【作者】 张玉良；

【导师】 程兆雪；

【作者基本信息】 兰州理工大学 ， 流体机械及工程， 2006， 硕士

【摘要】 随着社会的发展,能源需求日益增大,同时又面临环境保护问题。目前,利用水平轴风力机发电是风能利用的主要形式,以解决上述问题。风轮是风力机的关键部件,其空气动力学计算是风力机研究的基础,在此基础上寻求提高风力机风轮的气动性能的途径以便实现开发大型风力发电设备的主要目的。因此,风轮的空气学计算的原理与方法即成为风力机研究的主要问题之一。 在简单分析了国内外风电开发现状,尤其是风力机气动研究现状之后,对几种常用的风力机空气动力学设计理论做了详细的介绍,并且把这几种设计理论做了对比。同时还对风力机风轮气动性能研究的最新进展进行了归纳,主要表现为风力机专用翼型气动性能的研究,利用振荡射流提高风力机翼型气动性能的研究和利用增加局部粗糙度增加叶片升力的研究,为下一步的研究提供了借鉴。 “设计风速”这一参数在风轮气动计算中是一重要参数。根据风速分布函数,采用不同的数学形式的无穷远来流沿垂直高度变化的风速切面分析与计算风轮扫掠面积上产生的风功率。计算结果都证实采用风轮中心(即轮毂处)的风速作为风轮设计风速是相当合理的,不用考虑风切面的形状影响。 最后对目前常用的计算流体力学的商用软件做了说明,并且根据风力机的实际情况,建立合理的流动模型。接着利用FLUENT软件对风轮流场进行数值模拟。然后对模拟结果进行了分析,以便获得风轮后尾流中的螺旋形涡系。计算结果证明,CFD法为风力机的气动研究提供了有益的帮助。随着计算机的发展以及湍流模型的不断完善,计算流体力学方法必将成为风力机气动性能计算的发展趋势。更多还原

【Abstract】 With the development of society, energy demand is ever-increasing. At the same time, we are also facing to the problem of protection from environment pollution. At present, adopting horizontal-axis wind machine to generate electricity is the main form of use of wind energy to deal with above problem. The rotor of wind machines is its key assembly, and its aerodynamic calculation is the investigation basis of wind machine. Seeking approachs to improving aerodynamic characteristics of wind machine rotor is the primary aim of developing large-scale electricity generation with wind equipment. Thus, the theory and means of aerodynamic calculation of wind turbine is one of main problems in wind machine investigation.After briefly analyzing the wind power exploitation, especially the aerodynamic investigation of wind machine, at home and abroad several wind machine aerodynamic design theories in common use are introduced in detail and compared to each other. Meanwhile, the up-to-date evolvement of aerodynamic investigation of wind turbine rotor is summed up, including the research of aerodynamics characteristic of special aerofoils for wind machine, the oscillatory spray improves the performance of wind machine aerofoils and increase local roughness of surface of the aerofoils to improve their lift, providing reference to further investigation of wind machine."Design wind speed" is an important parameter in aerodynamic calculation of wind machines. According to wind speed distribution function, the wind power produced by the which passes through wind the rotor on swept area is analysed and calculated. The calculation results confirms that the wind speed at the rotor center can be taken as the design wind speed, and the aerodynamic design of the rotor will be fairly reasonable without consideration of the form influence of wind shear section.Finally, commercial softwares of computational fluid dynamics commonly used for wind machine investigation are explained in detail. According to the actual development condition of wind machine, the geometry of flow region is reasonably modeled, numerical simulation is conducted with software FLUENT. Then the simulation result is analysed and vortex system in the rotor is obtained. It is verified by the numerical result that CFD can offer useful help for aerodynamic investigation of wind machine. With the development of computer technology and further improvement of turbulence modeling, CFD will certainlybecome the development tendency of aerodynamic calculation of wind machine.更多还原