**5. References**


**3** 

*Yanbu Industrial City,* 

*Saudi Arabia* 

*King Abdulaziz University, Jeddah* 

**Energy, Exergy and Thermoeconomics** 

**Analysis of Water Chiller Cooler** 

**for Gas Turbines Intake Air Cooling** 

Rahim K. Jassim1, Majed M. Alhazmy2 and Galal M. Zaki2

*2Department of Thermal Engineering and Desalination Technology,* 

*1Department of Mechanical Engineering Technology, Yanbu Industrial College,* 

During hot summer months, the demand for electricity increases and utilities may experience difficulty meeting the peak loads, unless they have sufficient reserves. In all Gulf States, where the weather is fairly hot year around, air conditioning (A/C) is a driving factor for electricity demand and operation schedules. The utilities employ gas turbine (GT) power plants to meet the A/C peak load. Unfortunately, the power output and thermal efficiency of GT plants decrease in the summer because of the increase in the compressor power. The lighter hot air at the GT intake decreases the mass flow rate and in turn the net output power. For an ideal GT open cycle, the decrease in the net output power is ~ 0.4 % for every 1 K increase in the ambient air temperature. To overcome this problem, air intake cooling methods, such as evaporative (direct method) and/or refrigeration (indirect

In the direct method of evaporative cooling, the air intake cools off by contacts with a cooling fluid, such as atomized water sprays, fog or a combination of both, [Wang 2009]. Evaporative cooling has been extensively studied and successfully implemented for cooling the air intake in GT power plants in dry hot regions [Ameri *et al.* 2004, 2007, Johnson 2005, Alhazmy 2004, 2006]. This cooling method is not only simple and inexpensive, but the water spray also reduces the NOx content in the exhaust gases. Recently, Sanaye and Tahani (2010) investigated the effect of using a fog cooling system, with 1 and 2% over-spray, on the performance of a combined GT; they reported an improvement in the overall cycle heat rate for several GT models. Although evaporative cooling systems have low capital and operation cost, reliable and require moderate maintenance, they have low operation efficiency, consume large quantities of water and the impact of the non evaporated water droplets in the air stream could damage the compressor blades [Tillman *et al* 2005]. The water droplets carryover and the resulting damage to the compressor blades, limit the use of evaporative cooling to areas of dry atmosphere. In these areas, the air could not be cooled below the wet bulb temperature (WBT). Chaker *et al* (2002, 2003), Homji-meher *et al* (2002)

method) has been widely considered [Cortes and Williams 2003].

**1. Introduction** 

