This article introduces a solar building envelope that integrates salt hydrate-based sorption thermochemical energy storage and photocatalysis to provide a dual functionality of space heating and formaldehyde degradation. The system’s heat output and air purification effectiveness under dynamic exterior conditions are numerically investigated based on the developed multi-physics coupling model. Numerical results reveal that during the charging phase, both the outlet air temperature and the formaldehyde degradation rate initially rise and then decline, peaking at a temperature of 45.1 °C at about 14:30. The clean air delivery rate and degradation rate achieved are 25.5 m/h, and 7.3425 μg/s, with a total energy efficiency of 72.9 %. The discharging phase commences at 19:40, elevating the outlet air temperature from 30 °C to approximately 38.4 °C, and the discharging period extends for over 10 h. The average temperature lift of air and heating power of the storage wall are 17 °C and 19.1 kW/m, respectively. Moreover, the influence of various factors such as solar radiation intensity and relative humidity on the system’s performance are systematically investigated. The findings of this study may contribute valuable insights into the advancement of efficient solar building envelopes.

中文翻译：

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吸附储热-光催化组合太阳能外壳的空间加热和甲醛降解行为预测


本文介绍了一种太阳能建筑围护结构，它集成了基于盐水合物的吸附热化学储能和光催化，以提供空间加热和甲醛降解的双重功能。基于开发的多物理耦合模型，对动态外部条件下系统的热输出和空气净化效果进行了数值研究。数值结果表明，在充电阶段，出风温度和甲醛降解率均先上升后下降，在14:30左右达到峰值45.1 ℃。达到的清洁空气输送量和降解率分别为25.5 m/h和7.3425 μg/s，总能源效率为72.9%。 19时40分开始放电阶段，出口空气温度从30℃升至约38.4℃，放电时间持续10多小时。空气平均温升为17℃，库墙平均加热功率为19.1kW/m。此外，系统地研究了太阳辐射强度和相对湿度等各种因素对系统性能的影响。这项研究的结果可能为高效太阳能建筑围护结构的进步提供有价值的见解。