考虑启动与失速特性的混合翼型小型风电叶片多目标气动优化

小型风电叶片气动特性是影响小型风力机整机性能的关键因素。针对小型风力机存在启动慢、效率低和高风失速不平稳等问题，本项目基于叶素动量理论，考虑涡流、叶梢损失和推力修正等，建立小型风力机叶片空气动力学模型；考虑年风速概率分布，建立年能量输出数学模型。考虑低雷诺数和大攻角因素的影响，进行翼型气动分析，研究混合翼型小型风力机叶片启动性能，建立混合翼型叶片启动修正模型。通过理论分析、数值模拟和实验数据分析等手段，研究混合翼型小型风力机叶片高风失速性能；基于现有失速延迟修正模型，考虑三维旋转效应的影响，建立混合翼型叶片失速延迟修正模型。通过混合翼型叶片全风速工况气动机理分析并基于多目标优化理论，形成低风启动、失速平稳和年能量输出最大的多目标叶片气动优化策略与方法。这对拓宽小型风力机工作风速范围、提高小型风力机能量输出和保障安全平稳运行和促进小型风电技术成熟发展具有积极意义。

The aerodynamic characteristics of small wind turbine blades are the most important factors of the whole small wind turbine system. Regarding to the poor starting performance, low power efficiency and instability of stall delay problems, based on the blade element moment theory, this project investigates the development of aerodynamic models of mixed-airfoil small wind turbine blades with consideration of wake, tip loss and thrust correction; an annual energy production mathematical model will be established with consideration of annual wind speed distribution. The starting performance of mixed-airfoil small wind turbine blades will be investigated; and a corrected aerodynamic model for starting will be established based on airfoil aerodynamic analysis including low Reynolds numbers and high angles of attack effects. Using theoretical analysis, numerical simulation and experimental data analysis, the stall performance of mixed-airfoil small wind turbine blades will be studied; with consideration of three-dimensional rotation effects, a corrected stall model will be built for mixed-airfoil small wind turbines based on the existed stall models. Based on the aerodynamic analysis of the whole wind speed range of mixed-airfoil small wind turbine blades and multi-objective optimisation theory, a multi-objective optimisation method of low start-up wind speed, stable stall and optimal annual energy production for mixed-airfoil small wind turbines will be proposed. This research is of significant importance for widening the range of operation wind speeds, maximisation of annual energy production, stale and safe operation of small wind turbines, and promoting to the mature development of small wind turbine technology.