Climate chamber study on thermal comfort of walking passengers with elevated ambient air velocity

The low ambient air velocity for summer conditions (26 °C, < 0.2 m/s), currently used in Chinese airport terminals, does not meet the thermal comfort demands of passengers. Compared with reducing the ambient temperature by cooling, elevating the ambient air velocity during walking could improve thermal comfort without increasing energy consumption. However, the cooling effect of airflow in ASHRAE Standard 55 and ISO 7730 may not be applicable to the walking status. In this study, 20 male subjects were recruited to simulate summer passengers; they wore clothes with an insulation of 0.57 clo and walked in a climatic chamber at a pace of 1.1–1.2 m/s with a 5 kg bag. During walking, the subjects experienced three operative temperatures (23 °C, 26 °C, and 29 °C) and four ambient air velocity conditions (0.05 m/s, 0.34 m/s, 0.64 m/s, and 0.82 m/s), for a total of 12 combinations. After walking for 15 min, they entered an environment of 26 °C and 0.05 m/s for the sedentary status. The variations in the subjective perception and skin temperature over time were determined. Ambient air velocity settings of 0.64–0.82 m/s compensated for a temperature drop of 3–6 °C for the improvement of thermal comfort. The ‘corrective power’ for 0.34–0.82 m/s was −1 to −5 °C during walking. Thermal acceptability and airflow acceptability were simultaneously considered. A walking comfort zone for summer conditions was identified to guide the environmental design of walking spaces in airport terminals.