The efficient removal of droplets with different ventilation systems is a key scientific problem affecting an indoor environment. In this study the transport of monodispersed droplets generated from an open tank with a large length/width ratio was investigated under the influence of an upper-receiving ventilation (URV) system and a push-pull ventilation (PPV) system, based on numerical simulation. The movement of droplets under the two systems were compared. The effects of the initial diameters of the droplets and the exhaust airflow velocity on the capture efficiency and removal rate of droplets were evaluated. The results showed that the turbulence dispersion of droplets, gravity acting on the droplets and vortex interaction contributed to the different droplet behaviour under different local ventilation modes and exhaust airflow velocities. The PPV system demonstrated faster droplet removal ability than the URV system, for the same size of droplets. The URV system achieved higher capture efficiency with less energy consumption than the PPV system for droplets with an initial diameter of 10-50 mu m; for those with an initial diameter of 75-100 mu m, the PPV system prevented any droplets from escaping into the occupied zone with less energy cost. The results of this study can contribute to the design and selection of local ventilation modes and the operation conditions required to control droplets. (C) 2019 Elsevier B.V. All rights reserved.