Air distribution of oxygen supply through guardrail slot diffusers in high -altitude hypoxic areas

Oxygen supply is necessary for high-altitude hypoxic areas, especially public spaces with high occupant densities. Traditional oxygen supply systems, including individual oxygen supplies (IOS), distributed centralized oxygen supplies (DCOS) and diffusion-type oxygen supplies (DTOS), are limited in completing oxygen delivery tasks by the balance between low cost and high efficiency. This study elaborated a method for air distribution by adopting guardrail slot diffusers (GSDs) for oxygen-rich air delivery directly to the human breathing zone without changing the basic layouts of high and large spaces. The dynamic breathing zone was obtained by monitoring the swing of people waiting beside a guardrail. Two indicators, the target value of oxygen concentration and the oxygen supply efficiency, were introduced to facilitate the evaluation of oxygen supply through GSDs. Compared with oxygen supply through other existing air distribution systems in high and large spaces, the optimized GSDs have a 9%–27% higher effectiveness, as expressed in terms of the target value of oxygen concentration. The oxygen supply efficiency is 271%–658% higher. The implementation of the system was studied at altitudes of 2000 m, 3000 m, 4000 m and 5000 m, which proved that this oxygen supply system has better implementation effects. By increasing the height of the guardrail by 100 mm, the GSDs can meet the oxygen demand for air inhaled by European and North American adults. The results indicate that this method realized efficient oxygen supply in high-altitude hypoxic areas while reducing oxygen consumption and investment costs. © 2020 Elsevier Ltd