高温应变仪的结构不确定性分析 基于蒙特卡洛随机有限元素方法
Yazhi Zhao1, Fengling Zhang1, Yanting Ai1
1Liaoning Key Laboratory of Advanced Measurement and Test Technology for Aviation Propulsion System, School of Aero-Engine of Shenyang Aerospace University, Shenyang 110136, China.
Sensors (Basel, Switzerland)
|October 28, 2023
概括
高温应变仪显示测量分歧. 本研究使用确定性和随机有限元方法分析系统不确定性,为结果变化提供理论基础.
科学领域:
- 机械工程 机械工程
- 材料科学 材料科学 材料科学
- 传感器技术 传感器技术
背景情况:
- 高温应变仪对于在极端环境中测量应变至关重要.
- 这些仪表的测量结果经常显示出显著的分歧,需要进行不确定性分析.
- 了解这种差异的来源是提高测量精度的关键.
研究的目的:
- 从理论上分析高温应变仪系统的不确定性.
- 为了研究各种参数对延展仪网线的热反应的影响.
- 为解释高温应变仪测量中的分散提供基础.
主要方法:
- 使用MATLAB进行温度场模拟的确定性有限元分析 (FEM).
- 主要子模型方法用于系统建模,包含等效的热和力负载.
- 使用ANSYS进行热机械合分析,以验证MATLAB模拟.
- 随机有限元素方法 (SFEM) 与蒙特卡洛方法 (MCM) 结合用于不确定性量化.
主要成果:
- MATLAB和ANSYS的温度和应变计算显示出最小的差异 (分别为1.34%和0.64%),验证了计算程序.
- 主要子模型方法对应变量表系统FEM有效,显著减少了元素数量.
- 随机分析量化了物理,几何和负载不确定性对电网线的热响应的影响.
结论:
- 开发的计算方法对于高温应变仪分析是准确和有效的.
- 主要子模型方法为张力计系统提供了一种高效的建模策略.
- 这项研究建立了一个理论框架,用于理解和减轻高温应变仪的测量不确定性.
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