Analysis of thermal comfort during movement in a semi-open transition space

Abstract

Urbanization has increasingly drawn attention to outdoor thermal comfort. The most common strategy to avoid direct sunlight is to apply overhead layer eaves. The spaces under the overhead layer are commonly called transition spaces. Experimental studies were completed in a transition space at Guangzhou University to study transient thermal comfort when moving outdoors. At every phase of the experiment, subjects walked for 20 min at different speed levels and then took a 10-min rest. The subjective thermal responses and physical indices were recorded, using the thermal environment parameters measured in the transition space. In addition, to develop a predictive thermal comfort model, the effects of variations in metabolic rates caused by body movement, the relationships between the mean thermal sensation vote (MTSV) and thermal indices, including physiologically equivalent temperature (PET) and universal thermal climate index (UTCI), were analyzed. An improved predictive model accurately predicted thermal comfort, regardless of dynamic walking or static processes. Further, the effect of turbulence intensity on the convective heat transfer of the human body was found to be underestimated, which caused an overestimation of the thermal storage in the human body by approximately 20%.