Aeroelastic tailoring of an NLF forward swept wing DLR contribution to LuFo IV joint research project AeroStruct

摘要

This article introduces the application of a mul-tidisciplinary analysis process chain based on high-fidelity simulation methods for the aeroelastic tailoring of an natural laminar flow (NLF) forward swept wing. With this approach the interactions between aerodynamics, loads and structural sizing are considered in the wing analysis. The resulting process enables an integrated aerostructural wing design including aeroelastic tailoring using carbon fiber reinforced plastics. The main feature of the process chain is the hierarchical decomposition of the problem into two levels. On the highest level, the orthotropy direction of the composite structure will be analyzed. The lower level includes the wing box sizing for essential load cases considering the static aeroelastic deformations. Thereby, the wing box sizing can be performed with a given ply share of the laminate or a ply share optimization. Additionally, the airfoil shapes are transferred from a given NLF wing design. The natural laminar flow is considered by prescribing laminar-turbulent transition locations. The process chain evaluates the wing mass, the lift-to-drag ratio under cruise flight conditions and the corresponding design mission fuel consumption. Results of aerostructural wing design studies and optimizations are presented for an NLF forward swept wing aircraft configuration. The aerostructural wing optimization with 3 orthotropy angles as design parameters shows a wing mass reduction in the order of 8% and a design mission fuel consumption reduction in the order of 4% in comparison to the aeroelastic tailored wing design of the reference aircraft.