The Experimental Research Of Erosion-Wear Process Of Wind Turbine Blade Coating By Wind-borne Sands

The frequent sandstorm phenomenon resulting wind turbine blade coating by erosion, so that the service life of a wind turbine blade severely shortened, which not only affects the safe operation, of wind farms and reduce the economic benefits of wind farms. In this paper, the method of accelerated wear is used to study the erosion of the surface coating of the wind turbine blade with glass fiber as the base. Researching the erosion wear rule of wind turbine blade coating under the action of wind-borne sands force, in order to clear erosion mechanism and establish the evaluation system based on the Bitter theory, provide a theoretical basis for improving wind turbine blade coatings anti-erosion ability.In this paper, the glass fiber is used as the base, and the polyurethane is used as the coating material to make the wind turbine blade sample. Using self-made XS-40 test bed and the sediment air injection method, do erosion wear tests on samples and real wind turbine blade. Were the single factor experiment of wind turbine blade sample and real wind turbine blades respectively. The erosion process of the coating was analyzed and the erosion morphology was observed by SEM. Found out the corrosion mechanism and establish the evaluation system based on the Bitter theory. Do orthogonal experiment for erosion rate, erosion angle and the sand amount to find out the optimal parameters of the erosion of wind turbine blade coating.The results show:erosion amount of the sample coating increases along with the increase of the sand amount, the linear relationship between the erosion amount and the erosion rate. When erosion angle a<30°, erosion amount increases with the increase of erosion angle, a>30°, erosion amount decreases with the increase of erosion angle. When the erosion angle α≈30°, erosion amount maximum, α≈90°, erosion amount minimum. The real wind turbine blade leading edge and the windward surface erosion are increasing with the increase of the sand amount, along with the erosion rate increases erosion is more intense. At same part of the wind turbine blade, the leading edge of the erosion amount is less than the amount of erosion wear. The erosion mechanism of low Angle (α<30°) of coating is mainly subjected to shear stress of plowing and cutting; and it mainly bears the extrusion of normal stress in the erosion process of high angle (a >60°). As the polyurethane is a plastic material, it has low strength and good toughness, the effect of cutting force is more obvious than normal stress, thus the erosion is more serious when erosion angle is low (a<30°). The major factor of affecting coating erosion is erosion rate, followed by is the sand amount, the minimum impact factor is erosion angle. So in the high-speed erosion, carrying more sand, erosion angle (α≈30°), the amount of erosion is the largest.