Preliminary study on flutter scaling of high-aspect ratio wings

Abstract

As a result of the increasing demand for aircraft performance, the high-aspect-ratio wing (HARW) becomes the primary structural type of the emerging aircraft as it improves the lift-to-drag ratio. However, HARWs result in higher deflections, leading to a geometrical nonlinear behavior and nonlinear aeroelastic problems. In this work, the preliminary study on aeroelastic behavior of two classic types of HARWs, namely, Goland wing and High Altitude Long Endurance (HALE) wing, are investigated. Aeroelastically scaled models using two scaling methods, called classic scaling method and modified scaling method, are applied and compared with each other. Froude number is considered in the modified scaling method. Both static aeroelastic and flutter analyses are conducted on each scaled model by using different scaling methods. The results show that the Froude number is important to the HALE wing, where both static deflects and flutter velocity obtained by the scaled model agree well with the full model when the Froude number similarity is met. Thus, the Froude number may be the key similar parameter for the HALE wing scaling model design. For the Goland wing scaling model, the Froude number could be ignored.