CORESTA Meeting, Smoke Science/Product Technology, 2019, Hamburg, ST 39

The mechanism of evaporation in conventional wick-and-coil e-cigarettes compared to an alternative volumetric heater approach

SCHMIDT R.; KESSLER M.
HAUNI Maschinenbau GmbH, Hamburg, Germany

Conventional electronic cigarettes facilitate the so called wick-and-coil-systems for liquid evaporation. This technology shows essential drawbacks inherent to the system. Due to the non-uniform temperature distribution throughout the heated volume there is an erratic risk of liquid getting overheated locally. Overheating causes the emission of carbonyls and metals and can neither be overcome by automated production of the nowadays typically handmade cartridges nor by sophisticated control algorithms of the power supply, which will be shown and discussed within the presentation in detail.

The aim of this study is to compare the characteristics of a newly developed volumetric heater to conventional wick-and-coil-evaporators and show its potential.

Within the study the differences between both evaporation methods will be described and underlined by comparative testing. For the volumetric heater system, total particulate matter (TPM) consistency, droplet size distribution and carbonyl assessment will be presented. It can be seen that the amount of hazardous substances can be reduced significantly compared to conventional wick-and-coil systems operated at comparable vapour emission. The benefits of the volumetric heater approach for use in electronic cigarettes as well as a door opener to precise inhalative dosing applications will be discussed. It may also serve as a reference method for testing e-liquids under precisely controlled conditions.