Aeroelastic problems are encountered at the preliminary design stage of flexible wings for large aircraft. A three-dimensional finite element model of a high-aspect-ratio wing was built, and the influence of the front...Aeroelastic problems are encountered at the preliminary design stage of flexible wings for large aircraft. A three-dimensional finite element model of a high-aspect-ratio wing was built, and the influence of the front and rear spar positions on the results of the aeroelastic analysis and optimization was studied to improve the wing structure desgin. The most feasible and optimal solutions were effectively obtained by aeroelastic optimization. In particular, the position parameter of the front spar has a greater influence on the aeroelastic analysis and optimization than the rear spar. In addition, some key constraints became re- strictive leading to a rapid increase in the structural weight. Therefore, reasonable constraints were necessary for the optimization of results.展开更多
In this paper,a coupled CFD-CSD method based on N-S equations is described for static aeroelastic correction and jig-shape design of large airliners.The wing structural flexibility matrix is analyzed by a finite eleme...In this paper,a coupled CFD-CSD method based on N-S equations is described for static aeroelastic correction and jig-shape design of large airliners.The wing structural flexibility matrix is analyzed by a finite element method with a double-beam model.The viscous multi-block structured grid is used in aerodynamic calculations.Flexibility matrix interpolation is fulfilled by use of a surface spline method.The load distributions on wing surface are evaluated by solving N-S equations with a parallel algorithm.A flexibility approach is employed to calculate the structural deformations.By successive iterations between steady aerodynamic forces and structural deformations,a coupled CFD-CSD method is achieved for the static aeroelastic correction and jig-shape design of a large airliner.The present method is applied to the static aeroelastic analysis and jig-shape design for a typical large airliner with engine nacelle and winglet.The numerical results indicate that calculations of static aeroelastic correction should employ tightly coupled CFD-CSD iterations,and that on a given cruise shape only one round of iterative design is needed to obtain the jig-shape meeting design requirements.展开更多
This paper presents studies of aeroelastic optimization on composite skins of large aircraft wings subject to aeroelastic constraints and strength/strain constraints. The design variable for optimization was the ply t...This paper presents studies of aeroelastic optimization on composite skins of large aircraft wings subject to aeroelastic constraints and strength/strain constraints. The design variable for optimization was the ply thickness of the wing skin panels, and the structural weight was the objective function to be minimised. The impacts of three strength/strain constraints and the ply proportion of the wing skin panels on the optimization results are discussed. The results indicate that the optimal composite wings that satisfy different constraints have remarkable weight advantages over metal wing. High levels of stiffness can be achieved while satisfying the constraints regarding allowable design strains and failure criteria. The optimization results with variable-proportions indicate that wing skins with higher proportions of 0° plies from the root to the middle segment and ±45° plies outboard have a more efficient and reasonable stiffness distribution.展开更多
基金supported by the National Natural Science Foundation of China (Grant No.10902006)the Doctoral Program Foundation of Institutions of Higher Education of China (Grant No.20091102110015)
文摘Aeroelastic problems are encountered at the preliminary design stage of flexible wings for large aircraft. A three-dimensional finite element model of a high-aspect-ratio wing was built, and the influence of the front and rear spar positions on the results of the aeroelastic analysis and optimization was studied to improve the wing structure desgin. The most feasible and optimal solutions were effectively obtained by aeroelastic optimization. In particular, the position parameter of the front spar has a greater influence on the aeroelastic analysis and optimization than the rear spar. In addition, some key constraints became re- strictive leading to a rapid increase in the structural weight. Therefore, reasonable constraints were necessary for the optimization of results.
基金supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘In this paper,a coupled CFD-CSD method based on N-S equations is described for static aeroelastic correction and jig-shape design of large airliners.The wing structural flexibility matrix is analyzed by a finite element method with a double-beam model.The viscous multi-block structured grid is used in aerodynamic calculations.Flexibility matrix interpolation is fulfilled by use of a surface spline method.The load distributions on wing surface are evaluated by solving N-S equations with a parallel algorithm.A flexibility approach is employed to calculate the structural deformations.By successive iterations between steady aerodynamic forces and structural deformations,a coupled CFD-CSD method is achieved for the static aeroelastic correction and jig-shape design of a large airliner.The present method is applied to the static aeroelastic analysis and jig-shape design for a typical large airliner with engine nacelle and winglet.The numerical results indicate that calculations of static aeroelastic correction should employ tightly coupled CFD-CSD iterations,and that on a given cruise shape only one round of iterative design is needed to obtain the jig-shape meeting design requirements.
文摘This paper presents studies of aeroelastic optimization on composite skins of large aircraft wings subject to aeroelastic constraints and strength/strain constraints. The design variable for optimization was the ply thickness of the wing skin panels, and the structural weight was the objective function to be minimised. The impacts of three strength/strain constraints and the ply proportion of the wing skin panels on the optimization results are discussed. The results indicate that the optimal composite wings that satisfy different constraints have remarkable weight advantages over metal wing. High levels of stiffness can be achieved while satisfying the constraints regarding allowable design strains and failure criteria. The optimization results with variable-proportions indicate that wing skins with higher proportions of 0° plies from the root to the middle segment and ±45° plies outboard have a more efficient and reasonable stiffness distribution.
