Transient Analysis of Inlet Fogging Process for Gas Turbine Systems

Gas turbine inlet fogging is a method of cooling intake air by injecting demineralized water in the duct through the special atomizing nozzles. Gas turbine cycles with inlet fogging could offer enhanced efficiency with low complexity, so the inlet air-cooling is considered the most cost-effective way to increase the power output as well as thermal efficiency of gas turbines. In this work the inlet fogging process is modeled based on the evaporation of droplets. Transient behaviors of the process are investigated with analytic expressions obtained by considering heat and mass transfer and thermodynamic relations. Effects of water injection ratio on the transient behaviors of temperature of mixed air, mass of liquid droplets, mass flux and heat transfer from the droplets are thoroughly investigated. Results show also the dependencies of system parameters on the critical injection ratio and evaporation time.