Multifidelity metamodel building as a route to aeroelastic optimization of flexible wings

Abstract

High-fidelity aeroelastic simulations of the response of flexible wings to a sudden gust can result in a huge computing effort, making the search for the best wing design prohibitively expensive. As an alternative, a cost-effective multifidelity metamodelling-based optimization strategy, where a metamodel of a high-fidelity aeroelastic simulation response is built by tuning a lower fidelity aeroelastic simulation response, is proposed. In order to address and validate such an approach, both linear and non-linear aeroelastic equations for an aerofoil employing different levels of complexity for expressing the aerodynamic load are used for the high- and low-fidelity models. An aeroelastic gust response evaluation problem is formulated for the flexible wing of a small unmanned air vehicle, whose characteristic size makes it particularly susceptible to gusts. Three different approaches to tune the low-fidelity model, both explicit and implicit, are investigated and compared. Good agreement between the high-fidelity model and the corrected low-fidelity one shows that the proposed approach is indeed suitable for optimization of the aeroelastic gust performance of flexible wings.