Computational Analysis of Low Reynolds Number Couette Flow Over an Embedded Cavity Geometry

A butterfly utilizes an efficient and complex flight mechanism comprised of multiple interacting flow control devices that include flexible, micro-geometrically surface patterned, scaled wings.~ The following research attempts to deduce any aerodynamic advantages that arise from the formation of vortices in between successive rows of scales on a butterfly wing.~ The simplified computational model consists of an embedded cavity within a Couette flow with the flat plate moving transversally over the cavity. ~The effects of cavity geometry and Reynolds number are analyzed separately.~ The model is simulated in ANSYS FLUENT and provides qualitative insight into the interaction between the scales and the boundary layer.~ Preliminary results indicate that vortices form within the cavity and potentially contribute to a net partial slip condition.~ Further, the embedded cavities contribute to a net reduction in the drag coefficient that varies with Reynolds number and cavity geometry.~