更新单数值分解用于缓慢变化的非静止振动结构的模态分析
Thi-Thuyet Bui1, Viet-Hung Vu2, Zhaoheng Liu1
1École de technologie supérieure, Montréal, QC, Canada.
概括
这项研究引入了一种新方法,用于分析随时间缓慢变化的结构中的振动. 它使用短时间的滑动窗口和先进的数学技术来准确地跟踪非静止振动期间的模态参数.
科学领域:
- 结构动力学 结构动力学
- 振动分析 振动分析
- 系统识别系统识别系统
背景情况:
- 模式分析对于理解结构性行为至关重要.
- 传统的方法与非静止和缓慢变化的振动系统作斗争.
- 准确识别模式参数对于结构性健康监测至关重要.
研究的目的:
- 为缓慢变化的振动结构进行模态分析提出一种新的方法.
- 解决动态系统中非静止振动的挑战.
- 为了准确地监测模式参数,实时对不断变化的结构进行监测.
主要方法:
- 矢量自回归 (VAR) 模型用于系统识别.
- 使用短时间滑动窗口 (STSW) 方法来捕捉短暂的行为.
- 递归最小平方估计和奇点值分解 (SVD) 用于参数估计.
主要成果:
- 拟议的方法有效地确定缓慢变化的系统的模式参数.
- 该技术在处理非静止振动数据方面表现出强度.
- 通过数值模拟和在液压轮机叶片上的实验测试来验证.
结论:
- 基于STSW的新型VAR方法为缓慢变化的结构的模态分析提供了有效的解决方案.
- 这种方法提高了监控具有变化特征的动态系统的能力.
- 这些发现对结构健康监测和工程应用有影响.
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