Design of the Auxiliary Flow Components of the Centrifugal Turbine

Centrifugal turbine flow components mainly includes: inlet, stator and rotor cascade, vaneless diffuser, outlet. In this paper, the meridian plane design of the throughflow sections without the stator and rotor cascade had been analyzed. The design of inlet meridian plane obey the uniform section method, which can ensure air enters uniformly and axial symmetry; the vaneless diffuser meridian plane side was parallel, and the optimal outlet diameter according to the principle of the optimal overall efficiency; the outlet meridian plane adopt the contour of the circular bending pipe. With a centrifugal turbine as an example, which throughflow sections are designed by using this method, the stage efficiency is 88.505% and machine efficiency was up to 90.34% and wheel power was 478.9 kW obtained by numerical simulation, the performance in line with expectations. The results show that using this method to design auxiliary flow components is simple, specially suitable for the engineering application.