Turbulent Flow Measurement in Vortex Settling Basin

Abstract

This paper presents the findings of an experimental study on the three-dimensional turbulent flow field in vortex settling basin. An ADV (Acoustic Doppler Velocity Meter) were used to catch 3D velocity components inside the basin. Detailed measurements of time-averaged velocity components, turbulent intensity components and turbulent kinetic energy were determined at different radial sections of chamber. Also the normalized time averaged absolute velocity of 3D components in contour type exhibition were conducted and it was found that the absolute velocity generally is influenced by u component of flow. It trends from high magnitude in basin center to the constant magnitude in basin side wall. The normalized turbulent intensity of three components was investigated individually. It was found that intensity of 3D components in vicinity of central air core is higher than other regions, decreasing by moving towards basin sidewall except for the sections that influenced directly by entrance flow jet and sidewall exiting overflow. The results of turbulence kinetic energy also had the same interpretation like turbulence intensity and affected by the same boundary conditions which cover turbulence intensity of 3 velocity components overly.