The process is adiabatic in evaporative cooling; enthalpy and wet-bulb temperature of the air remains stable during the cooling. The dry bulb temperature and relative humidity of the air which will be exposed to cooling reveals the activity of cooling to be carried out.

In evaporative cooling technique, the water is expected to evaporate at maximum rate and it is aimed to match the inlet air temperature with wet-bulb temperature. The systems developed in accordance with this goal are generally media type evaporative cooling systems and fogging systems.

In media type evaporative cooling units, the contact of water and air in appropriate time and at maximum rate is the basic principle. Therefore, the evaporative cooling pads with their special surface geometry and material enables water to evaporate rapidly over a wide area.

Water supply is provided for cooling pads installed in front of the gas turbine inlet air through special mechanism. A significant amount of water circulating over pad surface contacts to air circulating inside the pad; therefore it evaporates and penetrates into air.

At the end of this process, inlet air cools down and its relative humidity increases and it leaves the pad. Evaporation degree is obtained through the control and observation of feeding and blow off water flow, circulation water conductivity, inlet air saturity rate, temperature-humidity etc.

Media type evaporative cooling system provides full security cooling for gas turbines with their zero droplet risk property. That’s one of the important reasons why turbine manufacturers and users prefer evaporative cooling systems instead of fogging and other pulverization systems.