弹性模式NRUS:理论
1Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
Ultrasonics
|May 7, 2025
概括
这项研究使用非线性共振超声波谱学 (NRUS) 分析了细光束中的柔性振动. 它解释了材料歇斯底里如何导致非线性频率转移和减,这对于损坏检测至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 固体力学 固体力学是什么
- 非线性动力学是一种非线性动力学.
背景情况:
- 非线性共振超声谱 (NRUS) 是检测材料亚结构损伤和表征应变依赖性质的关键.
- 虽然纵向共振是常见的,但在NRUS应用中越来越多地探索曲和扭曲模式.
研究的目的:
- 以非线性歇斯底里斯形式分析薄型光束的曲振动,作为曲NRUS实验的模型.
- 为了解释在共振频率转移和阻尼能力中观察到的依赖应变的非线性行为.
主要方法:
- 采用戴维登科夫歇斯底里功能来模拟曲振动中的歇斯底里运动.
- 结合经典的非线性来推导共振频率转移和减的一般公式.
- 导出准静态的脊柱曲线来澄清依赖应变的行为.
主要成果:
- 戴维登科夫函数解释了非线性共振频率与应变的变化.
- 一般公式允许从共振频率转移和阻尼中实验确定hysteresis参数.
- 经典的非线性参数 (正方形和立方形) 可以通过NRUS提取.
结论:
- 柔性NRUS实验可以量化材料非线性歇斯底里.
- 将传感器信号精确校准到物理量 (应变/加速度) 是绝对歇斯底里参数确定必不可少的.
- 了解非线性信号行为对于可靠的材料表征至关重要.
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