THERMAL SCIENCE

International Scientific Journal

NUMERICAL STUDY ON THE INFLUENCING MECHANISM OF TWISTED RATIO IN OUTWARD CONVEX CORRUGATED TUBES WITH A TWISTED TAPE INSERT

ABSTRACT
Numerical investigations were conducted on flow and heat transfer in an outward convex corrugated tube with various structural twisted tape inserts. The study investigated the influence of twisted ratio on thermodynamic regulation and mechanism in the corrugated tube. The results indicate that Nusselt number in the corrugated tube (Nuc) exceeds those in the corrugated tube and smooth tube by 120-136% and 171-317%, respectively. Meanwhile, the friction factor increases by 148-153% and 476-514%, respectively. The best overall thermal performance (h = 1.97) is obtained with a high twist ratio (y/w = 5). However, the highest thermal performance (Nuc/Nus = 4.78) is obtained with the lowest twist ratio (y/w = 1.25).
KEYWORDS
PAPER SUBMITTED: 2017-06-14
PAPER REVISED: 2017-10-08
PAPER ACCEPTED: 2017-10-09
PUBLISHED ONLINE: 2018-02-18
DOI REFERENCE: https://doi.org/10.2298/TSCI170614042H
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2018, VOLUME 22, ISSUE Supplement 2, PAGES [S577 - S584]
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© 2018 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence