Experimental Investigation of Heat transfer and Friction Factor Characteristics with Triangular-cut Twisted Tape (TCTT) Inserts

Abstract

An experiment was conducted to investigate the heat transfer characteristics and friction factor characteristics of a concentric tube fitted with triangular-cut twisted tape (TCTT) insert with a twist ratio Y of 5.4 and depth of triangular cut of 1.2 cm, which were studied for laminar flow. This investigation also is used to find the heat transfer coefficient, Nusselt number and Reynolds number. The heat transfer enhancement was caused with the flow of fluid between the plain twisted tapes and TCTT. The experimental value of plain tube and triangular-cut twisted tube obtained from the experimental work and these two statistical data were compared with the results. The results show that the enhancement of heat transfer rate induced with plain and TCTT inserts increases with the increase in Reynolds number. The Reynolds numbers were varied in the range of 5710–18,366. The Reynolds number in the tube with triangular- cut twisted tape insert were enhanced by 1.1–1.3 times compared with smooth twisted tape inserts. The configuration of TCTT insert offered higher heat transfer rate and friction factor than that of the plain twisted inserts.