CORESTA Meeting, Smoke/Technology, Hamburg, 1997, ST14

A general smoke delivery model for parametric studies

Philip Morris USA, Research Center, Richmond, VA, USA
Numerous observations have shown that the smoke delivery of a cigarette is dependent on the design parameters such as length (puff number) and wrapper permeability. There are many smoke delivery models existing in the literature for conventional cigarettes and these models are reviewed. Although these theoretical models are appropriate to explain the observed experimental data, their focuses are usually limited to a few key design parameters. Furthermore, some models are mainly concerned with the single-puff delivery while the majority of experimental data are expressed as the total delivery of a cigarette. A combination of simple fluid mechanics and empirical equations obtained through regression analysis are proposed to provide a practical alternative to explore the effects of design parameters on the smoke generation and delivery of a cigarette. The general mathematical equation by considering dilution, diffusion, and filtration can be simplified to the gaseous phase delivery model, which was presented previously in the 1996 CORESTA Congress. In this work, we apply the general equation to tar. Thus, a simple integrated model is derived for the tar delivery of a cigarette, which is represented as a function of design and derived parameters such as coal volume and puff count. The design parameters considered in this work include filter parameters such as filter ventilation, wrapper parameters such as wrapper permeability, wrapper additive level and type, and wrapper basis weight, and construction parameters such as rod length, butt length, and circumference.