Direct numerical simulations of the flow around wings with spanwise waviness at a very low Reynolds number

• Published in: Computers & Fluids
• Main Authors: Serson, D, Meneghini, JR, Sherwin, SJ
• Other Authors: Engineering & Physical Science Research Council (E
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Elsevier 2017
• Subjects: Science & Technology; Technology; Computer Science; Interdisciplinary Applications; Mechanics; Incompressible flow; Spectral/hp methods; Flow control; NAVIER-STOKES EQUATIONS; FLIPPERS; Applied Mathematics; 0102 Applied Mathematics; 0913 Mechanical Engineering; 0915 Interdisciplinary Engineering; Humpback Whale
• Online Access: http://hdl.handle.net/10044/1/44058; https://doi.org/10.1016/j.compfluid.2017.01.013

Inspired by the pectoral flippers of the humpback whale, the use of spanwise waviness in the leading edge has been considered in the literature as a possible way of improving the aerodynamic performance of wings. In this paper, we present an investigation based on direct numerical simulations of the flow around infinite wavy wings with a NACA0012 profile, at a Reynolds number Re=1000Re=1000. The simulations were carried out using the Spectral/hp Element Method, with a coordinate system transformation employed to treat the waviness of the wing. Several combinations of wavelength and amplitude were considered, showing that for this value of Re the waviness leads to a reduction in the lift-to-drag ratio (L/D), associated with a suppression of the fluctuating lift coefficient. These changes are associated with a regime where the flow remains attached behind the peaks of the leading edge while there are distinct regions of flow separation behind the troughs, and a physical mechanism explaining this behaviour is proposed.