Effect of Simulated Scalloped Ice on the Aerodynamics of a Swept-Wing at Low-Reynolds Number

Sandhu, Navdeep ; Soltani, Mohamad Reza ; Bragg, Michael B ; Lum, Christopher W ; Woodard, Brian S ; Broeren, Andy P ; Lee, Sam

关键词: LOW REYNOLDS NUMBER;    SWEPT WINGS;    AERODYNAMICS;    ICE FORMATION;    FLOW VISUALIZATION;    AIRCRAFT PERFORMANCE;   

RP-ID  :  GRC-E-DAA-TN55786

学科分类：航空航天科学

美国|英语

来源: NASA Technical Reports Server

【 摘 要 】

This paper studied the aerodynamic effects of a single scalloped ice accretion and two lower fidelity ice-shape simulations. These data were compared to the aerodynamics of a clean 8.9% scale CRM65 semispan wing model at a Reynolds number of 1.6 x 10(exp 6). The clean wing experienced an aggressive, tip-first stall and showed a small, strong leading-edge vortex at lower angle-of-attack while the iced cases showed larger, seemingly weaker leading-edge vortices at similar angles. The size of these vortices is larger for the low-fidelity ice shape. The stall pattern for the iced cases was also tip-first, but more gradual than the clean wing. The high-fidelity ice shape produced streamwise flow features over the upper surface of the wing due to flow moving through gaps that exist in the ice shape geometry that disrupted the formation of the leading-edge vortices, changing the aerodynamics of the wing. These gaps do not exist in the low-fidelity shape. The low-fidelity scallop ice shape was non-conservative in its aerodynamic penalties compared to the full high-fidelity case.