Experimental and numerical investigation of an aircraft wing with hinged wingtip for gust load alleviation

Abstract

A recent consideration in aircraft design is using hinged wing tip devices to increase the aspect ratio, improving aircraft performance. Moreover, numerical studies have suggested using the wingtips during flight to provide additional gust load alleviation ability. This work aims to experimentally validate aeroelastic models of a wing with fixed and hinged wingtips. Validated numerical models of wings with hinged wingtips are essential to improve predictions and system knowledge and as a reference model for design optimisation. An elastic wing with hinged and fixed wingtips with different weights was tested. Static wind tunnel tests confirmed the ability of hinged wingtips to reduce gust loads. Aeroelastic models of the wing with the manufactured wingtips were developed, and time history gust responses validated the models. The validated models drove the design of a more efficient wingtip, which experimentally proved the improvement of load alleviation by reducing its mass and structural inertia. Based on this, a parametric study highlighted that increasing the wingtip mass alone, reducing the spanwise distance of the wingtip centre of mass from the hinge, or reducing the hinge stiffness reduces the maximum wing root bending moment.