Copyright © 2018 Fadhil Abdul-Razzaq Kareem et. al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. International Journal of Engineering & Technology, 7 (4) (2018) 2575-2580 International Journal of Engineering & Technology Website: www.sciencepubco.com/index.php/IJET doi: 10.14419/ijet.v7i4.16698 Research paper Investigation The Exergy Performance of a Forced Draft Wet Cooling Tower Fadhil Abdulrazzaq Kareem 1 *, Mustafa J. Al-Dulaimi 2 , Noor Samir Lafta 1 1 Institute of Technology Baghdad, Middle Technical University, Baghdad, Iraq 2 Department of air conditioning and Refrigeration Engineering Technologies, Al Esraa university collage, Baghdad, Iraq *Corresponding author E-mail: Mustafa@esraa.edu.iq Abstract The performance of a forced draft wet cooling tower was investigated experimentally and the calculation was performed by applying second law of thermodynamics (exergy analysis). The mathematical model was developed by using engineering equation solver (EES) software. The results show that the chemical exergy of air increases from the bottom to the top of the cooling tower, the thermal exergy of air decreases from bottom to the top of the cooling, the exergy of water decreases from top to the bottom of the cooling tower. The exergy destruction decreases from bottom to the top of the cooling tower, and the exergy efficiency decreases from top to the bottom of the cooling. The exergy destruction tends to increase as the inlet wet bulb temperature increases while the exergy efficiency decreases. As water-air flow rate ratio increases the exergy destruction increases while the exergy efficiency decreases. The results show that there is an inverse proportional be-tween exergy destruction and exergy efficiency. Keywords: Exergy Efficiency; Cooling Tower; Exergy Destruction of Cooling Tower; Thermal Exergy; Chemical Exergy. 1. Introduction Cooling towers are commonly used in large thermal systems, such as industrial power generation units, refrigeration and air condi- tioning plants, chemical and petrochemical industries to dissipate process heat. The heat absorbed from such systems is dissipated to the atmosphere using the cooling tower. The heat is dissipated by convection between drops of water and external air and also by evaporation of small water droplets so that heat and mass transfer occurs in cooling tower [1]. Exergy analysis is a valuable thermo- dynamic strategy for evaluating and improving the efficiency of the systems so the exergy efficiency and exergy destruction, it can be used to optimize the economic performance of the systems [2]. T. Muangnoi [3] used the exergy analysis to indicate exergy and exergy destruction through the cooling tower. The model of the analysis was compared with experimental data. The results show that water exergy increases continuously from bottom to top of the cooling tower. Also it is noted that the exergy of the air increases continuously from bottom to top of the cooling tower. The results show that the highest exergy destruction is located at the bottom of the cooling tower, and finally the amount of exergy absorbed by air is smaller than that supplied by water. A. Ataei [4] introduced a mathematical model to predict the performance of a counter flow wet cooling tower using exergy analysis. The amount of exergy supplied by water is larger than that absorbed by air. The exergy corresponded to convective transfer decreases from bottom to the top of the cooling tower while the amount of that corresponding to evaporative heat transfer increases from the bottom to the top. The results showed that the exergy of air via convection has been was an increase from the bottom to the top of the cooling tower where the exergy of air via evaporation was decreasing from the bottom to the top of the cooling tower. On the other hand, the water exer- gy decreases from the top to the bottom of the tower. N. Bozorgan [5] presented a mathematical model to analyze the exergy of a counter flow wet cooling tower . The obtained results showed that the water makes more exergy than air. The results also showed that the water exergy decreases from the top to the bottom of the cooling tower, while the exergy of air increases from the bottom to the top of cooling tower. Khan et al [6] investigated the heat and mass transfer mechanism and performance characteristics of counter flow cooling towers using a detailed theoretical model. In this model, an approximate equation was used to calculate wet air enthalpy. This equation was obtained from the thermodynamic properties of saturated air-water vapor mixture. To obtain proper results calculating accurately the properties of wet air appears to be essential. Khalifa [7] proposed a mathematical model based on Merkel theo- ry with some simplifications to analyses the exergy of a counter flow Induced draught cooling tower. The result showed that exer- gy of water decreases from the top to the bottom of the cooling tower, the thermal exergy of air decreases from the bottom to the top of the cooling tower while the chemical exergy of the air in- creases from the bottom to the top of the cooling tower. Also, the results showed that the exergy destruction increases from the bot- tom to the top of the cooling tower. Q. S. Mahdi 2016 [8] in this study the performance analysis on the cooling tower depended upon the second law of thermodynam- ics, a prototype of the cooling tower was manufactured with ca- pacity of 9 kW, the result shows that the exergy destruction was depended on the inlet wet bulb temperature as the wet bulb tem- perature increase due to increase in the exergy destruction and this effect on the exergy efficiency, as the wet bulb temperature in- crease due to decrease in the exergy efficiency, and it is shown that the exergy destruction was directly proportional to water flow rate, air flow rate, and inlet cooling water temperature whereas. This research applies exergy analysis to investigate the perfor- mance of a forced draft wet cooling tower in Iraqi climate. The