International Journal of Engineering Research in Electronics and Communication Engineering

CFD and Experimental Studies of Heat Transfer and Pressure Drop in a Tube Equipped With Drilled Twisted Tape Inserts

Author : Sagar V Patil ¹ Prof.. D.G. Kumbhar ²

Date of Publication :7th June 2016

Abstract: The present report focused on CFD and Experimental study of heat transfer, friction factor and Performance Evaluation Criteria(PEC) of tube in tube type heat exchanger fitted with drilled twisted tape inserts. The inner and outer diameters of the tube are 20mm and 40mm respectively and cold and hot water are used as a working fluid in shell and tube side,. The tapes are inserted in a tube at three different twist ratio(y) of(2.5, 3.33, 5) having 45mm, 60mm and 90mm pitch. The drilled twisted tape are having a drilled holes of 5mm and 8mm along the pitch of the tape. The result obtained from tube with plain twisted tape inserts, and drilled tape inserts are compared with the plain tube, within the Reynolds number range from 3223.6 to 22344.05.CFD simulation was also performed on a plain tube by using standard k-e and sst-k-w model.. Sst-k-w model was selected for further studies as it is more reliable model and also provides more accurate prediction of flow separation and also in the present work the enhancement in heat transfer rate matches with the sst-k-w model when compared with that of standard k-e model for the experimental reading of plain tube. The experimental as well as simulation results shows that both the heat transfer rate and friction factor in a tube equipped with twisted tape inserts as well as drilled tape inserts were significantly higher than the plain tube, Over the range of Reynolds number investigated, Based on thermal performance factor for plain twisted tape 90mm pitch tape gives maximum ?th as compared with 45mm and 60mm pitch. And for drilled tape inserts both 5mm and 8mm drilled tapes provides the maximum ?th with 90mm pitch tape, over the provided set of Reynolds number value.

Reference :

1. A.E Bergles, in: W.M. Rosennow, et al, (Eds.) Techniques to Augment Heat Transfer reading: Handbook of heat Transfer Application McGraw-Hill, New York, 1985,
2. A E Bergles R L Webb A guide to the literature on convective Heat Transfer Augmentation Adv. Enhanced Heat Transfer
3. Eiamsa-ard K Wongcharee S Sripattanapipat Experimental investigation of heat transfer and friction factor in a circular tube fitted with regular twisted tape Department of Mechanical Engineering, Faculty of Enginnering Mahanakron University of technology Bangkok Thialand
4. Xiaoyu Zhang, Zhinchin Liu, Wei Liu
5. Numerical studies on heat transfer enhancement without core rod inserts school of energy and power Engineering Huazhong University of science China
6. S R Shabanian, M Rahimi , M. Shahhosseini, A.A Alsairafi: CFD analysiCFD Research center, Chemical Engineering Department, Razi University, Iran faculty of mechanical Engineering, college of Engineering and petroleum Kuwait university, Kuwait