Sandia completed two performance-testing studies for hydrokinetic canal effects at Roza Canal in Yakima, Washington. Sandia National Laboratories’ Environmental Fluid Dynamics Code (SNL-EFDC) was used to model the canal and the current-energy-capture device. The first was an evaluation of different grid sizes and refinements to determine an appropriate grid for future modeling efforts. The second study was a set of parameter sweeps to evaluate the impact of important model parameters on the wake characteristics using the optimum grid determined from the first study.
For the grid-sensitivity study, three grids were generated, all of which use the same bathymetric data for the Roza Canal. Converged results were achieved with the 19,777-cell grid. Because high resolution is not needed throughout the entire model domain for the second study, the 19,777-cell grid was coarsened in portions of the canal away from the turbine location to improve computational efficiency without sacrificing accuracy.