Comparative Evaluation of Advanced Gas Turbine Cycles With Modified Blade Cooling Models

摘要

Advanced gas turbine cycles use advanced blade cooling technologies to reach high turbine inlet temperature. Accurate modeling and optimization of these cycles depend on blade cooling model. In this study, different models have been used to simulate gas turbine performance. The first model is the continuous model and the second is stage-by-stage model with alternative methods for calculating coolant, stagnation pressure loss and SPR. Variation of specific heat and enthalpy with temperature are included in both models. The composition of gas stream in turbine is changed step by step due to air cooling. These models are validated by two case study gas turbine results, which show good agreement with manufacture's data. Then using these models, a comparison between continuous and stage by stage models is done. Results show that the stage by stage model can be improved to use in variable CPR by changing number of turbine stages. Also, the number of film cooled rows and coated rows change the number of cooled rows. This also increases power, efficiency and TET, while reduces coolant mass flow. For high TIT and with current blade cooling technology, efficiency seems to have no increase relative to lower TIT. CAP increases power but decreases efficiency, where with FP efficiency also increases, while power increases too.