A Numerical Study of Bio-Inspired Flight for Martian Exploration

Abstract: Aircraft with bio-inspired flapping wings operated in low-density atmospheric environments encounter unique challenges associated with the low density. The low density leads to the high operating velocities of aircraft for generating sufficient lift, resulting in significant compressibility effects. Here we perform numerical simulations to investigate the compressibility effects on the lift generation of a bio-inspired wing during hovering using an immersed boundary method. Various wing planforms, kinematics and structural properties are considered in this paper. In this study, it has been identified that the dimensionless lift decays linearly with an increase in Mach number. This decay rate is a function of the Reynolds and Mach numbers, as well as the angle of attack and structural properties of the wing. This linear decay is attributed to the drastic change in the pressure on the wing surface caused by unsteady shock waves. It is also observed that the vortex structures of flexible wings approach those of rigid wings at sufficiently high Mach numbers due to the wing-vortex-shock interactions Keywords: Computational Fluid Mechanics, Bio Fluid Mechanics, Fluid-Structure Interaction, Vehicle Aerodynamics, Vortices