Experimental study of thermal sensation and physiological response during step changes in non-uniform indoor environment

Abstract

To examine thermal comfort and the corresponding physiological responses in non-uniform and dynamic indoor thermal environments,this article presents the investigation of thermal sensations and skin temperatures during step changes between the ambient environment and the workstation where local ventilation devices supplied air motion around the subjects’ heads. Twenty-three labtests with human subjects were conducted to provide summer cooling in a controlled-environment chamber. Overall thermal sensations and skin temperatures were collected and analyzed. Data collected as subjects stepped between the ambient environment and the controlled-environment workstation displayed hysteresis and overshooting. That facial skin temperature correlates with thermal sensation provides a causal explanation of the overshooting and hysteresis. Further, the minimum change on facial skin temperature required to register a just-noticeable difference on thermal sensation was calculated to explore the correlation between facial skintemperature and overall thermal senation. In conclusion, thermal sensation data provide a sound quantifiable foundation for comfortpositive non-uniform indoor thermal environments. Facial skin temperature explains thermal sensation’s changing characteristics during step changes in non-uniform thermal environments under varying local cooling methods.

Quan Jin

Senior researcher

Quan Jin is Senior Researcher in the research group Sustainable Building at the Division of Building Technology, and in the Area of advance Energy. She conducts research on indoor environmental quality from multiple disciplinary perspectives, and their impact on building energy efficiency and occupant health and comfort. The goal is to create tools and knowledge to improve human well-being and productivity in sustainable buildings while minimizing the energy consumption.