Power boost of gas turbines by inlet air cooling

The design of a power boost system for an existing gas turbine unit using a direct spray evaporative spray cooling method is described in this paper. Experiments were conducted to determine the extent of cooling possible by this method, droplet size requirements and spray water requirements. Although up to 4.9% of power boost is theoretically possible at the design conditions of 32.2°C (90°F) and 60% relative humidity, various other constraints limit the actual power boost to about 3.8% of the nominal power. For small values of the wet-bulb depression (less than about 5°C or 10°F), the required droplet sizes for complete evaporation become so small (of the order of 5-10 microns with high flow rates) that production of them at the required flow rates is a challenging task