Characteristic prediction method of transonic axial flow turbine

Abstract

ObjectivesRegarding transonic flow occurring at the throat of the stator blades of axial flow turbines at high subsonic and transonic speeds, it is will need a long period of time to have 3D reseach and to obtain the characteristic parameters. Therefore, an cost-effective approach for predicting turbine characteristic is required.MethodsThe existing loss models are integrated to predict turbine characteristics via one-dimensional programming and verify them via three-dimensional numerical simulation.ResultsThe results show that the relative error of the isentropic stage-temperature ratio is 11.53%, that of the stage-expansion ratio is 11.77% and that of the reaction degree is 14.23%. Whether transonic phenomena occur at the static blade is judged accurately. The adiabatic index of the outlet temperature of the rotor blade is used to estimate the characteristics of the single-stage turbine accurately. ConclusionsWithin the range of acceptable error, this method allows the fast and accurate prediction of transonic turbine characteristics, thus reducing calculation time.

Keywords

• transonic turbine
• characteristic estimation
• axial flow turbine
• adiabatic index