Experimental Study on Heat Transfer Enhancement in a Circular Tube Fitted

Abstract

Experimental investigation of heat transfer and Reynolds number characteristics of circular tube fitted with Classic type Twisted Tape (CTT), U-cut Twisted Tape (UTT) and V-cut Twisted Tape (VTT) with twist ratios, T.R = 6.82, 5.90, 5.00 were studied. The TT inserts when placed in the path of the flow of fluid, create a high degree of turbulence resulting in an increase in heat transfer rate and pressure drop. The work includes the determination of heat transfer coefficient and Nusselt number characteristics for various twisted tapes such as CTT, UTT and VTT with different twist ratios. The Reynolds number is varied from 5000 to 12000. The experimental results indicate that the tube with the various twisted tape inserts provides considerable improvement of the heat transfer rate over the plain tube. The results were compared and the twisted tape with U-cut profile shows better heat transfer enhancement.