Experimental and numerical analysis on the thermal performance of the aluminium absorber

Abstract

The absorber is a vital part of a solar air collector and has a significant impact on the overall efficiency of a solar air heating unit. The objective of this research is to examine and compare the performance of two distinct aluminium absorbers with and without aluminium fins by using experimental and numerical (computational fluid dynamics – CFD) methods. The studies were conducted in Mandalay, Myanmar, which is located at latitude 21.98° N and longitude 96.1° E, during December 2022. A plate absorber solar air collector (PASAC) and finned absorber solar air collector (FASAC) with the same absorber area of 0.889 m2 are compared in terms of their thermal performance. At a mass flow rate of 0.0389 kg/s, the average thermal efficiency, as computed numerically, is 53.5 % for FASAC, and the experimental results show a thermal efficiency of 54.2 %. Similarly, for PASAC, the numerical computation yields an average thermal efficiency of 44.4 %, while the experimental results indicate a thermal efficiency of 47.3 %. The FASAC outperforms PASAC in terms of thermal performance. The improved thermal performance of the double-pass solar air collectors with aluminium-finned absorbers can be advantageous for employment as a drying process unit.

Keywords

• aluminium
• double-pass
• solar air collector
• temperature
• thermal efficiency