Effect of particle sizes on the particle restraint and removal efficiencies in a laboratory utilizing a lagrangian particle-tracking method

The effect of the different particle sizes on the efficiency of restraining particles from entering the laboratory and the efficiency of particle removal from the laboratory were investigated by simulating the flow conditions, accompanied by a Lagrangian particle-tracking method to calculate the trajectories of the particles in the laboratory. The cases containing particles with different particle size ranging from 10 to 30 um and the case without gravity effect were used to investigate the restraint and removal effects in the study. The results indicate that the restraint rate decreases by the particle size enlarged and the restraint rate of particles is the best under without gravity condition. However, the removal rate increases by the particle size enlarged and the removal rate of particles is the worst under without gravity condition. It is also found that for the case with the particle size smaller than 10 um, the gravitational effect is much smaller and can be neglected. Therefore, for the case with the size of the contaminant smaller than 10 um, the distribution of pollution in an indoor space can be obtained by solving the gaseous concentration equation to simulate the dispersion and deposition of pollutant particles inside an indoor space. With the Lagrangian Particle-Tracking Method, the trajectories of micro-particles can be traced and calculated the in time and the gravity effect can also be considered in the analysis. By tracing and calculating the trajectories of micro-particles in time, the particle restraint and removal effects can be explicitly indicated by calculating the amount of particles that enter or leave the laboratory.