Thermodynamic evaluation of different gas turbine blade cooling techniques

The key to the successful and strong gas turbine technology bases significantly upon the introduction of new materials and/or the usage of efficient means & methods of turbine blades cooling. Present paper deals with the comparative evaluation of the cooling effectiveness for different methods of turbine blade cooling. Different cooling techniques such as internal cooing, film cooling and transpiration cooling have been considered for the study with compressed air as cooling medium. The performance results of the gas turbine have been expressed in terms of overall efficiency and specific power of the gas turbine cycle, which significantly depend on the type of blade cooling employed. The independent variables considered are the TIT, compressor pressure ratio and the inlet coolant temperature. Cooled gas turbine model, modeling of all components of gas turbine cycle and gas properties model have been used for parametric analysis. A computer code ldquoGTANALYSrdquo has been developed to perform all the calculations.