![Sample our Physical Sciences journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/110819/TOC-Subject-Sample-2021-Physical-Sciences.jpg"})
Abstract
An experimental investigation of laminar smoke points of candle flames is presented. Adjustable wicks with diameters of 1.7–7.3 mm were used to measure smoke points in quiescent air for 14 different waxes. The measured smoke points increased with wick diameter. Smoke points interpolated to a wick diameter of 4.5 mm varied from 41–80 mm and increased from commercial waxes (candelilla, carnauba, beeswax, paraffin) to normal alkanes (hexatriacontane, octacosane, tetracosane) to primary alcohols (octadecanol, docosanol, hexadecanol) to carboxylic acids (stearic, palmitic, lauric, myristic). Wax smoke points decreased with increasing carbon number. Alkane and alcohol smoke points decreased with increasing fuel C/H ratio and correlated with past measurements of liquid fuels and polymers. Soot emission was not possible for any fuel when wick diameter was below 1.7 mm or when wick length was below 5.9 mm.
This research was supported by a Minta-Martin award from the College of Engineering at the University of Maryland. Helpful discussions with John L. de Ris and David L. Urban are acknowledged.
Notes
∗Additional details are as follows: beeswax, refined, yellow; candelilla, natural; carnauba number 1, yellow, refined.
†Melting points sources are as follows: commercial waxes (Sigma-Aldrich, Citation2007), all others (Lide, Citation2007).
‡Boiling points are at 760 mm Hg except where a different pressure is shown in superscript. Sources are: paraffin (Reed, Citation1997), alkanes and aliphatic alcohols (Lide, Citation2007), carboxylic acids (Speight, Citation2005).