论文标题
应力驱动的非局部束的随机振动,外部阻尼
Random vibrations of stress-driven nonlocal beams with external damping
论文作者
论文摘要
通过压力驱动的非局部力学研究了带有外部阻尼的小型Bernoulli-Euler束的随机弯曲振动。考虑到梁与周围环境之间的粘性相互作用,模拟了阻尼效应。负载是通过考虑其随机性质来建模的。这种动态问题的特征是在相关位移场的时间进化的时空和时间进化中的随机部分微分方程。进行差异征曲纳分析以评估模态时间坐标和模式形状,从而提供了响应溶液的完整随机描述。分析检测到功率光谱密度,相关函数,固定和非平稳差异的闭合形式表达式。根据位移的刚度,方差和功率谱密度评估尺寸依赖性动态行为。结果对于设计和优化现代小型设备的结构组件,例如微型和纳米电子机械系统(MEMS和NEMS)可能很有用。
Stochastic flexural vibrations of small-scale Bernoulli-Euler beams with external damping are investigated by stress-driven nonlocal mechanics. Damping effects are simulated considering viscous interactions between beam and surrounding environment. Loadings are modeled by accounting for their random nature. Such a dynamic problem is characterized by a stochastic partial differential equation in space and time governing time-evolution of the relevant displacement field. Differential eigenanalyses are performed to evaluate modal time coordinates and mode shapes, providing a complete stochastic description of response solutions. Closed-form expressions of power spectral density, correlation function, stationary and non-stationary variances of displacement fields are analytically detected. Size-dependent dynamic behaviour is assessed in terms of stiffness, variance and power spectral density of displacements. The outcomes can be useful for design and optimization of structural components of modern small-scale devices, such as Micro- and Nano-Electro-Mechanical-Systems (MEMS and NEMS).