Temperature-induced variations in structural dynamic characteristicspart II: analytical
Temperature-induced variations in structural dynamic characteristicspart II: analytical
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温度引起的结构动态特性变化第二部分：分析
DOI：
10.1117/12.248684
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
L. Mitchell
中科院分区：
文献类型：
--
作者：
C. E. Woon;L. Mitchell
近年来，对结构动力特性的精确和详细的了解变得越来越重要。因此，经常用于验证和更新有限元模型的实验数据的准确性变得极其重要。实验表明，环境温度的微小变化会引起轻阻尼结构的固有频率的明显变化，这反过来又可能导致实验和分析结果的显着误差。因此，有必要充分了解所涉及的物理驱动机制，以便实施适当的稳定性控制措施。本文提出了一个分析调查的自然频率的变化所造成的微小的温度变化。建立了考虑温度效应的板动力学模型.温度的变化影响杨氏模量、结构尺寸（通过热膨胀）和边界条件效应。这些变化引起的固有频率的变化，导致显着的变化，在共振频率附近的结构动力响应，特别是当阻尼低。在本研究的有限温度范围内，固有频率随温度的升高而线性下降。灵敏度分析表明，杨氏模量的温度依赖性是影响固有频率变化的主要因素，但边界条件的影响也可能是重要的。
Precise and detailed knowledge of the dynamic characteristics of structures has become increasingly important in recent years. As a consequence, the accuracy of experimental data, which is often used to validate and to update finite element models, has become extremely important. It has been shown experimentally that small changes in ambient temperature can cause distinct variations in the natural frequencies of a lightly damped structure which, in turn, may result in significant errors in experimental and analytical results. Therefore, a good understanding of the physical driving mechanisms involved is necessary so that adequate stability control measures may be implemented. This paper presents an analytical investigation of the variations in natural frequency caused by small changes in temperature. An analytical plate dynamic model is developed accounting for the effects of temperature- dependent material properties. Changes in temperature influence Young's modulus, structural dimensions (via thermal expansion), and boundary condition effects. These change cause variations in the natural frequencies which result in marked changes in structural dynamic response at frequencies near resonance, especially when damping is low. Natural frequencies decrease linearly with increasing temperature over the limited temperature range in this study. A sensitivity analysis indicates that the temperature-dependence of Young's modulus is the dominant factor influencing the variations in natural frequency, but boundary condition effects may also be important.