Objectives  In order to improve the working performance of gas turbines, this study examines the aerodynamic performance of variable geometry turbine clamshell guide vanes.

  Methods  Taking a typical variable geometry turbine guide vane as a prototype, a clamshell turbine guide vane model with a fixed pressure side and rotating suction side is constructed. Numerical simulation based on the shear-stress transport (SST) model is then carried out to analyze the parameter variation laws of the clamshell turbine guide vane and ordinary variable geometry turbine guide vane under different working conditions.

  Results  As the calculation results show, when the rotation angle of the guide vane varies from +3° to –3°, the aerodynamic performance of the clamshell turbine guide vane has certain advantages, a larger flow rate and a smaller total pressure loss coefficient. When the guide vane rotation angle exceeds +3°, its flow rate increase will decrease significantly and even stop or negatively increase. When the rotation angle of the suction surface gradually increases from a negative angle to 0°, the total pressure loss coefficient will gradually decrease. When the rotation angle is greater than 0°, the total pressure loss coefficient will increase with the rotation angle.

  Conclusions  The adoption of clamshell turbine guide vanes can improve the aerodynamic performance of turbines to a certain extent.