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在结构低调共振下对高速列车轴箱连接螺栓的多轴疲劳分析
Yaqin Feng1, Fansong Li1, Kang Shu2
1State Key Laboratory of Rail Transit Vehicle System, Southwest Jiaotong University, Chengdu 610031, China.
Sensors (Basel, Switzerland)
|September 28, 2023
概括
高速列车轴箱前盖在亚波共振风险螺栓故障. 消除轮多角化显著提高了螺栓疲劳寿命,防止了多轴疲劳故障.
科学领域:
- 机械工程 机械工程
- 振动分析 振动分析
- 疲劳分析 疲劳分析
背景情况:
- 高速列车轴箱前盖中的亚声波共振可能导致螺栓故障.
- 现有的预防方法通常对这种特定的故障模式无效.
研究的目的:
- 在亚声波共振下分析轴箱前盖的动态特征.
- 在这种情况下模拟和预测螺栓的疲劳寿命.
- 找出有效的方法来改善螺栓疲劳寿命.
主要方法:
- 开发并验证了用于动态螺栓应力模拟的线性频率响应分析方法.
- 使用八面体剪切应力标准来确定等效应力振幅.
- 使用S-N曲线来预测疲劳寿命.
主要成果:
- 线性方法准确地模拟了在亚波共振下动态螺栓应力.
- 横向和拉力共振应力都会导致螺栓故障.
- 螺栓在26.8小时的共振后容易发生多轴疲劳失败.
结论:
- 线性应力模拟方法在工程应用中具有实际意义.
- 通过缩短重塑间隔来减少车轮多角化,大大改善了螺栓疲劳寿命.
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