Modifications on the stator blade geometry of the first three stages in the intermediate-pressure-cylinder of a steam turbine were proceeded to improve the aerodynamic characteristics using negative-twist method and bowedtwist method.Numerical simulations of the three-dimensional flow in the multistage cascades were completed for both the original and the modified blade designs,which provide the basis to analyze the effects of the modifications on the flow characteristics.The multistage efficiencies of the ...