<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The burning cycles of a lit-end cigarette were numerically simulated using a 3-D model that includes both the cigarette and its surrounding ambient air and the effects of buoyancy forces. The solid and gas phases were treated separately in a thermally non-equilibrium environment. The tobacco pyrolysis and char oxidation were modeled using multi-precursor models. The changes in tobacco column porosity and its subsequent effects on permeability and gas diffusivity were included. The mass, momentum, energy, and species transport equations were solved in a discretized computational domain using a commercially available computational fluid dynamics (CFD) code. The model was applied to puff a cigarette under different puffing intensities and the effects of puff volume, puff profile, and puff duration were studied. The results show that the model is capable of reproducing the major features of a burning cigarette during both smoldering and puffing. For the puffing and puff-by-puff cases, the solid and gas temperatures as well as those mainstream smoke constituents predicted by the model are in a good agreement with experimental results. A parametric study shows the significant effect of puff volume, puff profile, ventilation rate, and puff counts on solid and gas phase temperatures as well as gaseous species concentrations and mainstream smoke delivery. The buoyancy forces have shown to be very important in both smoldering and puffing.</p></abstract>

The burning cycles of a lit-end cigarette were numerically simulated using a 3-D model that includes both the cigarette and its surrounding ambient air and the effects of buoyancy forces. The solid and gas phases were treated separately in a thermally non-equilibrium environment. The tobacco pyrolysis and char oxidation were modeled using multi-precursor models. The changes in tobacco column porosity and its subsequent effects on permeability and gas diffusivity were included. The mass, momentum, energy, and species transport equations were solved in a discretized computational domain using a commercially available computational fluid dynamics (CFD) code. The model was applied to puff a cigarette under different puffing intensities and the effects of puff volume, puff profile, and puff duration were studied. The results show that the model is capable of reproducing the major features of a burning cigarette during both smoldering and puffing. For the puffing and puff-by-puff cases, the solid and gas temperatures as well as those mainstream smoke constituents predicted by the model are in a good agreement with experimental results. A parametric study shows the significant effect of puff volume, puff profile, ventilation rate, and puff counts on solid and gas phase temperatures as well as gaseous species concentrations and mainstream smoke delivery. The buoyancy forces have shown to be very important in both smoldering and puffing.

Mathematical Modeling of a Lit-End Cigarette: Puffing Cycle and Effects of Puff Counts

Saidi Partnership, Richmond, Virginia, USA

Philip Morris USA Research Center, Richmond, Virginia, USA

Contributions to Tobacco & Nicotine Research

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The burning cycles of a lit-end cigarette were numerically simulated using a 3-D model that includes both the cigarette and its surrounding ambient air and the...

Mathematical Modeling of a Lit-End Cigarette: Puffing Cycle and Effects of Puff Counts

Pubblicato online: 30 dic 2014

Pagine: 46 - 62

Ricevuto: 20 dic 2006

Accettato: 18 gen 2007

DOI: https://doi.org/10.2478/cttr-2013-0847

© 2008 Beiträge zur Tabakforschung International

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.