Aerodynamic performance analysis of the wavy wing with varying spanwise waviness characteristics*

Present research work aim to analyse the impact of varying spanwise waviness parameters (i.e wavelength and amplitude) on the aerodynamic performance of the rectangular aircraft wing. Performance of wavy wing model were compared with smooth (i.e baseline) wing model. For that purpose two wavy wing models were generated one with increasing waviness wavelength and amplitude from root to tip λ3050h510 and second one with decreasing waviness parameters from root to tip λ5030h105. Wing models were developed by using NACA0021 airfoil profile and simulation were performed at Reynolds number Re=1.2x10^5. Numerical simulations were performed at Angle of Attack (AoA) from 0 to 20^o with the interval of 4^o. Simulation results were validated against published experimental work. Computational Fluid Dynamics (CFD) simulation results reveal that, wavy wing lift performance degrade in pre-stall regime, whereas drag performance improved significantly. Additionally, lift and drag performance of wavy wing have shown substantial improvement in post stall regime. Results revealed that wavy wing model λ3050h510 performed better as compared wing model λ5030h105. It is estimated that, wavy wing model experience maximum decrement of 17.9% in lift at 4^o AoA, whereas 9.2% decrease in drag coefficient at 12^o AoA in comparison of baseline wing. Moreover, maximum increment of 16.3% in lift coefficient and 13.6% decrement in drag coefficient were noticed at 20^o AoA. Flow behavior analysis reveal that reduction in leading edge suction area results decrease in wavy wing lift performance, whereas restriction to the flow separation at waviness peak is the major reason behind increment in wavy wing performance in post stall regime. Moreover, it is hypothesis that use of wavy trailing edge is responsible for decrease in drag coefficient in pre-stall region.