow rate, concentration ratio etc. hike in thermal efficiency is around 5-10 % compared to the conventional Parabolic Trough Collector (PTC). Further, the effect of various parameters such as concentration ratio, receiver length, fluid velocity, volume fraction of nano particles has been studied. The different flow rates employed in the experiment are 2 ml/s, 4 ml/s and 6 ml/s. Volumetric concentration of 0.02%, 0.04% and 0.06% has been studied in the experiment. Surfactants are not introduced to avoid bubble formation. Tracking mode of parabolic trough collector is manual. Results also reveal that Al2O3-H2O based nanofluid has higher efficiency at higher flow rates.