Research on Normal Ice Adhesion Strength in Icing Wind Tunnel

Abstract

Aircraft icing jeopardizes flight safety seriously. The design of aircraft anti-icing/de-icing systems requires adequate knowledge of the adhesion between the ice and the substrate. In this research, an experimental device that can be accommodated in a wing is designed and constructed. Simulation analysis of the interfacial stresses is performed, which shows that increasing the load and the interface size impair the stress uniformity at the interface. In addition, the ice layer does not undergo cohesive damage during the tests. The normal ice adhesion strength is evaluated in an icing wind tunnel using the test system in this paper. For glaze ice, the normal adhesion strength increases with lower temperature, while the trend is reversed for rime ice. The minimum adhesion strength occurs near the medium volume diameter (MVD) of 30 µm. Furthermore, the normal strength is significantly enhanced by the increase in wind speed and surface roughness as well as by surface painting. The adhesion strength of aluminum substrates to ice was greatest compared to titanium and stainless steel. Compared to shear adhesion strength, normal adhesion strength is less sensitive to various influencing factors. The proposed experimental framework enables precise measurement of normal adhesion strength of impact ice in the icing wind tunnel.

Keywords: Aircraft de-icing, Normal adhesion strength, Experimental setup, Impact ice, Icing wind tunnel