一种实验方法,在从液体转变为固体的过程中捕获细粒混凝土的导热系数
Yannik Schwarz1, Denis Ratke2, David Sanio1
1Institute of Concrete Structures, Ruhr-Universität Bochum, 44780 Bochum, Germany.
Materials (Basel, Switzerland)
|May 11, 2024
概括
研究人员开发了一种新的实验方法,用于测量混凝土在从液体变固体过渡过程中的导热率. 这项研究揭示了液体混凝土的导热率更高,并且在固化过程中呈指数级下降.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 热力学是一种热力学.
背景情况:
- 固化混凝土的导热率 (λ) 是众所周知的,但关于它从液态过渡到固态的研究有限.
- 现有的混凝土液态和过渡过程模型是简化的和定性化的,缺乏实验验证.
- 需要一种实验方法来准确测量混凝土相变期间的导热率.
研究的目的:
- 设计和评估一种新的实验测试装置,用于测量细粒度混凝土在从液态到固态过渡期间的导热系数 (λ).
- 调查热导率在过渡阶段对水合的依赖性.
- 将实验结果与理论预测进行比较,并利用数字双胞胎进行进一步分析.
主要方法:
- 开发了一台定制的测试装置,使用受控的外部源来加热液体混凝土.
- 通过光纤传感器,沿样本的高度测量了短暂的温度分布.
- 导热率是从测量的热量流和温度梯度在特定的评估长度获得的.
- 测试平台的数字双胞胎被创建以模拟扩展的边界条件并优化实验参数.
主要成果:
- 发现液态的导热率 (λ) 大约是固态的1.4倍.
- 在短暂的液体到固体过渡过程中,导热率呈指数级下降.
- 数字模拟表明,更高的热源温度提高了结果的稳定性.
- 导热率的推导在很大程度上取决于所选择的评估长度.
结论:
- 开发的实验方法和数字双胞胎提供了一个强大的方法来研究混凝土在相位过渡期间的导热性.
- 推用于导热率的推评估长度是最大粒径的三倍.
- 这些发现为改善混凝土在关键过渡阶段的热模型提供了关键数据.
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