WEATHER RESISTANCE EVALUATION TEST OF EROSION SHEETS FOR WIND TURBINES

Abstract

To study weather resistance of erosion sheets for wind turbine blade in snowy cold regions, a water spray adhesion tester, a rotating ice adhesion force tester, and a special erosion wind tunnel have been developing. In the water spray test, in a constant temperature laboratory cooled to -20 °C, a water sprayer (droplet diameter assuming raindrops = 270-450 μm) was driven and a test erosion sheet (150 mm × 150mm) is splayed with the spray water and ice-accreted. This ice-accreted sheet is rotated at ~3000 rpm in the rotation test apparatus having a diameter of 400 mm, and the ice-accretion force is determined from the centrifugal force when the ice is blown off. In the special erosion wind tunnel, sand and snowflakes collide with the test sheet at a speed higher than the blade tip relative velocity (50m/s~) of a 3.3MW wind turbine at average wind speed, and the state of the sheet surface is investigated. The outline of the development of each test equipment is reported.