Method for evaluating aerosol mass of electronic cigarette

Abstract

The invention discloses a method for evaluating the aerosol mass of electronic cigarettes, comprising the following steps: (1) Measurement: an electronic cigarette is smoked to measure the particle size distribution and the particle numbers in the generated aerosol, and measure the volume flow rate C of the aerosol and the testing time t; (2) Data processing: based on the particle size distribution and number, the aerosol particles are classified with classifying diameter d.sub.i, and the corresponding average number concentrations n of the particles to classifying diameters d.sub.i are calculated; and (3) the generated aerosol mass is calculated according to the calculation formula for the aerosol mass of the invention.

Claims

1. A method for evaluating an aerosol mass of an electronic cigarette, consisting of the following steps: (1) smoking the electronic cigarette using a Smoking Cycle Simulator to generate an aerosol, wherein the aerosol comprises a plurality of aerosol particles having a diameter range of 4 to 1000 nm; (2) performing a real-time measurement on the aerosol using a Fast Particulate Spectrometer comprising a charger and a classifier to obtain initial data, wherein the initial data comprises an particle size distribution of the aerosol and a particle number of the aerosol, the plurality of aerosol particles are electrified by discharge via the charger, diameters of the plurality of aerosol particles are classified via the classifier; (3) outputting and processing the initial data to obtain an average number concentration n corresponding to a classifying diameter d.sub.i, a volume flow rate C and a testing time t, wherein the plurality of aerosol particles are classified with the classifying diameter d.sub.i, the classifying diameter d.sub.i is d.sub.1 to d.sub.38 having numerical values of 4.87 nm, 5.62 nm, 6.49 nm, 7.5 nm, 8.66 nm, 10 nm, 11.55 nm, 13.34 nm, 15.4 nm, 17.78 nm, 20.54 nm, 23.71 nm, 27.38 nm, 31.62 nm, 36.52 nm, 42.17 nm, 48.7 nm, 56.23 nm, 64.94 nm, 74.99 nm, 86.6 nm, 100 nm, 115.48 nm, 133.35 nm, 153.99 nm, 177.83 nm, 205.35 nm, 237.14 nm, 273.84 nm, 316.23 nm, 365.17 nm, 421.7 nm, 486.97 nm, 562.34 nm, 649.38 nm, 749.89 nm, 865.96 nm, 1000 nm, the numerical value of the classifying diameter d is an average diameter of the aerosol particles in grade i; and (4) evaluating the aerosol mass according to the following formula: $W=\underset{i=1}{\overset{38}{.Math.}}\left(\frac{1}{6}{d}_i^3{}_0{10}^{-21}n{}_{t_0}^{t_1}\mathrm{Cdt}\right)$ wherein W is the aerosol mass, with a unit of g; d.sub.i is the classifying diameter; .sub.0 is a assumed standard density of the aerosol particles, i.e., 1.0 g/cm.sup.3; n is the average number concentration of the aerosol particles corresponding to the classifying diameter d.sub.i, with a unit of/cm.sup.3; C is the volume flow rate, with a unit of cm.sup.3/s; t.sub.0 is a starting testing time point, and t.sub.l is a terminal testing time point, each with a unit of s.

2. The method according to claim 1, wherein in the step (4), the aerosol mass produced by the electronic cigarette for per puff is evaluated according to the terminal testing time point t.sub.l.

3. The method according to claim 1, wherein in the step (4), a sum of the aerosol mass produced by the electronic cigarette for multiple puffs is evaluated according to the terminal testing time point t.sub.l.

Description

EMBODIMENTS

(1) The following examples are combined to further describe the present invention, but not limit the invention.

Examples

(2) Two commercially-available electronic cigarette products are selected, being named as the electronic cigarette 1 and the electronic cigarette 2, respectively.

(3) A Smoking Cycle Simulator (SCS) is used to simulate the smoking of the electronic cigarettes 1 and 2, respectively, then, the generated aerosol are analyzed by a Fast Particulate Spectrometer (DMS500), respectively. First, the setting parameters of the SCS and the DMS500 as follows: SCS, puff volume of 55 ml, puff frequency of 30 s, and body temperature of 320 K; DMS, data collection frequency of 10 Hz, a secondary dilution ratio of 300:1. Of cause, other suitable working parameters also can be used. After the parameters are set, the electronic cigarettes are smoked, and each electronic cigarette is smoked for ten puffs. The particle size distribution and particle numbers of the aerosol generated from two electronic cigarettes are online and real-time measured, and at the same time, the aerosol flow rate C and the testing time t are measured. After the measurements are completed, the DMS500 will output a standard data file, and the data file is browsed using Excel, then being processed to acquire the following indexes, corresponding classifying diameters di to the aerosol particles, corresponding average number concentrations n of the aerosol particles to the classifying diameters di. Then, the calculation is made according to the following formula:

(4) $W=\underset{i=1}{\overset{38}{.Math.}}\left(\frac{1}{6}{d}_i^3{}_0{10}^{-21}n{}_{t_0}^{t_1}\mathrm{Cdt}\right)$
to obtain the aerosol mass for per puff of each electronic cigarette. The experimental results are shown in the following Table 1.

(5) TABLE-US-00001 TABLE 1 The data of the aerosol mass of two electronic cigarettes The number of Sample smoking Aerosol mass No. puffs W, g 1 1 0.976 10.sup.3 2 0.885 10.sup.3 3 0.874 10.sup.3 4 0.840 10.sup.3 5 0.820 10.sup.3 6 0.857 10.sup.3 7 0.820 10.sup.3 8 0.823 10.sup.3 9 0.856 10.sup.3 10 0.846 10.sup.3 2 1 0.940 10.sup.3 2 0.866 10.sup.3 3 0.831 10.sup.3 4 0.821 10.sup.3 5 0.813 10.sup.3 6 0.841 10.sup.3 7 0.816 10.sup.3 8 0.822 10.sup.3 9 0.851 10.sup.3 10 0.846 10.sup.3

(6) With the above data, either the difference in the aerosol mass for per puff of the same electronic cigarette or the difference in the aerosol mass of different electronic cigarettes may be compared. As shown in Table 1, the aerosol mass of the electronic cigarette 1 is slightly higher than that of the electronic cigarette 2.