Development of an Improved Desiccant-Based Evaporative Cooling System for Gas Turbines

The evaporative inlet cooling systems do not work well in humid areas. However, desiccant wheels can be used to dehumidify the air before passing it through the evaporative cooler. A previous study of combined direct and indirect evaporative coolers showed that a single desiccant wheel does not offer much higher effectiveness compared with the multistage evaporative systems. In this paper, additional dehumidification and indirect evaporative cooling stages are added to increase the effectiveness of the desiccant-based inlet cooling. A typical gas turbine cycle along with an industrial gas turbine with actual performance curves are used to study the performance of the proposed system in three different climatic conditions. It is shown that the added stages substantially improve the effectiveness of the desiccant-based inlet cooling.