Experimental analysis for the determination of the convective heat transfer coefficient by measuring pressure drop directly during annular condensation flow of R134a in a vertical smooth tube
Journal article
Authors/Editors
Strategic Research Themes
No matching items found.
Publication Details
Author list: Dalkilic A.S., Teke I., Wongwises S.
Publisher: Elsevier
Publication year: 2011
Journal: International Journal of Heat and Mass Transfer (0017-9310)
Volume number: 54
Issue number: 4
Start page: 1008
End page: 1014
Number of pages: 7
ISSN: 0017-9310
eISSN: 1879-2189
Languages: English-Great Britain (EN-GB)
View in Web of Science | View on publisher site | View citing articles in Web of Science
Abstract
This study investigated the direct relationship between the measured condensation pressure drop and convective heat transfer coefficient of R134a flowing downward inside a vertical smooth copper tube having an inner diameter of 8.1 mm and a length of 500 mm during annular flow. R134a and water were used as working fluids on the tube side and annular side of a double tube heat exchanger, respectively. Condensation experiments were performed at mass fluxes of 260, 300, 340, 400, 456 and 515 kg m-2 s-1 in the high mass flux region of R134a. The condensing temperatures were around 40 and 50 ฐC; the heat fluxes were between 10.16 and 66.61 kW m-2. Paliwoda's analysis, which focused mainly on the determination of the two-phase flow factor and two-phase length of evaporators and condensers, was adapted to the in-tube condensation phenomena in the test section to determine the condensation heat transfer coefficient, heat flux, two-phase length and pressure drop experimentally by means of a large number of data points obtained under various experimental conditions. ฉ 2010 Published by Elsevier Ltd. All rights reserved.
Keywords
Two-phase pressure drop, Vertical downward flow
Contact Information