The effects of isotropic homogeneous flexibility on the aerodynamic performance of flapping
wings with different shapes and aspect ratios in hover at a Reynolds number of 400 have
been studied numerically with a 3-D Navier–Stokes solver coupled with a structure solver.
Three wing shapes, defined by the radius of the first moment of wing area, r 1¯(= 0.43, 0.53
and 0.63), with four aspect ratios, AR (= 1.5, 2.96, 4.5 and 6.0) are considered. We used a
set of moderately flexible wings with an effective stiffness of 14 and 2.31 (for the mass ratio …