Aerodynamic optimization and validation of a 3D wing in ground effect

Abstract

Ground effect significantly enhances the aerodynamic efficiency and lift-to-drag characteristics of aircraft. In nature, the Brown Pelican demonstrates superior seaskimming capabilities, deftly exploiting ground effect while following wave contours to minimize energy consumption during flight. Inspired by this biological mechanism, this study conducts bio-inspired design and aerodynamic shape optimization for Wing-in-Ground (WIG) crafts, based on the extracted geometric features of the Brown Pelican wing. A hybrid optimization strategy is proposed, employing a Genetic Algorithm (GA) for a preliminary search within the global design space, followed by a gradient-assisted algorithm for local refinement. The core objective of this optimization is to minimize the induced drag coefficient. Numerical simulations indicate that under Out-of-Ground-Effect (OGE) conditions, the induced drag coefficient of the optimized wing is reduced by 14%; conversely, under strong In-Ground-Effect (IGE) conditions at a height of 0.1 m, the reduction reaches as high as 90.05%.