Browsing by Author "LAI, FM"

Now showing 1 - 3 of 3

DESIGN OF LAMINATED COMPOSITE PLATES FOR OPTIMAL DYNAMIC CHARACTERISTICS USING A CONSTRAINED GLOBAL OPTIMIZATION TECHNIQUE
(1995-02-01)
KAM, TY
;
LAI, FM
;
交大名義發表
;
機械工程學系
;
National Chiao Tung University
The lamination arrangements of moderately thick laminated composite plates for optimal dynamic characteristics are studied via a constrained multi-start global optimization technique. In the optimization process, the dynamical analysis of laminated composite plates is accomplished by utilizing a shear deformable laminated composite finite element, in which the exact expressions for determining shear correction factors were adopted, and the modal damping model constructed based on an energy concept. The optimal layups of laminated composite plates with maximum fundamental frequency or modal damping are then designed by maximizing the frequency or modal damping capacity of the plate via the multi-start global optimization technique. The effects of length-to-thickness ratio, aspect ratio and number of layer groups upon the optimum fiber orientations or layer group thicknesses are investigated by means of a number of examples of the design of symmetrically laminated composite plates.
MAXIMUM STIFFNESS DESIGN OF LAMINATED COMPOSITE PLATES VIA A CONSTRAINED GLOBAL OPTIMIZATION APPROACH
(1995)
KAM, TY
;
LAI, FM
;
交大名義發表
;
機械工程學系
;
National Chiao Tung University
The optimal lamination arrangements of laminated composite plates with maximum stiffness subject to side constraints are investigated via a constrained multi-start global optimization approach. In the optimal design process, the deformation analysis of laminated composite plates is accomplished by utilizing a shear deformable laminated composite finite element and the optimal design problem, which has been converted into an unconstrained minimization problem via the general augmented Lagrangian method, is solved by utilizing the proposed unconstrained multi-start global optimization technique to determine the optimal fiber angles and layer group thicknesses of the laminated composite plates for attaining maximum stiffness and simultaneously satisfying the imposed side constraints. The feasibility of the proposed constrained multi-start global optimization algorithm is validated by means of a simple but representative example and its applications are demonstrated by means of a number of examples on the maximum stiffness design of symmetrically laminated composite plates. The effects of length-to-thickness ratio, aspect ratio, and number of layer groups upon the optimum fiber angles and layer group thicknesses of the plates are investigated.
OPTIMAL PARAMERERS FOR CURING GRAPHITE-EPOXY COMPOSITE LAMINATES
(1995-01-15)
KAM, TY
;
LAI, FM
;
SHER, HF
;
交大名義發表
;
機械工程學系
The optimal curing parameters of a cure cycle for achieving maximum mechanical properties of Gr/ep composite laminates are determined via a multi-level optimization approach. Laminated composite specimens cured under various pressures, temperatures and times are tested with an Instron testing machine. Test results: are then used in the proposed multi-level optimization method to determine the optimal curing parameters. The effects of the curing parameters on the mechanical properties of the laminates are studied and discussed It was found that a cure cycle with two pressure-temperature-time steps can yield composite laminates with comparatively good material properties.