Computational Fluid Dynamics Analysis and Validation with Field Test of 1 MW Hydropower Turbine System

Abstract

This study analyzed and validated a 1 MW hydropower turbine system using computational fluid dynamics (CFD) in conjunction with field test data. The fluid domain of the hydropower system includes the runner blade, vane, duct, and both inflow and outflow free surface flows. An implicit unsteady flow solver and the SST k-omega turbulence model were employed. The rotational motion of the rotor blade was simulated using the moving reference frame (MRF) method. To handle a non-conformal mesh among the intake, runner, and outlet domains, an internal interface boundary condition was applied. System performance was evaluated by adjusting the guide vane opening ratio and the runner blade pitch angle. A free surface model was also developed to accurately represent the water level. The results show that the CFD analysis predicted the turbine's power output with a maximum deviation of 1.7% from field test measurements under different tide conditions. The numerical analysis also confirmed the influence of the runner blade pitch angle, with a 1 degrees change in pitch angle leading to a 68 kW variation in power output. The accuracy of the CFD analysis was verified by comparing it to performance data from actual field tests.