Volume 11 Issue 1 ( March )

The solar air heater (SAH) harnesses solar energy and finds widespread application in various contexts, including drying agricultural products, heating spaces in buildings, etc. However, the viability of SAH has a problematic issue due to its low performance, which limits its applicability in actual applications. In this work, two distinct novel turbulators; namely, S- shape and Airfoil (NACA0018) turbulator have designed to take advantage of their flow structures to get enhanced performance of SAHs. The thermal analysis of rectangular SAH with a combination of S-shape and Airfoil (NACA0018) shape turbulators performed numerically. The operating and geometric parameters are : relative pitch (P/e) varied from 8 to14, angle of attack (α) varied from 0°-45°, and Reynolds number (Re) varied from 4000-16000. Both heat transfer and friction factor characteristics of SAH with turbulators show a significant improvement over smooth SAH. The maximum value of thermos-hydraulic performance is 2.21 which has been achieved at P/e=12, Re=12000 and α=30º. The exergetic analysis was also conducted, yielding a maximum exergetic efficiency of 2.25%.

Keywords: Rectangular Channel; S-shape and Airfoil turbulators; CFD; Thermo-hydraulic performance; Exergetic Performance