基于Lamb波的时间频率特征的新应力测量策略
Hexin Cui1, Zhichun Zhang2, Hongbo Jia3
1Department of Astronautical Science and Mechanics, Harbin Institute of Technology (HIT), P.O. Box 301, No. 92 West Dazhi Street, Harbin 150001, People's Republic of China.
Ultrasonics
|July 14, 2024
概括
这项研究引入了一种使用Lamb波来测量压力的新方法,专注于时间频率特征而不是传统方法. 该方法在材料应力评估方面显示出有希望的稳定性和准确性.
科学领域:
- 材料科学 材料科学 材料科学
- 非破坏性测试 不破坏性测试
- 声波传播的声波传播
背景情况:
- 传统的Lamb波压力评估依赖于飞行时间 (TOF) 或速度,这可能对应力变化不敏感.
- 关于利用时间频谱特征用于压力评估的研究有限.
- 开发更敏感的应力测量技术对于结构健康监测至关重要.
研究的目的:
- 提出并验证使用Lamb波的新型单轴应力测量方法.
- 调查时间频谱分布 (TFSD) 斜率和脉冲宽度影响因子对应力传感的有效性.
- 分析激发信号参数和噪声对这些新型应力敏感特征的影响.
主要方法:
- TFSD斜率表达式的理论导出.
- 有限元模拟用于验证理论预测.
- 在单轴拉伸负荷下使用板样本进行实验验证.
- 基于衍生应力表达式的测量稳定性和精度的分析.
主要成果:
- 有限元模拟结果与TFSD斜率的理论预测保持一致.
- 实验测试证实了拟议方法的可行性.
- 脉冲宽度冲击因子方法显示出极好的测量稳定性,最大应力标准偏差为3.76 MPa.
- 通过TFSD斜率方法,实现了最大应力标准偏差为9.12 MPa.
结论:
- 拟议的时间频率特征为基于Lamb波的应力测量提供了一个有希望的替代方案.
- 脉冲宽度冲击因子在实验条件下表现出高于TFSD斜率的稳定性.
- 进一步的研究可以优化这些方法,以提高压力评估的准确性和灵敏度.
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