TY - JOUR
TI - Coupling model and solving approach for performance evaluation of natural draft counter-flow wet cooling towers
AU - Wang Wei
AU - Zeng Deliang
AU - Hu Yong
AU - Liu Jizhen
AU - Niu Yuguang
JN - Thermal Science
PY - 2016
VL - 20
IS - 1
SP - 291
EP - 301
PT - Article
AB - 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.