Experimental study on the robustness of ventilation systems in the control of walking-induced disturbances under different walking modes and temperatures

Abstract

Ventilation system’s effectiveness can be affected by walking-induced disturbances. A series of experiments were performed in a chamber in this study (6.0 m × 5.9 m × 2.5 m) to measure the walking-induced temperature/flow/pollution field fluctuation characteristics. A method for quantifying the robustness of a ventilation system in the control of walking-induced fluctuations was used in this study. The experimental results showed that the cumulative particle exposure levels under walking modes W1, W2 and W3 were 2.04 ± 0.27, 1.72 ± 0.26 and 0.87 ± 0.12 times the exposure levels without human walking. The four ventilation systems all performed well in indoor temperature disturbance control; however, different walking modes and ventilation systems would result in different walking-induced disturbances of the flow and pollutant fields. For the flow field, the highest range scale robustness value was achieved by the side supply and side return (SS) system. For the pollutant field, the range scale robustness value of the SS system was still the highest, 18.7% larger than the lowest value. With the increase in temperature from 18 °C to 28 °C , the range and time scale robustness of the different ventilation systems decreased by 7.7–18.4% and 1.3–15.7%, respectively.