Power Generation Analysis for High-Temperature Gas Turbine in Thermodynamic Process

A thermodynamic process of power generation has been developed for a gas turbine, a steam turbine, and a compressor, supported by adiabatic expansion or compression processes. Recently, the possible inlet temperature of gas turbines has been increased to 1500°C or more, and the inlet temperature of steam turbines also has been increased to 650°C. At these high-temperature conditions, turbine nozzles or blades have to be cooled by some devices. When we use the adiabatic expansion or compression process, it is necessary to check the fluid-dynamic friction caused by fluid flow between the nozzle and blade. However, considering the high-temperature gas or steam turbine, the nozzle and blade have a cooling effect and frictional heat generation. Furthermore, if we introduce a new concept of internal cooling devices for the compressor to reduce its driving power, the compression process has the cooling effect as well as frictional heat generation. In addition, another new concept for a continous reheating system for gas turbine may improve the thermal efficiency of the combined cycle. These thermodynamic processes of expansion and compression with heat sources and cooling devices to estimate the power generation of turbine and the driving power of a compressor are analyzed. Then, the analytical results are set up and differentiated by their adiabatic, cooled, and heated processes.