Turbulence-resolving simulations of wind turbine wakes

TL;DR

This paper compares turbulence-resolving simulations of wind turbine wakes using static and dynamic spectral vanishing viscosity models, showing the dynamic approach better captures wake features with less over-dissipation.

Contribution

The study introduces and evaluates a dynamic spectral vanishing viscosity model for wind turbine wake simulations, improving accuracy over the static approach.

Findings

Dynamic iSVV adapts dissipation locally in space and time.

Static iSVV can become over-dissipative with increased viscosity.

Dynamic iSVV provides more accurate wake feature representation.

Abstract

Turbulence-resolving simulations of wind turbine wakes are presented using a high--order flow solver combined with both a standard and a novel dynamic implicit spectral vanishing viscosity (iSVV and dynamic iSVV) model to account for subgrid-scale (SGS) stresses. The numerical solutions are compared against wind tunnel measurements, which include mean velocity and turbulent intensity profiles, as well as integral rotor quantities such as power and thrust coefficients. For the standard (also termed static) case the magnitude of the spectral vanishing viscosity is selected via a heuristic analysis of the wake statistics, while in the case of the dynamic model the magnitude is adjusted both in space and time at each time step. The study focuses on examining the ability of the two approaches, standard (static) and dynamic, to accurately capture the wake features, both qualitatively and quantitatively. The results suggest that the static method can become over-dissipative when the magnitude of the spectral viscosity is increased, while the dynamic approach which adjusts the magnitude of dissipation locally is shown to be more appropriate for a non-homogeneous flow such that of a wind turbine wake.