A metastable wet steam turbine stage model

Abstract A model for the prediction of the efficiency of axial flow steam turbine stage is described, where the flow through turbine cascade is considered non-homogeneous and metastable. At the exit an oblique shock brings it to equilibrium. The losses in the cascade are expressed according to Dunham and Came (Trans. ASME (1970)) and Kacker and Okapuu (J. Eng. Power (1982)) which is imprivemente of Ainley and Mathieson (1951) method. Two phase flow frictional multiplier is used as a correction factor for pressure coefficient. The model is compared with data of performance evaluation of large steam turbines of PWR power plants and results shows a good agreement