Higher-Order Simulations of Flapping-Wing and Blade Aerodynamics Using Lattice Boltzmann Method

Speaker: Alex Povitsky, Department of Mechanical Engineering, University of Akron
October 5, 2015

Presentation

Abstract

Numerical model of aerodynamics of flapping wing in generalized pitching motion has been developed based on the high-order compact approximation of derivatives in Navier-Stokes equations, non-inertial coordinate system attached to the moving wing, and carefully tuned non-uniform grid. Comparison of numerical results for pitching and plunging wing with the experimental data at Re=10000 showed good qualitative agreement for the streamwise velocity and vorticity. Next, the aerodynamics of sets of flapping blades is explored for possible use in turbo-machinery compressors. The computational approach to model flapping blades in confined space is based on a novel particle-based kinetic Lattice Boltzmann method (LBM). Commercial LBM-based CFD software XFlow has been adopted to handle complex multi--body motion thus avoiding classic domain meshing needed by finite-volume computations. The user can control the local level of refinement of the underlying lattice in near-wing boundary layer and in street of vortices behind the wing. Selected values of governing parameters of single and paired flapping blades include blade profile and thickness, amplitude of plunging, angular amplitude of pitching, phase difference between plunging and pitching, distance between blades and phase difference between motions of two blades in parallel setting.

Biography

Alex Povitsky is an Associate Professor of Mechanical Engineering at the University of Akron, Akron OH. Prior to it he was Senior Scientist with the Institute of Computer Applications (ICASE) at NASA Langley Research Center, and then Associate Professor at Concordia University (Montreal). He published 50 journal papers in vorticity confinement approach, CFD modeling of micro- and nano- fluidics, development of parallel algorithms for implicit and high-order numerical schemes, modeling of laser ablation and hypersonic ablation, unsteady aerodynamics of micro air vehicles and aero-acoustics of vortex-body interaction using high-order schemes. His research has been supported by Canadian NSERC, British Royal Society, Israel Academy of Sciences, NSF, NASA, AFOSR, ARO, US Navy, ARDEC, AFRL, ASEE, industry and the State of Ohio. He is an Associate Fellow of AIAA. He has been an Air Force Summer Faculty Fellow in 2005-2009, 2011-2012 and 2014-2015.

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