Numerical Investigation of Effect of Blade Profile on the Supersonic Gas-Turbine’s Performance under the Partial-Admission Conditions

The supersonic turbines are widely used in various industries and power generation systems, including gas turbines, space propulsion, heavy transport industries, and etc. In general, these turbines are used when a high specific work with a low fluid Mass flow is needed. It is possible to extract a high specific work from small height supersonic impulse blades in these turbines. To prevent losses due to the low blades aspect ratio, the turbine is used in partial-admission conditions; so that, the fluid flow is only fed from a part of the rotor. The degree of partial-admission and the type of blade profile are important factors that have significant effects on the turbine performance. The aim of this work is to design and investigate the effects of various types of impulse blade profiles on the turbine’s performance. A preliminary design code is developed in order to predict turbine performance. These results are evaluated using the experimental results. In the next step, using the calculation of design code, two-dimensional profiles are created using different design methods and numerically analyzed. Finally, the profiles that were better than the original model were studied by 3D numerical analysis. It was found that the performance parameters such as efficiency, power, and torque are increased by more than 8% in the selected best model, in comparison with the original model. Moreover, the total pressure loss is 12% decreased for the selected model. In general, the results show that the selected profile would have a superior performance.