Enhancement of the Brayton cycle efficiency by water or steam utilization

In the paper, thermodynamic analysis of two modifications of the Brayton cycle into enhancement cycles with water or steam injection are discussed. The first one deals with a water injected gas turbine modified system with both interstage compressed air cooling and air heating (heat regeneration) before combustion chamber. The second one, mainly devoted to higher steam to air ratio, is connected with separate steam production in the heat recovery steam generator. Hence, steam utilization for the gas turbine propulsion in the Cheng cycle has been analysed. The analysis has been based on the computational flow mechanics (CFM) models of these advanced humidified systems, thanks to which, the influence of the main thermodynamic and design parameters have been examined.