模拟和分析聚乙烯及其管道的加载,放松和恢复行为
1Department of Mechanical Engineering, University of Alberta, 10-203 Donadeo Innovation Centre for Engineering, 9211-116 Street NW, Edmonton, AB T6G 1H9, Canada.
Polymers
|November 27, 2024
概括
这项研究通过提高参数独特性来增强聚合物的弹-仪表盘模型. 这可以更好地描述聚乙烯的特性.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
背景情况:
- 弹-仪表盘模型被广泛用于聚合物机械行为模拟.
- 一个关键的限制是非唯一的参数值,阻碍了微观结构的相关性.
- 现有的模型很难将变形与微观结构变化独特地联系起来.
研究的目的:
- 为了提高聚乙烯弹端模型参数的独特性.
- 为了在变形和微观结构变化之间建立一个更清晰的关系.
- 为了验证增强模型预测机械行为的能力.
主要方法:
- 开发了一种新的方法,使用压力数据在加载,放松和恢复聚乙烯的过程中.
- 确定了1000组模型参数,适应0.08MPa差距内的放松数据.
- 分析了参数分布,专注于σv,L0.0.的独特行为.
- 选择了五个参数集,差异低于0.04 MPa,用于一致性分析.
主要成果:
- 尽管配合有小差异,但1000个参数集显示了很大的差异.
- 模型参数 σv,L0 呈现出非随机的双路分布.
- 选择的参数集显示出高的一致性,特征放松时间作为一个小例外.
- 该方法成功确定了四个聚乙烯管道的准静态应力,显示了密切的一致性.
结论:
- 可以显著提高聚乙烯弹-仪表盘模型参数的独特性.
- 这种增强的参数独特性可以更好地描述机械行为的特征.
- 这种精细的模型有助于进一步研究聚乙烯在变形过程中的微结构变化.
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