THERMAL SCIENCE

International Scientific Journal

Wei Wang

,

Deliang Zeng

,

Yong Hu

,

Jizhen Liu

,

Yuguang Niu

COUPLING MODEL AND SOLVING APPROACH FOR PERFORMANCE EVALUATION OF NATURAL DRAFT COUNTER-FLOW WET COOLING TOWERS

ABSTRACT
When searching for the optimum condenser cooling water flow in a thermal power plant with natural draft cooling towers, it is essential to evaluate the outlet water temperature of cooling towers when the cooling water flow and inlet water temperature change. However, the air outlet temperature and tower draft or inlet air velocity are strongly coupled for natural draft cooling towers. Traditional methods, such as trial and error method, graphic method and iterative methods are not simple and efficient enough to be used for plant practice. In this paper, we combine Merkel equation with draft equation, and develop the coupled description for performance evaluation of natural draft cooling towers. This model contains two inputs: the cooling water flow, the inlet cooling water temperature and two outputs: the outlet water temperature, the inlet air velocity, equivalent to tower draft. In this model, we furthermore put forward a soft-sensing algorithm to calculate the total drag coefficient instead of empirical correlations. Finally, we design an iterative approach to solve this coupling model, and illustrate three cases to prove that the coupling model and solving approach proposed in our paper are effective for cooling tower performance evaluation.
KEYWORDS
counter-flow wet cooling tower, coupling model, merkel equation, outlet water temperature, inlet air velocity, performance evaluation
PAPER SUBMITTED: 2014-09-24
PAPER REVISED: 2015-01-12
PAPER ACCEPTED: 2015-01-16
PUBLISHED ONLINE: 2015-01-24
DOI REFERENCE: https://doi.org/10.2298/TSCI140924006W
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2016, VOLUME 20, ISSUE Issue 1, PAGES [291 - 301]
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Coupling model and solving approach for performance evaluation of natural draft counter-flow wet cooling towers

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence