Presentations

Abstract

Often overlooked, Coriolis force contributes to wake-deficit recovery, and is absent from typically used engineering models of wind farm wakes. New theoretical work has shed light on the importance of including Coriolis forcing when predicting wakes from offshore wind farms. While the Coriolis force acts to partly restore the slowed air in the wake, it also accelerates the flow outside the wake causing an "edge jet". A simple expression has been derived which relates the relative importance of Coriolis compared to turbulent mixing in recovering wakes. Also, the effect of cluster size and atmospheric inversion strength can be combined into a non-dimensional farm scale parameter which also enables insights into the relative importance of Coriolis in wake recovery. These theoretical results will be presented (details will be provided separately in a journal paper [1]), and compared with an extended version of an atmospheric boundary layer / wind farm model [2]).   The implications of this work are that Coriolis forcing appears to provide significant mitigation of far-wake effects from very large offshore wind farm clusters, becoming increasingly important with increasing cluster scale. Worked examples will be provided and wider implications discussed.    [1] Journal paper in preparation “Coriolis Recovery of Wind Farm Wakes”, R B Smith and B J Gribben, 2025.   [2] Smith, R. B.: Gravity Wave Effects on Wind Farm Efficiency, Wind Energy, 13, 449–458, https://doi.org/10.1002/we.366, 2010.