Aeroelastic Stability and Performance Characteristics of Aircraft with Advanced Composite Sweptforward Wing Structures.

摘要

Sweptforward metallic wings have not been considered to be a serious design concept for nearly thirty years. The large structural weights necessary to preclude aeroelastic divergence of metallic wing structures are unfavorable when compared to similar sweptback designs, designs that are usually divergence free. The development of fibrous laminated composite materials and the fact that forward swept wings may have superior aerodynamic performance has led to renewed interest in this design. In this report, laminated beam theory, together with aerodynamic strip theory, is used to predict the static aeroelastic divergence characteristics of swept wings. From the results of this theory, it is predicted that, because of elastic coupling between bending and torsional deformation of the wing box, laminated composites may be used to preclude wing divergence for a large range of wing forward sweep angles. Formulas are developed to illustrate the important parameters governing composite wing divergence. Two examples are presented to illustrate the use of these formulas. These examples show that composite forward swept wings have the potential to be feasible, efficient designs. (Author)