LES Study of Wake Meandering in Different Atmospheric Stabilities and Its Effects on Wind Turbine Aerodynamics

摘要: Wake meandering disturbs the stability of far wake field and thus increases fatigue loads downstream wind turbines. A deep understanding this phenomenon under atmospheric boundary layers its relation to structural helps better model dynamic alleviate adverse effects. large eddy simulation an actuator line are introduced in present work simulate aerodynamic turbines with different longitudinal spacings. By temporal filtering gaussian fitting method, center edge precisely defined, characteristics, including width, oscillation amplitude, frequency, described based on statistical data simulated flow field. Results reveal that is caused by both large-scale structure unstable vortex shed from rotor because two distinct frequency ranges detected. As atmosphere instability increases, former becomes dominant inducing factor movements. Further, analysis correlation between inflow characteristics deflection shows Taylor hypothesis remains valid within a distance over thousand meters neutral convective layers, proving feasibility using for evolution prediction. In addition, our study fluctuation blade root moment yaw significantly intensified wake, their standard deviation augmenting times conditions. The power spectrum illustrates component rotation sensible effect, but latter, density all frequencies increased wake. These indicate will be underestimated without considering effect. Moreover, high implies we can predict incoming information accuracy.