Wicking rates in electronic cigaretted.

Abstract

Electronic cigarettes (ECIGs) are devices used for nicotine delivery without combusting tobacco. They are marketed as a healthier alternative to regular tobacco cigarettes. While they have become increasingly popular in recent years, with continuously and rapidly evolving product design features and use behaviors, little is known about their safety and effectiveness particularly after volatile carbonyl compounds were detected in ECIG aerosol which are considered a major causative agent in pulmonary disease among tobacco cigarette smokers. These carbonyl compounds are postulated to be the result of what is known as the “Dry Puff”, where the heating element dries out and its temperature increases. Design features and user behavior highly influence carbonyl compounds emission and understanding these factors is relevant to regulating these devices. In this study, the properties of the wicking material used are studied and an experimental method was developed for this purpose, these properties along with principles of heat and mass transfer are plugged into a mathematical model that predict the saturation levels inside the wick or the wick dryness as a function of ECIG design feature and user puffing behavior. The model was run under different scenarios and the results were compared to experimental measurements. The predicted and measured values were strongly correlated, the results also revealed that the different factors affecting saturation levels in the wick were well captured in the mathematical model. Thus, this model can be used to predict the levels of wick dryness that are related to toxic emissions and help guide selection of ECIGs wicking materials, design and use conditions.