Experimental study on icing and anti-icing of a rotating conical spinner

Abstract

Icing and hot-air anti-icing tests of a rotating conical spinner were carried out in an icing wind tunnel. The surface temperature was measured using a calibrated infrared thermal imager. The icing process and the water film flow on the spinner were recorded by a high-speed camera. In the icing test with temperature of −21.7 °C and LWC (liquid water content) of 0.5 g/m3, white rime ice grows and covers the entire surface. From the cone tip the ice thickness decreases from 5.8 mm to a minimum of 3.2 mm, while in the rear part the ice thickness increases. In the icing test with temperature of −9.4 °C and LWC of 1.0 g/m3, long pine needle-shaped ice forms downstream the cone tip area. The anti-icing surface temperature first increases and then decreases along the spinner generatrix, with a maximum value near the tip. Under nearly identical incoming flow conditions the higher the mass flow of hot air is, the greater the decrease in surface temperature is. For the anti-icing tests with LWC of 0.5 g/m3, from t = 40 s, as the mass flow of the hot air is low the spinner surface is completely covered by water film. There exists a complete evaporation area near the cone tip with a high mass flow. For the anti-icing tests with LWC of 1.0 g/m3, from t = 40 s the spinner surface is completely covered by water film in all test runs.