Pollutant dispersion characteristics under hybrid natural ventilation with mechanical exhaust in industrial buildings: Effect of initial source release settings

• The pollutant dispersion mechanism was experimentally and numerically investigated. • The hybrid ventilation mode was designed and analyzed under multi-sources releases. • The initial pollutant releases cause obvious effects on H 2 S diffusion performance. • High indoor temperatures are beneficial for reducing the pollutant concentration. Poor ventilation usually leads to the inability to timely eliminate many toxic and harmful gases in industrial buildings, which has a negative impact on the health of occupant workers. Ventilation not only improves working environment, but also increases personnel work efficiency, which is of great significance for creating a productive environment in industrial buildings. Although researchers have conducted a large amount of investigations on ventilation in industrial plants, there is a paucity of studies on the effect of the initial source release condition on pollutant dispersion performance. In this study, the dispersion characteristics of harmful gas hydrogen sulfide H 2 S, typical in industrial plants, were numerically simulated under hybrid induced ventilation with mechanical exhaust. A scaled model test was designed and carried out using working medium sulfur hexafluoride SF 6 , and the test data was utilized to validate the numerical model. The influence of the initial settings of pollutant release sources, including the temperature of release source, opening ratio of release source and the intermittent release of pollutant source on H 2 S dispersion, velocity and temperature distribution, and concentration distribution was analyzed. The pollutant removal efficiency was adopted to evaluate the ventilation performance. Some valuable findings were obtained. This study is significant to further understand the dispersion mechanism of H 2 S in rubber processing workshops and can supply a technique reference for the ventilation system design in associated industrial buildings.