Efficient Global Optimization of Advanced Drop-Hinged Flap

Abstract

This paper proposes an improved design methodology and global optimization method for the design of an advanced dropped-hinge flap (ADHF) using an integrated approach. The approach implemented an actuation-driven parametric model for a hinged-flap concept. The optimization methodology incorporates an adaptive data sampling method in the update of a series of surrogate models. Inclusion of an actuation mechanism in the definition of the model eliminated a large number of gap and overlap settings that are not practically possible, leading to further savings in the number of computational fluid dynamic calculations required. Parameters for the actuation definition, flap geometries, and spoiler settings are included simultaneously in the optimization in order to consider the interactions among these factors and to obtain near-global-optimal solutions. Compared with a traditional sequential shape/mechanism optimization methodology, which can only produce one design point meeting the landing requirement, a series of design points can be obtained from the proposed methodology, meeting the requirements for both takeoff and landing configurations. The optimal result not only significantly improves at an angle of attack of eight by 17.8% but also decreases the distance between the hinge and the lower surface of the airfoil by 22.4%, which can reduce the fairing size. Comparisons are given between the optimized ADHF and the traditional Fowler flap, along with detailed analysis on the potential benefits by supplementing the design with spoiler deflections.