风机叶片电加热防冰模型及分区防冰方法

Anti-icing Model and Sectionalized Anti-icing Method by Electrical Heating for Wind Turbine Blades

根据风机叶片电加热防冰结构和流场特点,并结合对覆冰条件下风机叶片表面能量交换过程的分析,建立了风机叶片电加热防冰理论模型,并对临界防冰状态进行了仿真分析;同时在人工气候室对理论模型进行了试验验证;另外提出了等差分区加热控制防冰方法。研究表明:不同叶片位置处的温升特性和临界防冰功率密度也不相同,随着旋转半径的增大,叶片表面温升速率下降,平衡温度降低,达到平衡温度所用时间缩短,临界防冰功率密度增大;防除冰结构的隔热层可以有效地阻碍热量向叶片内部传递,减少热量的损失;等差分区加热控制方法可以明显改善叶片表面的温度分布,降低叶片表面温差和能量消耗,具有工程实际意义。

According to the structure of anti-icing system and characteristics of flow field, and combined with the analysis of energy exchange process on blade surface under icing condition, the electrical heating anti-icing model was studied and established. The threshold anti-icing state was analyzed by simulation in this paper. Moreover, the theoretical model was verified by experiment in an artificial climate chamber. Meanwhile, a sectionalized anti-icing method was put forward. The researches show that：characteristic of temperature rise and threshold anti-icing power density is different with the location of blade, with the increase of the radius, the rate of temperature rise and the equilibrium temperature is decreased, the time used to attain the equilibrium temperature is shortened and threshold anti-icing power density is increased; Thermal insulation layer can effectively prevent heat transferring to the internal blade and reduce the loss of heat; Sectionalized anti-icing method can improve the distribution of temperature on blade obviously, reduce temperature difference and energy consumption, which possess the practical significance.