Optimization of Supercritical Airfoil Considering the Ice-Accretion Effects

Abstract

Ice formation on a wing poses threats to aircraft safety because it changes the effective shape of the airfoil and deteriorates its lift and moment performances dramatically. The present study develops a supercritical airfoil optimization design method that takes into account the ice-accretion effects. A multipoint/multiobjective aerodynamic optimization tool based on a response surface-enhanced evolutionary algorithm and a Reynolds-averaged Navier–Stokes analysis is constructed. A modified shear stress transport turbulence model is developed for predicting the stall behavior of an airfoil with a non-streamline leading-edge caused by horn-shaped ice. The aerodynamic coefficients of the design points at high-speed/low-speed/ice-accretion situations are set as the collaborative objectives. Pressure distribution constraints are applied to assure favorable pressure distribution, and they better coordinate these objectives. The results show that the present optimization improves the maximum lift coefficient of an iced airfoil by 16.5% while maintaining the cruise aerodynamic efficiency as well as its robustness. The selection of design objectives is discussed to achieve better design quality and efficiency. The optimized airfoil is analyzed with different ice shapes as well as icing conditions, and it is applied on a wing, which validates the improvement of aerodynamic performance.