Topography and size optimization of composite structure to control buckling temperature and thermal buckling mode shape

초록

Composite material has been widely used in the engineering field because of its excellent fatigue and corrosion resistance and good impact resistance. However, the structural instability of composite structure is observed due to the thermal buckling phenomena when applied with heat. The present study aims to achieve the thermal structural stability of composite plate structure by developing a topography optimization method and a size optimization method to control linear buckling temperature and thermal buckling modes. In this study, the nodal positions or the shell element thicknesses are set as the design variables. The buckling temperature values and buckling mode shapes are included in the objective function. The developed optimization methods determine the optimal thickness distributions and geometries of composite structure, to induce the target buckling temperatures and target buckling mode shapes. To demonstrate the validity of the present approach, several structural optimization problems considering composite plates are solved. The proposed optimization methods allows the convergence of buckling temperatures within 1% range, and that of buckling mode shapes to desired geometries. In addition, the engineering application of the optimization method on reaction turbine blade is presented. The results of this study support the implementation of the topography and size optimization methods to achieve the optimum structural designs for various engineering applications regarding buckling temperature and thermal buckling mode shape.

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