Boxfish and Delta Wings: A Parametric Study of the Effect of Thickness Distribution on Delta Wing Stability*

Delta wing aircraft aerodynamics are largely characterized by twin vortices that shed from the leading edge of the wing. These leading edge vortices (LEVs) are also observed in nature on several bony fishes in the Ostraciidae family known as boxfishes. Obvious differences in these two geometries raise questions about the impact of geometry on the growth and development of the LEV and subsequent impacts on aero/hydro-dynamic performance and stability. In particular, what influence does the contour of the top surface of a delta wing have on the development of the LEV over the body? How can the geometry of the upper surface/fuselage be tailored to yield desirable aerodynamic characteristics? Additionally, these questions are relevant to a growing debate in the literature about the hydrodynamic function of boxfishes’ hard outer shells as they pertain to swimming dynamics. Hydrodynamic stability and performance of a range of delta wing geometries will be characterized in a novel water tunnel. Initial dye visualizations will inform particle image velocimetry (PIV) and force balance data collection.

This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1745301 and the Center for Autonomous Systems and Technologies at the California Institute of Technology.