Library Subscription: Guest
Home Archives Officers Future meetings Assembly for International Heat Transfer Conferences
International Heat Transfer Conference 8

ISSN: 2377-424X (online)
ISSN: 2377-4371 (flashdrive)

INFLUENCE OF TUBE SPACING AND FLOW RATE ON HEAT TRANSFER FROM A HORIZONTAL TUBE TO A FALLING LIQUID FILM

Jovan Mitrovic
Retired from University Paderborn., Institut fur Technische Thermodynamik und Thermische Verfahrenstechnik, Universitat Stuttgart, Pfaffenwaldring 9 7000 Stuttgart 80, F.R. Germany

Abstract

Many engineering operations involve heat transfer between a bundle of horizontal tubes and a falling liquid film. Numerous investigations, which show the influence of the liquid flow rate on heat transfer have been carried out. However, at present, studies, in which the effect of the tube spacing on heat transfer was systematically investigated in a larger range of influence parameters, are unavailable.
In the present paper, the results of an experimental study of heat transfer from a horizontal heated tube to a falling, subcooled liquid film are discussed. The diameter of the tube used in the experiments was 18 mm. Two liquids, isopropylalcohol and distilled water, were used as test fluids. The flow rate of the liquid, i.e. the Reynolds number, and the spacing between the spray and the test tube were varied as parameters.
It is shown that the heat transfer from the heated surface to the liquid film depends not only on the Reynolds number but also on the tube spacing and on the flow pattern. The heat transfer coefficient increases with an increase in tube spacing over the entire range of the Reynolds numbers investigated. This increase is more pronounced at higher values of the Reynolds number. With a decrease in the Reynolds number, the influence of tube spacing on heat transfer becomes smaller and can be neglected, for practical purposes, for Reynolds numbers below approximately 80.

Download article Publication Ethics and Malpractice Recommend to my Librarian Bookmark this Page