Experimental study on the building evaporative cooling by using the Climatic Wind Tunnel

• Climate Wind Tunnel was used to analyze dynamic evaporating and heat transfer process.
• Using additional thermal resistance to quantify evaporative cooling performance.
• Penman–Monteith model was introduced to analyze hourly evaporation amount.
• Evaporative cooling could consume about 70% of maximum incident solar radiation heat.

Building evaporative cooling is an effective energy saving technology. With the aim to provide a reliable experimental method for the building evaporative cooling research, the dynamic evaporating and heat transfer process of two samples were studied by using the Climatic Wind Tunnel (CWT). The results of this study indicate the following: (1) The thermal resistance of the wet sample was two times that of the dry sample, which significantly improved the thermal insulation capacity of the wet sample. (2) The Penman–Monteith (P–M) model in Pedology was introduced to analyze the evaporation amount which was caused by the comprehensive effect of radiation term and aerodynamic term. The results displayed that the evaporation amount caused by radiation term accounted for 80.4% of the total evaporation amount. (3) The hourly evaporation data were used to calculate the heat balance equation on the facing layer of the wet sample. The calculation results demonstrated that the evaporating process can consume approximately 70% of the maximum incident solar radiation heat.