Improvement in ice tolerance of swept wing based on variable drooping leading edge

The contradiction between the efficiency and the ice tolerance remains a challenge to the traditional aerodynamic design considering the icing effect. To address the problem, a new ice-tolerant concept based on the variable drooping leading edge is proposed and extended to a single-aisle commercial aircraft with the swept wing. The outer-wing and full-spanwise drooping leading edge configurations are set up to distinguish the effect of different ice tolerant strategies. The Reynolds-averaged Navier-Stokes results reveal that the stall angle of attack is delayed by 25.0%, and the maximum lift coefficient is increased by 23.3% with the full-spanwise drooping in the presence of horn-shaped ice on the wing. This improvement is primarily driven by the recovery of leading-edge suction. With the formulation of the improved delayed detached eddy simulation, the structures and the behaviors of the separated flow near the stall point are analyzed via the comparison before and after drooping the leading edge in full-spanwise. The results indicate that the suppression of the spatial development of the shedding shear layer promotes the closure of the separation bubble and mitigates the sweeping motion of the large-scale spanwise vortex. These integrated effects contribute to the enhancement of ice tolerance.