风机叶片电加热除冰及电阻丝布置方式试验研究

Experimental Study on De-icing and Layout of Resistance Wire by Electrical Heating for Wind Turbine Blades

为研究外界因素对风机叶片电阻加热除冰时间的影响规律,以及电阻丝布置方式对融冰过程的影响,该文在多功能人工气候室内对风机叶片进行了电阻加热除冰试验研究,分析了覆冰厚度、环境温度、相对风速和液态水含量(liquid water content,LWC)对除冰时间的影响规律,并提出了合理的电阻丝布置方式。结果表明:覆冰厚度较小时,其对除冰时间的影响较为明显,随着覆冰厚度的继续增大,除冰时间无明显差异;除冰时间随加热功率和环境温度的增大而降低,随相对风速和LWC的增大而增大,且不同覆冰厚度下除冰时间随上述因素的变化曲线会有较大不同;叶片尖部电阻丝宜采用弦向布置,根部电阻丝宜采用展向布置;除冰过程中,叶片尖部冰层易发生脱落,根部冰层易被融化。

To research the influence rule of external factors on de-icing time and the influence of resistance wire arrangement on the process of ice melting for wind blade by electrical heating, electrical heating de-icing experiments were conducted in artificial climate chamber. The influence rule of ice thickness, environment, temperature, relative wind speed and liquid water content （LWC） on de-icing time was analyzed, and a reasonable way of resistance wire arrangement was put forward. Test results show that the effect of ice thickness on de-icing time is more obvious when ice thickness is small, with the increase of ice thickness, there will be no obvious difference on de-icing time; De-icing time decreases with the increase of heating power and environment temperature and increases with the increase of relative wind speed and LWC, in addition, the de-icing time curve along with the change of above factors are quite different under different ice thickness; Chordwise layout of resistance wire is applied on front site of blade and spanwise layout of resistance wire is applied on root of blade; The ice on front site of blade is easily fell off while remaining ice is easily melt.