Statistical analysis was employed to investigate heat transfer rate and thermal effectiveness of solar air heater (SAH) featuring V shaped ribs. The addition of square roughness in form of inclined ribs at a 30° angle was assessed for enhancing thermal efficiency of SAH. In the experimental setup, rib pitches of 15 mm and 20 mm were employed on upper surface of absorber plate. The heat transfer rate for 20 mm rib pitch was analyzed for comparison purposes. Several geometric characteristics of the solar duct were calculated numerically to optimize the maximum rate of heat transfer. The experimental design with a 15 mm rib pitch achieved a peak efficiency of 44.2 %, while model with a 20 mm rib pitch reached a peak efficiency of 41.4%. Both models exhibited an efficiency increase of 4.37% compared to a smooth absorber surface. First model gives the maximum absorber plate and glass cover temperatures at surface during solar intensity ranging from 1150 to 1250 W/m2 between 12:30 PM and 1:30 PM. An exergy analysis comparison indicated that exergy value rises with increasing solar intensity throughout day. Computational Fluid Dynamics (CFD) analysis was conducted to validate the experimental findings and explored flow singularities above absorber surface.