Computational Hydraulics

Computational hydraulics is an applied science aiming at the simulation by computers of various physical processes involved in seas, estuaries, rivers, channels, lakes, etc. It is one of the many fields of science in which the application of computers gives rise to a new way of working, which is intermediate between purely theoretical and experimental. This discipline is not an independent development, but rather a synthesis of various disciplines like applied mathematics, fluid mechanics, numerical analysis and computational science.

One of the main objectives of computational hydraulics is to obtain simulations of processes of flow and transport in open water bodies as detailed and as accurately as required within a predefined framework of specifications. Knowledge of aspects that control this accuracyis therefore of crucial importance. Although simulations provide a route for solving and analysing complex physical systems, they require considerable care to ensure that the numerical solution is a valid solution of these systems. Hence, verification and validation of numerical models have become indispensable part of the job.

In hydraulic engineering there is a growing need to integrate different physical processes residing in multiple time and space scales like waves, tides, river discharge and sediment transport. This need is prompted by a continuous strive for more insight, reliability and efficiency. Rapid advances in computer hardware in recent years have made it possible to develop such a fully-integrated, multi-scale numerical model. Examples are the ADCIRC+SWAN modelling framework and our flexible mesh, non-hydrostatic, free-surface flow models FINLAB and H2Ocean.

Within the section Environmental Fluid Mechanics we focus on research and education related to the development of spectral wave model SWAN (Simulating Waves Nearshore) and non-hydrostatic wave-flow model SWASH (Simulating Waves till Shore). These state of the art models are important tools and can be used to predict the generation, propagation and dissipation of wind waves and swells in coastal regions and harbors. Accurate prediction of these processes is essential to study and analyse nearshore hydrodynamics and solute transport in the coastal area. There is a strong link with the chair Free-surface waves.

Efficiency and accuracy are the key aspects in our research. The scientific challenge is to develop numerical methods or algorithms that enable to compute a more accurate solution in a more efficient manner. Efficient algorithms can strongly reduce computing time and make existing computer models more suitable for real-life applications. Also the development of these algorithms should lead to a seamless implementation on peta- and exascale architectures. Examples are developments of tailor-made numerical algorithms related to parallel computing (GPU, MPI) and flexible meshes (FVM, FEM).

Load-balanced partitioned unstructured grid for the SWAN model of the Wadden Sea.