Abstract: In order to study the noise problems of MW-size wind turbine blades， the objective function with the maximum power coefficient to noise was proposed based on BEM theory and noise calculation model under the giving work conditions. A mathematical optimal model was established， where the chords and twist angles were used as the design variables which might influence the noise performances of wind turbine blades. The actual design of a 2.3MW wind turbine blades was optimized. The optimal noise results were compared with the noise experimental data. The results show that the predicted noise values are agreed with experimental ones in the main frequency fields. Compared to the actual blades， the new blades have lower noise which the noise pressure level is reduced by 7.1%， and the power coefficients are also improved. The feasibility for the novel design method was verified.

Key words: wind turbine blade, aerodynamic noise, blade element momentum（BEM）, power coefficient

摘要： 针对目前兆瓦级风力机叶片噪声污染问题，基于动量叶素理论及叶片噪声计算模型，提出在给定工况条件下，以功率系数与噪声的最大比值为目标函数，以影响叶片气动噪声性能的弦长及扭角为设计变量，建立了低噪声风力机叶片优化设计数学模型。对某实际2.3MW风力机叶片进行优化设计，并与噪声实验数据对比，结果表明：在主要频率域范围内，叶片噪声预测值与实验数据较吻合；相比原叶片，新叶片具有更低的噪声特性，噪声声压级降低了约7.1%，同时风轮功率系数略有增大，从而验证了该设计方法的可行性。

关键词: 风力机叶片, 气动噪声, 动量叶素, 功率系数