Gas flow and filter ventilation of an unlit cigarette: model building, numerical solution and experimental validation

Understanding the fundamental relationship between gas dilution rate of a cigarette and key cigarette design parameters is important in the overall control of smoke yield. In this work, an equation was derived to express the total gas dilution with the cigarette rod length, cigarette paper air permeability, and the filter ventilation level. The relationship was validated using experimental results. The accuracy of the developed model was dependent on the regression method used, i.e., linear or a nonlinear. The expression provides a quantitative description of the interactions between filter ventilation level, cigarette length, cigarette circumference and cigarette paper air permeability and the total air dilution at the cigarette's mouth end.