Experimental study of passive heat transfer enhancement technique by using twisted tape insert inside a tube in tube heat exchanger

Abstract

Heat transfer augmentation techniques are used in heat exchanger systems in order to enhance heat transfer & improve
thermal performance. There are various methods to enhance the performance of heat transfer devices such as treated surface, rough
surfaces as well as incorporations of insertssuch as tabulators & swirl flow devices. My project focuses on reviewing the passive
methods in heat pipe exchanger. The passive heat transfer augmentations,external power source input is not required.For the efficient
heat transfer,two parameters are very important 1.Increase the surface area 2.Resistance time of the heat transfer fluid.These passive
methods is based on the principle,by applying various techniques increase the effective heat transfer area,resistance time &
consequently heat transfer coefficient.So that enhancement of convective heat transfer takes place in tube in tube heat exchanger.For
that enhancement technique the expected outcome is done by using twisted tape insert inside a tube in tube heat exchanger.The
expected outcome is to find the effects of the Typical Twisted tapes (TT) on the heat transfer enhancement and friction factor
behaviors in turbulent flow regimes (5000 ≤ Re ≤ 17,100) are described. The Typical twisted tape, twisted tapes with different twist
ratio (y/w=2.5, 3 and 3.5) are tested using the water as the working fluid