Fluid flow characteristics of the hybrid broken W-shaped with arc ribbed collector in the flow regime of rectangular duct under turbulent flow

• Novel Hybrid Geometry of broken W-shaped with arc rib for flow disruption. • Optimal ( THP = 1.14) was achieved at a ( d/w ) of 0.30, (Re) of 10,200. • Significant Nusselt number augmentation ratio ( Nuₙ/Nuₛ ) of 1.719. • Correlation Development for ( R ) and ( G' ). The thermal performance of flat plate solar air heaters (SAHs) is limited by the lower thermal performance. In the present study the absorber plate is modified by novel preparation of artificial ribs as 3D hybrid broken W-shaped with arc ribs over the absorber plate. A 3D computational analysis is carried out in the Renormalization Group (RNG) k-ε turbulence model in ANSYS Fluent 2021 R2 to examine the impact of varying the various ranges of relative gap positioning (d/w) of hybrid broken W-shaped with arc ribs on the average Nusselt number (Nu), friction factor (fr), and thermo-hydraulic performance (THP), turbulent kinetic energy (TKE), pressure drop across the test section which is subjected under a uniform heat flow of 1000 W/m 2 , (Re) ranging from 3000 to 22000 and the relative gap positioning (d/w) are varied for a range of 0.15, 0.30, 0.45, 0.60, 0.75 while keeping fixed attack angle (β) at 60 o , arc angle (α) at 30 o , relative rib height (e/D h ) fixed at 0.043, relative roughness pitch (P/e) of 10, G d /L v of 0.67, with a rib height element of 3 mm. The highest enhancement in the Nusselt number augmentation ratio (Nu r /Nu s ) and friction factor augmentation ratio (fr r /fr s ) is noticed as 1.719 times that of smooth plate of SAH at d/w of 0.30 at Re of 10200, and 3.50 times that of smooth plate of SAH at d/w of 0.15 at Re of 10200. Results show that the highest value of (THP) of 1.14 at d/w of 0.30 and Re of 10200.