绿色绝缘纤维介质有效导热的计算模型
Hamidou Sankara1,2, Dominique Baillis1, Ousmane Coulibaly2
1LaMCoS, INSA-Lyon, CNRS UMR 5259, Université de Lyon, 69621 Villeurbanne, France.
Materials (Basel, Switzerland)
|January 11, 2024
概括
本研究提出了一种新的数值模型,用于计算纤维绝缘材料的有效导热率. 一个矩形的代表元素体积和均的温度梯度边界条件提供了更准确的热性质预测.
科学领域:
- 材料科学 材料科学 材料科学
- 热力工程是热力工程中的一个.
- 计算力学 计算力学 计算力学
背景情况:
- 优化绿色绝缘纤维介质的热性能需要对有效的热性能进行准确的建模.
- 现有的分析模型通常依赖于简化的假设,可能忽略了关键的热传递现象.
研究的目的:
- 开发和验证一个强大的数值模型来计算随机定向纤维介质的有效导热率.
- 研究代表性基本体积 (REV) 形状和边界条件对模型准确性的影响.
主要方法:
- 用于数值模拟的有限元法 (FEM).
- 立方体和矩形平行管 (切片) REV 的比较.
- 研究混合和均的温度梯度边界条件.
主要成果:
- 数值模型准确地预测了有效的导热率,与Juncus maritimus纤维介质的实验数据相比,偏差低至7%.
- 具有均温度梯度边界条件的矩形REV切片比具有混合边界条件的立方REV更准确.
- 该模型考虑了短纤维和长纤维情况,解决了分析方法的局限性.
结论:
- 建议使用矩形REV和统一的温度梯度边界条件的拟议数值模型,以准确地估计纤维材料的有效导热率.
- 这种方法提高了新型绿色绝缘材料的热性能优化.
- 该模型的稳定性和准确性与现有文献数据进行了验证.
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