The three-dimensional flows in the Weis-Fogh mechanism are studied by flow visualization and numerical simulation by the discrete vortex method. The vortex method, especially the vortex stick method, is employed to investigate the vortex structure in the wake of the two wings. The pressure is estimated by the Bernoulli equation, and the lift on the wing is also obtained. For the results, the eddies near the leading edge of each wing in the fling stage take a convex shape because the eddies shed from both tips entrain the flows, and the downwash in the rotating stage is deflected toward the outside because the outside tip vortex is stronger than the inside one. The lift coefficient on the wings in this mechanism is almost independent of the Reynolds number.
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This paper was recommended for publication in revised form by Associate Editor Haecheon Choi
Ki-Deok Ro received his B.S. degree in Marine Engineering from Pukyong National University, Korea, in 1977. He then received his M.S. and Ph.D. degrees from Kobe University, Japan, in 1986 and 1989, respectively. Dr. Ro is currently a Professor at the School of Mechanical Engineering at Gyeongsang National University in Gyeongnam, Korea. He serves as an Editor of Journal of the Korean Society of Marine Engineering. Dr. Ro’s research interests include fluid mechanics, CFD, and vortex method.
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Ro, KD. Three dimensional aerodynamic characteristics of weis-fogh mechanism. J Mech Sci Technol 23, 262–268 (2009). https://doi.org/10.1007/s12206-008-0750-9
- Computational fluid dynamics
- Vortex method
- Unsteady flow
- Vortex method
- Random walk method