1. College of Energy and Power Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, P. R. China; 2. Key Laboratory of UAVs Advanced Technology(Nanjing University of Aeronatics and Astronautics), Ministry of Industry and Information Technlogy, Nanjing 210016, P. R. China
Under the condition of thermal anti-icing, the liquid water on the leading edge of the airfoil that would flow to the downstream non-protective zone will produce ridge ice, thus endangering flight safety. Based on the existing three-dimensional (3D) icing model which considers the water film flow on the ice layer, an icing model with thermal boundary condition is introduced. With the boundary conditions of none anti-icing and thermal anti-icing, glaze ice accretion and ridge ice accretion are simulated on a simplified airfoil of unmanned aerial vehicle(UAV), and then the lift coefficient and drag coefficient are calculated and compared with the smooth airfoil under the same conditions. The results show that the lift-drag ratio obviously decreases after glaze ice occurred on the leading edge under the condition of none anti-icing; and that after setting the condition of anti-icing heat flux in the impingement area, the glaze ice on the leading edge becomes thinner and the ridge ice occurs in the non-protective zone, so the airfoil with this icing characteristic gets a lower lift-drag ratio.
This work was financially supported by the Natural Science Foundation of Jiangsu Province (No.BK20150740),and the National Natural Science Foundation of China (No.51506084).
Guo Lingbo, Cao Guangzhou, Ji Honghu. Numerical Study on Ridge Ice Accretion and Its Effect Under Thermal Ice Protection[J]. Transactions of Nanjing University of Aeronautics & Astronautics,2018,35(5):770-777