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arXiv · 2605.30077

Two-way coupling of gravity waves and wind farm wakes: a reduced-order boundary-layer model

Hossein A. Kafiabad·Majid Bastankhah
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Abstract

This paper develops a reduced-order numerical framework for modelling the two-way coupling between gravity waves and turbulent wakes in large-scale wind farms. Starting with the non-hydrostatic Boussinesq equations and introducing simplifications appropriate to the boundary layer and the overlying stratified free atmosphere yield separate governing equations for the two regions. These are coupled through a dynamic boundary condition at the capping inversion, which directly captures the feedback of gravity waves on the boundary-layer flow. A mixed pseudo-spectral finite-difference discretisation yields a computationally efficient model while retaining vertical boundary-layer structure. For the semi-infinite wind farm considered here, a complete solution is obtained in a matter of seconds on a standard laptop. Comparisons with large-eddy simulations (LES) confirm the model successfully reproduces both internal wind-farm flow and large-scale gravity-wave effects. It captures the upstream blockage induced by adverse pressure gradients, as well as the accelerated wake recovery within and downwind of the farm, driven by favourable pressure gradients.

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Hossein A. Kafiabad, Majid Bastankhah. 2026-05-28. Two-way coupling of gravity waves and wind farm wakes: a reduced-order boundary-layer model. https://arxiv.org/abs/2605.30077

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