A simple approach to reduce the governing equations for orthotropic corrugated core sandwich plates to a single equation containing only one displacement function is presented, and the exact solution of the natural fr...A simple approach to reduce the governing equations for orthotropic corrugated core sandwich plates to a single equation containing only one displacement function is presented, and the exact solution of the natural frequencies for rectangular corrugated-core sandwich plates with all edges simply-supported is obtained. Furthermore, two special cases of practical interests are discussed in details.展开更多
Truss-core sandwich plates have received much attention in virtue of the high values of strength-to-weight and stiffness-to-weight as well as the great ability of impulseresistance recently. It is necessary to study t...Truss-core sandwich plates have received much attention in virtue of the high values of strength-to-weight and stiffness-to-weight as well as the great ability of impulseresistance recently. It is necessary to study the stability of sandwich panels under the influence of the thermal load. However, the sandwich plates are such complex threedimensional （3D） systems that direct analytical solutions do not exist, and the finite element method （FEM） cannot represent the relationship between structural parameters and mechanical properties well. In this paper, an equivalent homogeneous continuous plate is ideMized by obtaining the effective bending and transverse shear stiffness based on the characteristics of periodically distributed unit cells. The first order shear deformation theory for plates is used to derive the stability equation. The buckling temperature of a simply supported sandwich plate is given and verified by the FEM. The effect of related parameters on mechanical properties is investigated. The geometric parameters of the unit cell are optimized to attain the maximum buckling temperature. It is shown that the optimized sandwich plate can improve the resistance to thermal buckling significantly.展开更多
利用VCM法(volume current method)分析了矩形芯倾斜光纤光栅的辐射场特性.数值仿真了辐射场的二维空间分布,分析了矩形芯倾斜光纤光栅对不同偏振输入光的偏振敏感性.仿真结果表明,矩形芯倾斜光纤光栅对y偏振光的辐射效率比x偏振光的高...利用VCM法(volume current method)分析了矩形芯倾斜光纤光栅的辐射场特性.数值仿真了辐射场的二维空间分布,分析了矩形芯倾斜光纤光栅对不同偏振输入光的偏振敏感性.仿真结果表明,矩形芯倾斜光纤光栅对y偏振光的辐射效率比x偏振光的高;光栅的倾斜角越小,对不同偏振输入光的偏振敏感性也越小.X偏振光和Y偏振光的峰值辐射功率差在光栅倾角为3°时为1.8%,当光栅倾角增大到15°时达到16%.而在倾斜角小于7°的情况下,X和Y偏振光的辐射功率峰值差小于5%.展开更多
文摘A simple approach to reduce the governing equations for orthotropic corrugated core sandwich plates to a single equation containing only one displacement function is presented, and the exact solution of the natural frequencies for rectangular corrugated-core sandwich plates with all edges simply-supported is obtained. Furthermore, two special cases of practical interests are discussed in details.
基金Project supported by the National Natural Science Foundation of China(No.91116008)
文摘Truss-core sandwich plates have received much attention in virtue of the high values of strength-to-weight and stiffness-to-weight as well as the great ability of impulseresistance recently. It is necessary to study the stability of sandwich panels under the influence of the thermal load. However, the sandwich plates are such complex threedimensional （3D） systems that direct analytical solutions do not exist, and the finite element method （FEM） cannot represent the relationship between structural parameters and mechanical properties well. In this paper, an equivalent homogeneous continuous plate is ideMized by obtaining the effective bending and transverse shear stiffness based on the characteristics of periodically distributed unit cells. The first order shear deformation theory for plates is used to derive the stability equation. The buckling temperature of a simply supported sandwich plate is given and verified by the FEM. The effect of related parameters on mechanical properties is investigated. The geometric parameters of the unit cell are optimized to attain the maximum buckling temperature. It is shown that the optimized sandwich plate can improve the resistance to thermal buckling significantly.
文摘利用VCM法(volume current method)分析了矩形芯倾斜光纤光栅的辐射场特性.数值仿真了辐射场的二维空间分布,分析了矩形芯倾斜光纤光栅对不同偏振输入光的偏振敏感性.仿真结果表明,矩形芯倾斜光纤光栅对y偏振光的辐射效率比x偏振光的高;光栅的倾斜角越小,对不同偏振输入光的偏振敏感性也越小.X偏振光和Y偏振光的峰值辐射功率差在光栅倾角为3°时为1.8%,当光栅倾角增大到15°时达到16%.而在倾斜角小于7°的情况下,X和Y偏振光的辐射功率峰值差小于5%.
