大型风力机二维翼型气动性能数值模拟

NUMERICAL SIMULATION FOR PNEUMATIC CHARACTERISTICS FOR TWO-DIMENSIONAL AIRFOILS LARGE WIND TURBINE

运用先进的CFD软件FLUENT对大型风力机的主流商用二维FFA-W3-301和FFA-W3-211翼型的气动性能进行了数值模拟。采用了κ-ωSST湍流模型,并考虑了大入射攻角下失速现象的影响,对κ-ωSST湍流模型的内部关键参数进行了适当的修正,得到的升力系数和阻力系数模拟结果与风洞试验结果吻合很好;同时还进一步研究了这种翼型的升力系数与阻力系数对其表面粗糙度的敏感性,得到了该翼型对小粗糙度敏感性强的结论。综合结果表明,数值模拟技术是大型风力机翼型设计分析便捷有效的参考手段。

The pneumatic characteristics for two-dimensional FFA-W3-301 and FFA-W3-211 airfoil of large wind twbine were studied with the advanced CFD software, FLUENT. The k-ω SST turbulence model which is widely used in wind turbine computation was employed in the simulation, and considering influence of the turbulence separation at the surface of the airfoil, which happens in the large angle of attack, the parameters of the k-ω SST turbulence model were properly modified. The results for lift coefficient and drag coefficient obtained by numerical simulation coincide with the experi- mental data. Furthermore, the sensitivity of FFA-W3-301 airfoil to the surface roughness height was also studied, and as a result, the airfoil is very sensitive to small roughness height. Finally, the results suggest that the numerical simulation technique can become an economical and effective way for the design of large offshore wind turbine airfoils.