Scanning for hydraulic modelling

Hydraulic modeling can support the design of water features where there is a need to understand the shape and location of a water surface alongside the velocity and related flow phenomena. Examples include river management features such as weirs and spillways; and the design of optimal flow characteristics in white water courses (such as the recently redeveloped Teesside and the Olympic Lee Valley courses). Recent developments in Computational Fluid Dynamics (CFD ) mean that CFD simulations that would have been unfeasible even 5 years ago are now a realistic prospect for these challenging projects. However, there is still a vital need to validate models with experimental data, for non-standard designs this is rarely available. Terrestrial Laser Scanning (TLS) enables the CFD community to obtain high quality experimental data where other available options are typically prohibitively expensive or have an impact on the flow being measured. TLS is not traditionally used to measure the surface of water. Usually there is no return from the water; this in itself has many advantages when measuring the water-object interface for certain projects, but the broken water surface of white water offers some interesting results. The authors have investigated the effects of using TLS to measure standing waves and turbulent water such as that found on white-water rivers, the results have been applied to improve CFD simulations.