Numerical Simulations of Marine Hydrokinetic Devices in Complex Bathymetries

Abstract

The Chacao channel in southern Chile has been identified as an important tidal energy resource that can potentially contribute a significant power capacity in the near future. The installation of marine hydrokinetic (MHK) turbines will require evaluating the impacts and the interaction of devices under real conditions, with the purpose of optimizing the energy extraction and assessing their local environmental effects. Motivated by the need to learn more about the physical and environmental processes related to the installation of turbine arrays in this site, we carry out a study that includes detailed field measurements of bathymetry, laboratory experiments, and numerical simulations of devices for a wide range of scales, with the objective of studying wake-bathymetry interactions and their environmental effects. In this investigation we present the simulations performed with a 3D numerical model using the actuator disk parameterization, and using a coherent-structure resolving turbulence model. The results are validated with experimental data, and show the interaction of the devices and potential local impacts at intermediate scales. By using bathymetry data in the Chacao channel, we simulate flows in arbitrarily complex geometry, discussing the interaction of the turbines with the features of the natural terrain. Keywords— Marine energy, Actuator disks, Hydrokinetic turbines, 3D Numerical simulation, DES Numerical simulation