Abstract

In this article, frequency analysis of multi-sized hybrid nano-composites (MHC) disk (MHCD) resting on elastic media and located in an environment with gradually changed temperature feature is presented. Carbon fibers (CF) or carbon nanotubes (CNTs) in the macro or nano sizes respectively are responsible for reinforcing the matrix. For prediction of the efficiency of the properties MHCD’s modified Halpin-Tsai theory has been presented. The strain-displacement relation in multi-sized laminated disk’s dynamics through applying third-order-shear-deformation-theory is determined. The energy methods called Hamilton’s principle is applied for deriving the motion equations along with boundary conditions, which has ultimately been solved using generalized differential quadrature method. The deflection as the function of time can be solved by the fourth-order Runge-Kutta numerical method. At the final stage, the outcomes illustrate that patterns of FG, fibers’ various directions, the W_CNT and V_F factors, top surface’s applied temperature have considerable impact on the MHCD’s dynamics. Another important consequence is that MHC structure with FG-A and UD patterns have a similar effect on the dimensionless natural frequency of the GPLRC disk, while FG-X has the lowest stability and natural frequency. A useful suggestion is that increasing the value of the length to thickness ratio of MHC not only decreases the central deflection of the structure through time but also causes to decrease real-time domain changes for the MHC viscoelastic annular plate. Numerical results declare that viscoelastic disks fabricated from the hybrid nanocomposites can endure higher frequencies compared with those consisted of conventional composites.

摘要

本文介绍了多尺寸混合纳米复合材料 (MHC) 圆盘 (MHCD) 的频率分析，该圆盘位于弹性介质上并位于温度逐渐变化的环境中。宏观或纳米尺寸的碳纤维 (CF) 或碳纳米管 (CNT) 分别负责增强基质。为了预测属性的效率，已经提出了 MHCD 修改后的 Halpin-Tsai 理论。应用三阶剪切变形理论确定了多尺寸叠片盘动力学中的应变-位移关系。称为哈密顿原理的能量方法用于推导运动方程以及边界条件，最终使用广义微分求积法求解。作为时间函数的挠度可以通过四阶龙格-库塔数值方法求解。在最后阶段，结果表明 FG 的模式、纤维的各个方向、W _CNT和V _F因素、顶面施加的温度对 MHCD 的动力学有相当大的影响。另一个重要的结果是具有 FG-A 和 UD 模式的 MHC 结构对 GPLRC 盘的无量纲固有频率具有相似的影响，而 FG-X 具有最低的稳定性和固有频率。一个有用的建议是，增加 MHC 的长厚比值不仅会随着时间的推移减少结构的中心挠度，还会导致 MHC 粘弹性环形板的实时域变化减少。数值结果表明，与传统复合材料相比，由混合纳米复合材料制成的粘弹性盘可以承受更高的频率。