ISSN Online: 2377-424X
ISBN Print: 978-1-56700-421-2
International Heat Transfer Conference 15
Experimental Research on Falling Film Flow Characteristic for Horizontal Drop-shaped Tube Bundle in Cold State
Abstract
In order to better understand the mechanism of liquid falling film flow on the horizontal cylinder tube bundle, a
new kind of drop-shaped tube is presented in this paper. Visualization experimental study was conducted to
investigate the falling film flow characteristic of the drop-shaped tube in cold state. The effects of the tube type,
Reynolds number and intertube spacing on the falling film modes, dimensionless wavelength and film thickness
for the drop-shaped tube were studied. Compared with the circular tube, the more stable flow modes of the dropshaped
tube can be obtain at a lower Reynolds number. The influence of intertube spacing is large on falling film
modes, and smaller intertube spacing is help to form of the sheet mode. Under the conditions of this study, the
falling wavelength increases with the decrease of Reynolds number and firstly increases then tends towards
stability with increasing of intertube spacing. The study found that the falling wavelength of the drop-shaped
tube is smaller than that of the circular tube by 12.97 percent at an intertube spacing of 5 mm. The film thickness
of the drop-shaped tube grows with the increase of the Reynolds number and the growth rate decreases. The
minimum film thickness of the drop-shaped tube is smaller than that of the circular tube. Finally the conclusions
of this paper have a certain reference significance and value to the application of the shaped tube in the falling
film evaporator for the seawater desalination system.