弹性体纤维的双热量建模和实验验证验
Guangkai Mei1, Jiatian Li1, Danyang Feng1
1State Key Laboratory of Medicinal Chemical Biology, College of Chemistry and College of Pharmacy, Key Laboratory of Functional Polymer Materials, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin, 300071, China.
Macromolecular rapid communications
|June 21, 2023
概括
一个新的twistocaloric模型解释了纤维中的扭转制冷. 这种固态冷却技术显示出高效率和低体积变化,实验结果验证了理论预测.
科学领域:
- 固态物理 固态物理
- 材料科学是一种材料科学.
- 热力学是一种热力学.
背景情况:
- 由扭力应力引起的变化驱动的双热效应,使纤维能够有效地冷却固态.
- 目前理论模型和数学框架的局限性阻碍了双热制冷的广泛应用.
研究的目的:
- 为了开发一个理论模型的双热效应.
- 为了确定自然纤维和热塑性弹性线的扭曲密度和温度变化之间的关系.
- 为了实验验证开发的双卡路里模型.
主要方法:
- 开发了一个扭曲热量模型,将扭曲密度与温度变化相关联.
- 使用扭矩执行器,扭矩传感器和温度测量系统构建一个实验装置.
- 使用马克斯韦关系在剪切应变下测量双卡路里系数.
主要成果:
- 该研究成功地建立了天然纤维和热塑性弹性体线中双热效应的模型.
- 实验验证证了模型关于扭曲密度和温度变化之间的关系的预测.
- 双热系数被准确测量,证明了理论和实验发现之间的一致性.
结论:
- 开发的twistocaloric模型准确地捕捉了纤维材料中扭曲应力引起的温度变化.
- 实验性表征支持理论预测,为扭曲制冷的更广泛应用铺平了道路.
- 这项工作为推进基于双热效应的固态冷却技术提供了基础的理解.
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