Computational fluid dynamics simulation of cigarette smoke particulate phase retained by cigarette filter
A computational fluid dynamics model was developed to simulate the flow and retention of cigarette smoke aerosol particulate phase in an acetate filter whilst using nicotine as a surrogate for the particulate phase of the mainstream smoke. A volume averaging method was applied to simplify the physical model of filter. Commercially available software, ANSYS FLUENT 13.0, was used to simulate the distribution of smoke particulate phase (nicotine) in the cigarette filter at different time points of the puff (puff duration: two seconds, under ISO conditions). At the end of the smoking procedure, the axial and radial distribution of the volume fraction profiles of nicotine in the filter, as well as the filter filtration efficiency, were obtained. To validate the effectiveness of the developed model, the simulation results in this work were compared with experimental data. The results showed that: 1) The axial distribution of the nicotine retention in the cigarette filter calculated by simulation was that the concentration of nicotine decreased gradually from the tobacco column side to the mouth end of the filter, which is in good agreement with the experimental data. 2) In radial direction, both experimental and simulated concentration of nicotine in the cigarette filter exhibited a reducing tendency from the centre to the periphery of the filter, however, the simulated concentration increased near the periphery of the filter. 3) The relative deviation of filter filtration efficiency to nicotine between simulated and experimental results was 21%.