Investigation of Evaporative Mass Transfer with Turbulent-Forced Convection Air Flow over Roughness Elements
Publication: Journal of Hydrologic Engineering
Volume 19, Issue 11
Abstract
The effect of obstruction in the form of creation of additional turbulence caused by roughness elements on evaporation rates and hence on the convective mass transfer coefficient has been investigated under varying conditions of air velocities and water temperatures. The respective ranges of flow Reynolds number and water temperature for this study were 20,000–120,000 and 30–50°C, respectively. The range of relative roughness height was 0.011–0.075. It has been found that there is a significant effect of the presence of roughness elements, and this effect is a strong function of flow Reynolds number and the relative roughness height of its obstructions. An empirical correlation has been developed to relate Sherwood number as a function of Reynolds number and relative roughness height to facilitate prediction of mass transfer and evaporation rate under varying Reynolds number and relative roughness height.
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Published In
Journal of Hydrologic Engineering
Volume 19 • Issue 11 • November 2014
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Oct 9, 2012
Accepted: May 19, 2014
Published online: Jul 9, 2014
Published in print: Nov 1, 2014
Discussion open until: Dec 9, 2014
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