Design and Numerical Investigation of the Aft-Loaded Guide Vane of a Variable Nozzle Turbine

For the strong clearance leakage flow and shock wave in the guide vane of a variable nozzle turbine, an Aft-Loaded guide vane was redesigned and studied in stage environment. A comparison between the numerical and experimental results of the original vane was carried out to validate the numerical model under the design opening condition of the guide vane. Steady and unsteady numerical simulations were implemented for the original and designed vanes. The results indicate that the Aft-Loaded vane can decrease the total pressure loss by reducing the intensity of the leakage vortex. Meanwhile, the intensity of the throat shock wave and the trailing edge shock wave could also be weakened. The intensity weakening of the trailing edge shock wave and leakage vortex could reduce the static pressure fluctuation intensity of the rotor blades, and the reliability of the rotor blades will be enhanced.