Hydronic radiant floor systems enhanced with phase change materials (PCMs) could achieve significant energy savings while improving the thermal comfort of occupants in lightweight buildings. However, successful integration of PCMs typically requires comprehensive numerical analysis due to their complex nature. This study aims to investigate two scenarios for optimal integration of PCM into the hydronic floor heating system of a highly glazed study room exposed to cold weather conditions. Scenario 1 includes optimization of two design variables, including PCM melting temperature and thickness. Scenario 2 encompasses optimization of seven design variables, including PCM melting temperature and thickness, insulation thickness and thermal conductivity, floor thickness, thermal conductivity, and solar absorbance. Both scenarios are optimized for the six supply water temperatures, ranging from 35.6 °C to 45.6 °C with a 2 °C step. The overall findings suggest that successful integration of PCMs into the hydronic heating system requires a comprehensive solution tailored for the specific application. Thus, scenario 1 and scenario 2 achieved the highest total energy savings of approximately 17.7% and 20.5% for the lowest supply water temperature of 35.6 °C, whereas under both scenarios the supply water temperature of 43.6 °C provided the best thermal comfort. Furthermore, scenario 1 achieved more substantial cooling energy savings over the wider temperature range (41.6-35.6 °C) compared to scenario 2 (39.6-35.6 °C). The findings also suggest that the addition of the insulation layer in the second scenario reduced the thickness of PCM and payback period for more than 70% compared to the first scenario.

中文翻译：

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寒冷气候下高玻璃书房的PCM增强辐射地板的多变量优化

相变材料（PCM）增强的水力辐射地板系统可以节省大量能源，同时改善轻型建筑中居住者的热舒适性。但是，由于PCM的复杂性，成功地集成PCM通常需要进行全面的数值分析。这项研究旨在研究将PCM最佳地集成到暴露于寒冷天气条件下的高玻璃书房的水力地板加热系统中的两种方案。方案1包括两个设计变量的优化，包括PCM熔化温度和厚度。方案2包含七个设计变量的优化，包括PCM熔化温度和厚度，绝缘厚度和导热率，地板厚度，导热率和太阳吸收率。两种方案都针对六个供水温度进行了优化，步进范围为2°C，范围从35.6°C到45.6°C。总体发现表明，PCM成功集成到水力加热系统中需要针对特定​​应用量身定制的全面解决方案。因此，方案1和方案2在最低供水温度35.6°C时实现了最高的总节能量，分别约为17.7％和20.5％，而在两种方案中，供水温度43.6°C都提供了最佳的热舒适性。此外，与方案2（39.6-35.6°C）相比，方案1在更宽的温度范围（41.6-35.6°C）上实现了更多的冷却能源节省。