Experimental investigation of heat transfer and pressure drop for fin-and-tube heat exchangers with large-row and large-diameter tubes

Heat transfer and flow friction characteristics of fin-and-tube heat exchangers were experimentally investigated in this study, and heat exchanger performances were additionally evaluated based on the three criteria of identical mass flow criteria, identical pressure drop criteria and identical pumping power criteria, respectively. The tested heat exchangers consist of five twelve-row heat transfer surfaces such as plain fin (PF), slit fin (SF), fin with longitudinal vortex generator (LVGF), mixture fin of SF and LVGF (MF), and spiral fin (SPF). Under the three criteria, SPF heat exchanger represents lowest performance than the other four heat exchangers, and MF heat exchanger represents better performance than that of LVGF while at high Reynolds number region SF heat exchanger provides the best performance. The heat transfer and friction factor correlations have been obtained in a wide range of Reynolds numbers, which are referred for further fundamental research and engineering applications.