@ARTICLE{Kumar_Dhananjay_Performance_2020, author={Kumar, Dhananjay and Prasad, Laljee}, volume={vol. 41}, number={No 3}, journal={Archives of Thermodynamics}, pages={125-143}, howpublished={online}, year={2020}, publisher={The Committee of Thermodynamics and Combustion of the Polish Academy of Sciences and The Institute of Fluid-Flow Machinery Polish Academy of Sciences}, abstract={Artificial roughness has been found to enhance the thermal performance from the collector to air in the solar air heater duct. This paper presents the results of experimental investigation on thermal performance of three sides solar air heater roughened with combination of multiple-v and transverse wire. The range of variation of system and operating parameters is investigated within the limits of relative roughness pitch of 10−25, relative roughness height of 0.018−0.042, angle of attack of 30°−75° at varying flow Reynolds number in the of range of 3000−12000 for fixed value of relative roughness width of 6. The augmentation in fluid temperature flowing under three side’s roughened duct is found to be 36.57% more than that of one side roughened duct. The maximum thermal efficiency is obtained at relative roughness pitch of 10 and relative roughness height of 0.042, and angle of attack of 60°. The augmentation in thermal efficiency of three sides over those of one side roughened duct is found to be 46−57% for varying values of relative roughness pitch, 38−50% for varying values of relative roughness height, and 40−46% for varying values of angle of attack.}, type={Article}, title={Performance analysis of three sides solar air heater having roughness elements as a combination of multiple-v and transverse wire on the absorber plate}, URL={http://journals.pan.pl/Content/117614/PDF/06_paper.pdf}, doi={10.24425/ather.2020.134575}, keywords={Reynolds number, Relative roughness height, Relative roughness pitch, Solar air heater, Thermal efficiency, One side roughened duct, Three side's roughened duct}, }