Experimental performance analysis of an improved receiver for Scheffler solar concentrator

Abstract

This study presents the experimental analysis of the convex receiver for a Scheffler solar concentrator. The solar receiver with three different arrangements was tested for steam generation. Thermal performance is determined by energy analysis. An analysis of the receiver with the first arrangement revealed approximately 42% heat losses from the bare receiver. Then a convective heat loss is mitigated by providing a cavity on the receiver. However, no significant improvement in thermal efficiency is observed. Further, the tube coil is fixed on the cavity’s inner wall and water circulated through the coil to harvest the maximum energy. The average intensity of solar beam radiation was 638 W/m2 during the experimentation time of 9:00 to 15:00 h. The stagnation test result estimated that 109 W/m2 K overall heat loss coefficient of the receiver. The receiver’s energy efficiency with the first, second, and third arrangements was obtained to be 57.71%, 60.93%, and 68.03%, respectively, under the same operating conditions. In all receiver arrangements, the third arrangement has been found attractive for enhancing the parabolic dish concentrator’s efficiency.