Analytical study of flow and heat transfer in cross and non-cross flow jet plate solar air heater

Abstract

Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.

This paper presents an analytical study of flow and heat transfer in cross and non - cross flow solar air heater for inline and staggered plates inserted between absorber and bottom plates. Results are presented for various parameters of cross and non - cross flow such as pitch to hole diameter of the jet plate (X / D = 6.0 – 10.0), height of the upper channel to hole diameter (Z1 / D = 6.0 – 10.0), height of the lower channel to hole diameter (Z2 / D = 8.0 - 14.0), Reynolds number (Re = 3000 - 43000), In this study, heat transfer coefficient, outlet temperature of air, collector efficiency and friction factor are calculated for the above parameters. In a cross - flow inline hole jet plate solar air heater, the considerable increment in collector efficiency has been found from 15.68 to 54.88% for m1= 50 – 300 kg / hm², X / D = 6.0 - 10.0 and N = 561 whereas the value of heat transfer coefficient is increased from 3.24 to 8.40 W/m²K for X / D = 6.0 - 10.0 and m1= 50 kg/hm² which is higher than cross - flow staggered hole and non - cross flow inline/staggered hole jet plate solar air heater. The Nusselt number (Nu) increase with decrease in jet hole diameter (D) for fixed mass flow rate.