Computational fluid dynamic (CFD) simulation of ventilation rate of an unlit cigarette

Abstract

To investigate the influences of different cigarette material parameters on pressure drop, ventilation rate and air velocity distribution within an unlit cigarette, eight cigarettes with different material parameters were simulated by using a Computational Fluid Dynamics (CFD) method with experimental results from the test cigarette materials. The simulated values were compared with the measured values. The results showed that:1) For cigarettes without filter ventilation, about 4% of additional amount of air entered the cigarette through cigarette paper when the air permeability of cigarette paper increased by 20 CU. 2) Comparing with cigarettes without filter ventilation, filter ventilation reduced the air intake through cigarette paper by 2%-3%, and the maximum air velocity through the ventilation holes reached 0.83 m/s. 3) Filter ventilation, cigarette paper with high permeability and grooved filter changed the distribution of air intake through cigarette paper, so that more air tended to enter the cigarette from its rear half part. 4) The maximum air velocity in the grooves of a grooved filter reached 3.9 m/s, which was 10 times of that in the other parts.