Qi Xuejun, Lin Shuang, Tao Shuyan, Patchigolla Kumar
School of Architecture and Civil Engineering, Xihua University, Chengdu, China.
School of Water, Energy & Environment, Cranfield University, Cranfield, UK.
Sci Rep. 2022 Sep 7;12(1):15144. doi: 10.1038/s41598-022-19482-0.
With the improvement of people's living standards, they have higher requirements for indoor thermal comfort in the cold season. Solar wall utilizing solar energy for heating can reduce carbon emissions and achieve carbon neutrality. In the aspect of solar wall research, the influence of wall structure on the thermal performance of double-channel porous solar wall is limitedly investigated. In fact, the optimization design of wall structure is important for the thermal performance of solar wall and its applications. Therefore, a simplified three dimensional room model is built to study the influence of the wall structure on the thermal performance of porous solar wall by numerical simulation. With this model, different channel spacing and thickness of porous walls were used to determine the optimal design for a double-channel porous solar wall in terms of enhancing the heat storage. Moreover, the influence of the surface emissivity on the characteristics of heating and temperature field of double-channel porous solar wall are studied based on the optimal structure. The CFD simulation results indicate that the optimal structure parameters should include spacing of 0.08 m for channel 1, the porous wall thickness should be 0.08 m, and the air channel 2 spacing should be 0.06 m. The temperature of air channel 1 and air channel 2, the indoor temperature, and the heat storage of porous wall decrease with the increase of the surface emissivity of the porous wall. In order to improve the heat storage performance of double-channel porous solar wall, the outer surface of the porous wall should use a lower emissivity material. The outer surface emissivity of porous wall has a significant impact on the heat storage of the porous wall and little effect on the thermal storage wall. The temperature of porous wall is always higher than that of outdoor environment temperature.
随着人们生活水平的提高，他们在寒冷季节对室内热舒适性有了更高的要求。利用太阳能供暖的太阳能墙可以减少碳排放并实现碳中和。在太阳能墙的研究方面，墙体结构对双通道多孔太阳能墙热性能的影响研究较少。实际上，墙体结构的优化设计对于太阳能墙的热性能及其应用至关重要。因此，建立了一个简化的三维房间模型，通过数值模拟研究墙体结构对多孔太阳能墙热性能的影响。利用该模型，采用不同的通道间距和多孔墙厚度，以确定双通道多孔太阳能墙在增强蓄热方面的最佳设计。此外，基于优化结构研究了表面发射率对双通道多孔太阳能墙加热特性和温度场的影响。计算流体动力学（CFD）模拟结果表明，最佳结构参数应包括通道1间距为0.08 m，多孔墙厚度应为0.08 m，空气通道2间距应为0.06 m。随着多孔墙表面发射率的增加，通道1和通道2的空气温度、室内温度以及多孔墙的蓄热均降低。为了提高双通道多孔太阳能墙的蓄热性能，多孔墙的外表面应使用发射率较低的材料。多孔墙外表面发射率对多孔墙的蓄热有显著影响，而对蓄热墙的影响较小。多孔墙的温度始终高于室外环境温度。
