Author(s): Michael Marek; Thorsten Stoesser; Philip J. W. Roberts; Volker Weitbrecht; Gerhard H. Jirka
Keywords: CFD; URANS; Jets; Turbulent mixing processes; Water storage tanks
Abstract: Mixing processes in water storage tanks are an important factor for maintaining an adequate quality of drinking water. The flow and mixing in these tanks are often investigated with extensive experimental studies. However, much progress has been made in recent years in numerical simulation techniques, and with the growth in speed and capacity of modern supercomputers, computational fluid dynamics (CFD) simulations can now be a valuable addition to the laboratory experiments. In this paper we present the results of three-dimensional URANS simulations of the flow and entrainment processes in a jet-mixed tank. Several variations of jet velocity, nozzle diameter and nozzle angle are investigated, and two differencing schemes with different accuracies to approximate the convective fluxes are applied. The predicted results are compared to experimental data as well as to other CFD results taken from the literature. The main objective of the work presented is to develop a CFD code that can be used as a flexible modelling tool for the design and optimization of water storage tanks including the effects of varying water depths and density stratification.