Tuan Ta, Thames Water
In the Water industry, almost all is free surface flow. A slow varying water surface is found when filling and emptying a water storage tank; still slow turbulent flow is found in the flow distribution channels, and higher turbulent flow is found in the pump sumps. Understanding the free surface flow is important for the engineering design and for the process performance optimisation.
Current computational fluid dynamic (CFD) simulations experience difficulties with free surface flow problems. Assumptions have to be made to simplify the problem into single phase calculations. More models using Volume of Fluid method and Eulerian-Eulerian multiphase are becoming available but, in these models, there remains the uncertainty in locating the water surface.
ACUSIM’s free surface modelling capability is seen as an alternative. This paper presents the results of current investigations.