一种随机动力学方法,用于根据几种合金材料的温度/频率而变化时间的阻尼
Wenjun Huang1, Guorui Yu1, Wentao Xu2
1AVIC China Helicopter Design and Research Institute, Jingdezhen 333001, China.
Materials (Basel, Switzerland)
|March 13, 2024
概括
精确分析航空航天材料中可变缓的情况至关重要. 这项研究引入了一种新的随机动力学方法,用于更准确地预测结构反应,特别是在高温环境中.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 航空航天工程 航空航天工程
背景情况:
- 在航空航天和先进制造业中,准确的响应分析至关重要.
- 材料的机械参数随服务环境而有很大变化.
- 了解阻尼变化对于结构动态反应至关重要.
研究的目的:
- 为了研究304合金,Sa564高强度合金,GW63K合金和Q235钢的阻尼变化特性.
- 在随机动力学中开发温度/频率依赖的缓冲参数的数值方法.
- 提出一种高效的随机动力学方法,用于分析具有变量减压的结构反应.
主要方法:
- 使用动态机械分析 (DMA) 进行缓冲测试,以揭示可变的缓冲比率.
- 开发一个数值构成关系的温度依赖的缓冲.
- 基于伪激发方法 (PEM) 和变量缓解理论的高效随机动力学方法的推导.
主要成果:
- 在测试的合金和钢中发现了可变的阻尼比率.
- 提出并验证了一种用于对可变减压材料的随机动态响应分析的新型数值方法.
- 与恒定减压模型相比,提出的方法显示出更高的准确性,特别是对于GW63K合金.
结论:
- 开发的随机动力学方法准确地预测了具有可变减压材料的结构的动态反应.
- 恒定缓冲模型与实验结果之间存在显著差异,突出显示了变量缓冲分析的必要性.
- 这些发现特别适用于航空,航空航天和高温应用,其中缓冲变化明显.
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