Simulating current-energy converters: SNL-EFDC model development, verification, and parameter estimation

Abstract

Increasing interest in power production from ocean, tidal, and river currents has led to significant efforts to maximize energy conversion through optimal design and siting and to minimize effects on the environment. Turbine-based, current-energy-converter (CEC) technologies remove energy from current-driven systems and in the process generate distinct wakes, which can interact with other CEC devices and can alter flow regimes, sediment dynamics, and water quality. This work introduces Sandia National Laboratories-Environmental Fluid Dynamics Code CEC module and verifies it against a two-dimensional analytical solution for power generation and hydrodynamic response of flow through a CEC tidal fence. With a two-dimensional model that accurately reflects an analytical solution, the effort was extended to three-dimensional models of three different laboratory-flume experiments that measured the impacts of CEC devices on flow. Both flow and turbulence model parameters were then calibrated against wake characteristics and turbulence measurements. This is the first time that turbulence parameter values have been specified for CEC devices. Measurements and simulations compare favorably and demonstrate the utility and accuracy of this numerical approach for simulating the impacts of CEC devices on the flow field. The model can be extended to future siting and analyses of CEC arrays in complex domains. © 2017 Elsevier Ltd.