Three-Dimensional Unsteady Turbulent Simulation and Analysis of Pressure Fluctuation in the Prototype Kaplan Turbine

In recent years, stability research of the hydraulic turbine has been one of the most important problems of analysis of the large turbines. In this paper, the simulation model is based on the large prototype Kaplan turbine of the Shuikou hydroelectric station in Fujian Province, China. The three-dimensional unsteady turbulent flow is simulated through the whole flow passage of the turbine mainly by FLUENT, and pressure fluctuation of several points in the passage are measured including the front of the stay vane, runner and the front of the draft tube, meanwhile, the frequency and amplitude of the pressure fluctuation are gained by FFT transform, through that we can find the source of the pressure fluctuation, therefore we will discuss the occurrence reason and spread elements of the pressure fluctuation in the flow passage of the turbine.