Experimental study of heat transfer coefficient with rectangular baffle fin of solar air heater

Abstract

This paper presents an experimental analysis of a single pass solar air collector with, and without using baffle fin. The heat transfer coefficient between the absorber plate and air can be considerably increased by using artificial roughness on the bottom plate and under the absorber plate of a solar air heater duct. An experimental study has been conducted to investigate the effect of roughness and operating parameters on heat transfer. The investigation has covered the range of Reynolds number Re from 1259 to 2517 depending on types of the configuration of the solar collectors. Based on the experimental data, values of Nusselt number Nu have been determined for different values of configurations and operating parameters. To determine the enhancement in heat transfer and increment in thermal efficiency, the values of Nusselt have been compared with those of smooth duct under similar flow conditions.

Key words： Nusselt number; flow rate; heat transfer; heat transfer coefficient; thermal efficiency; forced convection

Acknowledgments

The authors would like to thanks: Mr. Saber Guenifi, Dr. A. Brima and Dr. D. Bensahal for helpful counseling. This study corresponding to laboratory of LGM (Laboratoire de Génie Mécanique de l’université Mohamed Khider de Biskra).

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