优化地面热交换器的填充材料:对回收混凝土聚合物和飞灰进行研究,以提高热导率
1Institute of Civil Engineering, Warsaw University of Life Sciences-SGGW, 166 Nowoursynowska Str., 02787 Warsaw, Poland.
Materials (Basel, Switzerland)
|December 17, 2024
概括
回收混凝土聚合物和飞灰混合物显示,地面热交换器的热导率得到了改善. 这种混合物提高了热交换效率,特别是在潮湿时,提供了可持续的回填解决方案.
科学领域:
- 地质技术工程 地质技术工程
- 可持续材料科学科学 可持续材料科学
- 可再生能源系统可再生能源系统
背景情况:
- 浅垂直地面热交换器 (GHEs) 需要高效的回填材料.
- 回收混凝土聚合物 (RCA) 和飞灰 (FA) 是潜在的可持续替代品.
- 优化它们的热性能属性对于GHE效率至关重要.
研究的目的:
- 评估RCA,FA及其混合物 (RCA+FA) 作为GHEs的回填材料.
- 为了确定最佳的混合比和压缩特性.
- 在不同的湿度条件下评估这些材料的导热性.
主要方法:
- 进行了粒度测量,空气测量和Proctor压缩测试.
- 使用TP08探头测量了导热率.
- 伍兹赛德和梅斯默模型和Kersten数被用于导热率建模.
主要成果:
- 在较低的湿度下,RCA 压缩得很好; FA 需要更高的湿度.
- 10%的FA添加优化了RCA空隙填充.
- RCA+FA混合物显示热导率明显高于单个组件,特别是在和附近.
- 建模证实了高导电性和对湿度水平的准确预测.
结论:
- 该RCA+FA混合物是一个有前途的,高性能回填材料为GHEs.
- 最佳的水分含量通过水桥梁显著提高了导热率.
- 这种可持续材料为地热系统提供了更好的热交换效率.
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