Experimental Investigations in Circular Tube to Enhance Turbulent Heat Transfer Using Various Types of Twisted Tape Insert

Abstract

This work shows the results obtained from experimental investigations of the augmentation of turbulent flow heat transfer in a horizontal tube by means of twisted tape inserts. Six types of twisted types used with total length of 1200mm and diameter of 50mm are considered for experimentation as follows: normal twisted tape regularly spaced twisted tape, triangular-cut twisted tape, rectangular-cut twisted tape,semicircular-cut twisted tape, and drilled twisted tape. The range of Reynolds number extends from 4500 to 23500. Correlations for Nusselt number, friction factor, and enhancement efficiency are developed for each type of twisted tape inserts from the obtained results. It is observed that the enhancement of heat transfer increases as thetype of twisted tape changes from one to six, respectively.