Study on heat transfer characteristics of cement-based honeycomb structures based on infrared imaging

Abstract

The honeycomb structure may become the most potential material for constructing low-carbon and energy-saving buildings due to its excellent mechanical and thermal properties. The aim of this study was to investigate the temperature field evolution and heat transfer mechanism of cement-based honeycomb structures (CHSs) based on infrared thermal imaging technology. And the effects of heat source temperature and cavity bulk density on the temperatures of CHS were investigated. The results show that the heat transfer of CHS develops from an unsteady state to a steady state, and its thermal diffusion effect weakens layer by layer upward through the honeycomb cavities. The CHS temperatures increase linearly with increasing heat source temperature, but the temperature increase of the cavity wall is significantly higher than that of the air in the cavity. When the heat source temperatures increase from 40 to 85 °C, the temperature differences between the cavity wall and the air in the cavity increase in the range of 4.67–12.50 °C. The temperatures of the CHSs show a decreasing trend with increasing cavity volumes, and the air temperature reduction in the cavity is about 1.90–2.19 times that of the cavity wall. Moreover, it is found that the cavity wall temperature is mainly controlled by the heat source. In contrast, the air temperature in the cavity is influenced by both the heat source and the cavity volume. Ultimately, we speculate that increasing the thermal resistance of the cavity wall and the cavity volume is beneficial to improve the thermal insulation performance of the CHS.