Enhancing thermo-hydraulic performance of solar air collectors through three-dimensional airflow using novel artificial roughness designs

Abstract

BackgroundThe solar air collectors involve exploring their design, efficiency, and performance attributes. Common challenges include addressing issues such as small convective heat transfer coefficients between the air and the absorber, which can result to higher absorber plate temperatures and heightened thermal losses. Through the incorporation of artificial roughness onto the collector plate with a suitable design, it is possible to disrupt the shear layer and improve the convective coefficient. MethodsThis study focuses on hydrodynamic and thermal analyses to identify optimal chicane shapes and arrangements, such as CTPrism, CRRec, and CR, planted on the bottom wall of a solar air collector. Thermo-hydraulic performances are investigated using comprehensive CFD simulations, validated by experimental data and comparing them to smooth ducts. Significant findingsIn this work, a novel hydrodynamic and thermal analysis is introduced, demonstrating that the utilization of (CTPrism) shapes arranged in a staggered configuration leads to a significant enhancement of 68 % in heat transfer and 95 % in turbulent intensity. Consequently, there is an improvement in thermo-hydraulic performance, reaching up to 2.39, while still maintaining moderate friction losses.