Article Sidebar
Published:
Jun 30, 2008Keywords:
Article Details
Tanzania Journal of Engineering and Technology (Tanz. J. Engrg. Technol.) publications are written as a basis for academic discussions. Whereas effort is made by the Editorial Board to screen out inaccurate or misleading statements, data or opinions, Tanz. J. Engrg. Technol. wishes to make it clear that the contents of the articles are the sole responsibility of the authors. Accordingly, the Editorial Board and editors, publisher, College of Engineering and Technology and the University of Dar es Salaam accept no responsibility or liability whatsoever for the opinions, inaccurate or misleading data or statement and views expressed by the authors.
However, the College of Engineering and Technology, the publisher of the Journal, reserve all rights of the articles published in the Journal. Whereas the contents of the articles are available electronically without cost, no part of the publication may be transmitted in any form or reproduced electronically or mechanically, except for short extract in critical scholarly review, research or discourse with an acknowledgement.
Main Article Content
Modeling of a Spray Assisted Natural Draft Cooling Tower
Abstract
Cooling towers are one of the largest heat and mass transfer devices that are in common use. A novel type of cooling tower has been proposed in which air flow rate into the tower is drawn by ejector action of sprays instead of fans as is done in conventional mechanical forced or induced draft cooling towers. This novel design offers the potential of saving
the energy cost for driving the fan. The paper presents mathematical models for momentum transfer which is the driving force causing the entrainment of air. Also the heat transfer model for co-current flow of liquid and gas in the tower has been presented. The liquid to gas ratio tend to decrease as liquid rate increases. The ratio attained in the experimental
laboratory tower was 3.3, correspondingly the Momentum transfer efficiency for the tower was 60% and was the highest. Experiments for cooling water initially at 45 o C to final water temperature 27 o C showed that the cooling tower efficiency was 54% and number of transfer unit 0.8.
