Experimental Validation of Numerical Model of Flow in Pump-Intake Bays

Experiments were conducted in a laboratory model to validate a numerical model developed to simulate the three-dimensional turbulent flow in a water-pump-intake bay. The laboratory model was designed to reproduce the essential flow features of practical installations, including free-surface and wall-attached vortices, but was geometrically simple to enable the numerical model to be applied without undue complications of grid topology. The experiments involved flow visualizations and measurements with particle image velocimetry. The numerical model solves the Reynolds-averaged Navier-Stokes equations with a near-wall turbulence model. In the validation of this numerical model, therefore, emphasis was placed on prediction of the average properties of the various types of vortices that were found in the experiments. The predicted number, location, and general structure of the vortices were found to be in good agreement with those observed in the experiments, but they were generally larger and weaker than the measured ones. These differences are attributed to the unsteadiness of the flow and inadequacy of the turbulence model.