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Using Computational Fluid Dynamics analysis, thermo-hydraulic performance of a rib roughened solar evacuated tube collector has been evaluated for different relative roughness pitch and mass flow rate values. Half portion of absorber tube is roughened and heated uniformly with a heat input of 1000 W/m2. The investigated roughness geometry parameters include relative roughness pitch (P/e) of the order 6–12 whereas relative roughness height is having a fixed value of 0.071. Reynolds number was varied from 2500 to 8000. In contrast to a smooth solar evacuated tube collector, Nusselt number and frictional resistance of a roughened solar evacuated tube collector increased by 1.88 and 2.89 times respectively. Thermo-hydraulic performance parameter of roughened solar evacuated tube collector was found to be 1.36 corresponding to Reynolds number and P/e values of 8000 and 10 respectively which indicates considerable benefit of applying rib roughness in a solar evacuated tube collector. 1. Developed artificially roughened evacuated tube collector solar air heater. 2. Achieved maximum enhancement of order 1.88 times for Nusselt number. 3. Achieved maximum value of 1.36 for thermo-hydraulic performance parameter. [ABSTRACT FROM AUTHOR]