Anti-Icing Coatings for Wind Turbine Blades Part 1: Preparation and Performance Testing

Ice coating on wind turbine blades poses a serious threat to the operation safety of wind farms, resulting in loss of power generation. The super hydrophobic coating is favored by the wind power operation department due to its convenient implementation and low cost, but its application in wind turbine blades is restricted due to its poor wear and weather resistance and limited anti icing effect. This paper proposed a preparation method of superhydrophobic coating with good wear and weather resistance and conductivity, which can realize the synergistic effect of "electric heating+superhydrophobic" and greatly improve the effect of anti icing and deicing. Carbon nanotubes are oxidized and inorganic substances are added to make them have better dispersibility in anhydrous ethanol solution. Cetyltrimethoxysilane is used to modify nanoparticles with low surface energy. Fluorocarbon resin is the most primer. Electrothermal superhydrophobic coatings are prepared by precipitation method. The hydrophobic property, electrothermal property and durability of the prepared coating were tested, and the test results are as follows: When the mass fraction of carbon nanotubes is 16.8%, it is because the content of carbon nanotubes increases and the dispersion is not uniform enough, and the static contact angle is 148°. When the mass fraction of carbon nanotubes is 13.2%, 9.3%, 9%, 7.7% and 7%, the static contact angle of the coating is 151°~162°, and the sliding angle is 4.3°~7.6°. The square resistance test results show that the conductivity of the coating is 0.5~12.5 S/m, and the conductivity of the coating decreases with the decrease of the content of carbon nanotubes in the coating. The wear resistance test shows that the wear amount of the coating is very small after 160 times of wear, the conductivity decreases from 0.50 S/m to 0.48 S/m, the value basically remains unchanged, the contact angle is stable at about 158°, and the sliding angle is smaller than 5°. After 120 h UV aging, the static contact angle of the coating basically remained unchanged, and the sliding angle slightly increased, but still smaller than 10°. The acid and alkali resistance test shows that the static contact angle of the coating samples dipped in the acid rain solution with pH=5 for 14 days decreases slowly and then tends to be stable, but still bigger than 150°, and the rolling angle rises slightly but smaller than 10°. The contact angle of the sample dipped in alkaline rain solution with pH=9 decreased by 5.2° after 14 days, and the rolling angle increased slightly as acid solution eroded, but no obvious regular change was smaller than 10°. After soaking in alkaline solution, the static contact angle of the coating decreases greatly, and the corrosion ability of alkaline solution to the coating is stronger. The coating adhesion and durability under icing environment were tested. The icing bond strength test of the coating revealed that its icing lateral bond strength was less than 38.4 kPa. After 2 days of ice coating, the static contact angle of the coating is still bigger than 150°, but the sliding angle is bigger than 10°, and the superhydrophobic property is lost. After 3 days of icing, the static contact angle decreases from 150° to 101°, and the sliding angle is bigger than 90°. After 5 cycles of "icing - deicing", the static contact of the coating drops to 150.6°, and the sliding angle is still bigger than 90°. The main reason for the significant increase of the sliding angle of the coating is the destruction of the micro nano rough structure of the coating surface by ice coating. © 2023 Chinese Machine Press. All rights reserved.