Taguchi Robust Design of a Wind Shear Mitigation Fence to Enhance Wind Turbine Efficiency

Abstract

This paper proposes an optimal design method, which consists of computational fluid dynamics and Taguchi robust design method, for a wind shear mitigation fence installed at the upstream of a wind turbine to reduce the fatigue load on the blades and to augment the power generation. The fence generates a virtual hill effect, which mitigates wind shear by speedup of the lower part of the atmospheric boundary layer. For the design factors, the fence height, fence inclination angle, separation distance between the fence and wind turbine, wind speed, and turbulence intensity of the upstream wind profile are considered by constructing a L9 Taguchi orthogonal array. For the performance measures, the wind speed-up within a rotor plane of wind turbine and non-uniformity of the wind speed profile were evaluated. The main design factors were the fence height in terms of power generation augmentation and the separation distance in terms of the fatigue load mitigation. In the case of a 5 m fence installation, a 2% increase in wind speed and 42% decrease in non-uniformity was anticipated so that the substitution of a solid fence with a more practical windbreak is likely to be considered.