The Use of CFD Coupled with Physical Testing to Develop a New Range of Vortex Flow Controls with Attributes Approaching the Ideal Flow Control Device

Abstract

Vortex flow controls (VFC) are devices which are well suited for use in drainage systems, as they exhibit non-constant, non-linear discharge coefficients that can be tailored to approach that of a constant flow-rate device. Also, they have no mechanical components or power requirements and have a reduced risk of blockage compared with traditional flow controls. However, due to their complex bi-stable discharge behaviour and the influences of turbulence, the design and scaling of these devices, is not a trivial process. In this paper a VFC design methodology is presented that enables the VFC geometry to be determined and optimized to approach the ideal hydraulic behaviour, for a given discharge limit. This is achieved through the calibration of simplified, axi-symmetric vortex solutions of the Navier-Stokes relationships, by means of Computational Fluid Dynamic (CFD) analysis and experimental hydraulic assessment.