表面应力驱动模型的应用,用于高振动模式的功能等级的梁
Giuseppe Lovisi1, Luciano Feo1, Annavirginia Lambiase1
1Department of Civil Engineering, University of Salerno, 84084 Fisciano, Italy.
Nanomaterials (Basel, Switzerland)
|February 23, 2024
概括
这项研究揭示了表面能量和远程相互作用如何影响纳米光束振动. 考虑到这些表面效应对于理解功能分级纳米束的动态反应至关重要.
科学领域:
- 机械工程 机械工程
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
背景情况:
- 表面效应显著影响纳米结构的机械行为.
- 功能分级材料 (FGM) 为高级应用提供可调节的性能.
- 纳米光束中较高的振动模式对于动态性能至关重要.
研究的目的:
- 研究表面能量和非局部相互作用对FGM纳米光束更高振动模式的综合影响.
- 开发一个全面的非局部弹性模型,包括表面效应.
- 分析各种参数对纳米光束动态的影响.
主要方法:
- 利用表面应力驱动的非局部理论.
- 通过汉密尔顿的原理推导出管理方程.
- 对非局部参数和材料梯度指数进行了参数研究.
主要成果:
- 表面效应在纳米光束的动态反应中起着核心作用.
- 确定了第二到第五种模式的规范化非局部自然频率.
- 这项研究分析了四个静态方案:Cantilever,Simply-Supported,Clamped-Pinned和Clamped-Clamped. 这四个静态方案包括:Cantilever,Simply-Supported,Clamped-Pinned和Clamped-Clamped.
结论:
- 表面效应对于精确建模纳米光束振动至关重要.
- 动态反应对非局部影响,材料梯度,截面形状和边界条件敏感.
- 这项研究为分析纳米光束动态提供了一个强大的数学框架.
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