Effect of Number of Blades on Performance of an Axial Gas Turbine

In the present work, the effects of blades number on the performance of two stages axial gas turbine have been investigated numerically. Geometry characteristics of the gas turbine have been chosen based on the F5 model of General Electric Company. First, the blades geometry and fluid passages are initially generated due to the real dimensions of the turbine and the generated geometry is networked. Then, the final model of the turbine is generated by gridding blades which set beside each other. Then, Ansys CFX software is used to solve the 3D Navier-Stokes equations in the generated computational domain. The shear stress transport turbulence model has been employed in order to determine the wall effects on the turbulent flow. Before any change in the main turbine, a numerical study was performed and a comparison was conducted between the numerical results and experimental results measured in the power station which the results show a good level of agreement between them. The number of blades of each row has been changed in order to investigate the effects of blade number on the turbine efficiency. The results show that the power generation of the turbine and its efficiency are increased by 0.83% and 0.81%, respectively by an increase in the number of second-row stator blades from 62 to 71 blades.