Blended wing-fuselage frame made of fiber reinforced resin composites

摘要

A unitary frame having a central, annular-shaped fuselage section and a pair of outwardly opposed wing spars is fabricated from fiber- reinforced, resin matrix composites, and constitutes one of a number of similar such frames that are assembled together to form a framework of an aircraft body. Each wing spar has the general configuration of an I-beam incorporating a sine wave shear web reinforced along the upper and lower edges by flanges and lengthwise extending, tension/compression chords formed by bundles of lengthwise oriented fibers. The fuselage section has a circumferentially oriented sine wave shear web that is otherwise similar to the web of the wing spars, and has inner and outer circumferentially extending flanges that are similar to the upper and lower flanges along the wing spars. The root of each wing spar is joined to the respective side of the fuselage section by continuing the tension/compression chords into the fuselage section and by inserting a transition structure, in the form of a lightweight honeycomb core sandwiched between a pair of facing panels, at the juncture between the root of the wing spar and the fuselage section. The transition structure efficiently reacts loads developed along the tension/compression chords due to bending of the wing spar, and geometrically blends vertically oriented corrugations in the wing spar web with radially oriented corrugations in the web of the fuselage section.