Effect of Changing Maximum Camber Position of the Turbine Blade on its Aerodynamic Performance

This study presents numerical investigation for studying the effect of changing maximum camber position of turbine blade and different operating conditions on its aerodynamic performance and the flow pattern through turbine blade passage. Three different turbulence models, namely Standard k-ε, RNG k-ε, and Realizable k-ε are used to select the suitable turbulence model. Four turbine blades with different values of maximum camber position (t_m/C), namely 0.157, 0.23, 0.26 and 0.37 measured from blade leading edge are studied. The tested blade geometries are created and meshed by using ICEM, ANSYS software. The governing equations including mass, momentum, and energy equations are numerically solved using ANSYS Fluent 2017. Comparison of numerical results using the three different turbulence models with several published experimental data showed that the realizable k- ε turbulence model is suitable for simulating the flow characteristics through the turbine blade passage. The numerical results indicated that, changing the maximum camber position of the turbine blade significantly affects the pressure coefficient on the suction surface of the blade while its effect is small on the pressure surface of the turbine blade at different operating conditions. Finally, it can be concluded that, the best aerodynamic performance of the tested turbine blades, at constant values of, pitch-to-chord ratio of 0.9 and incidence angle of 0o, is achieved if the position of maximum camber of the turbine blades is located at approximately (x/c), 0.157 from the leading edge.