Table 1.
Physical parameters of test cigarette samples.
| Parameters | Sample 1 | Sample 2 | Sample 3 |
|---|---|---|---|
| Circumference (mm) | 17 | 20 | 24 |
| Filter length (mm) | 30 | 30 | 27 |
| Tipping paper length (mm) | 38 | 36 | 35 |
| Visible tobacco rod length (mm) | 59 | 61 | 49 |
| Cigarette length (mm) | 97 | 97 | 84 |
| Cigarette paper permeability (CU) | 60 | 61 | 60 |
| Cigarette paper weight (g/m2) | 29 | 29 | 29 |
| Potassium citrate content (%) | 1.3 | 1.3 | 1.3 |
| Filter ventilation rate (%) | 25 | 26 | 26 |
| Tobacco density (mg/cm3) | 233 | 236 | 232 |
| Cigarette weight (mg/cig) | 913 | 683 | 534 |
| Draw resistance (Pa) | 1,441 | 1,242 | 1,016 |
Figure 1.
Measurement of the burning line position during smoking.
Table 2.
The average paper burning line positions of the three cigarette samples.
| Circumference (mm) | Lighting puff (mm) | Puff 1 (mm) | Puff 2 (mm) | Puff 3 (mm) | Puff 4 (mm) | Puff 5 (mm) |
|---|---|---|---|---|---|---|
| 17 | 5 | 11 | 20 | 30 | 40 | 50 |
| 20 | 5 | 9 | 16 | 24 | 32 | 37 |
| 24 | 5 | 8 | 16 | 23 | 30 | 38 |
Figure 2.
Distribution of mainstream smoke volume of a cigarette during puffing.
V1 : A mixture of the gas that is being produced in the combustion coal and air that is entering with a puff;
V2 : Air volume entering the remaining tobacco rod through the cigarette paper;
V3 : Air volume entering through the filter ventilation holes;
Figure 3.
A photo and a schematic diagram of the cigarette ventilation measurement device.
a: Soap film flow tube; b: Moveable sealing tube; c: Vacuum pump; d: Flow speed controller.
1. Movable piston; 2. Cylindrical cavity; 3. Labyrinth seal; 4. Rubber plug; 5. Labyrinth seal; 6. Cigarette; 7. Two-way valve; 8. Three-way connection parts; 9. Two-way valve; 10. Flow speed controller; 11. Vacuum pump 12. Rubber hose; 13. Soap film flow tube; 14. Rubber ball; 15. Test tube holder; 16. Iron support.
Table 3.
Comparing the results of the ventilation measurement device and a cigarette test station.
| Circumference (mm) | 17 | 20 | 24 | ||||
|---|---|---|---|---|---|---|---|
| Mean value | SD | Mean value | SD | Mean value | SD | ||
| Filter ventilation rate (%) | Designed device | 23.9 | 2.3 | 24.7 | 1.6 | 25.9 | 0.8 |
| Cigarette test station | 24.7 | 2.0 | 26.0 | 2.9 | 25.6 | 1.5 | |
| Absolute difference | 0.8 | 0.3 | 1.3 | 1.3 | 0.3 | 0.7 | |
| Total ventilation rate (%) | Designed device | 34.9 | 0.9 | 33.1 | 1.3 | 27.7 | 1.5 |
| Cigarette test station | 33.8 | 1.9 | 34.1 | 2.5 | 28.4 | 1.4 | |
| Absolute difference | 1.1 | 1.0 | 1.0 | 1.2 | -0.7 | 0.1 | |
Figure 4.
Total ventilation (ηt) of cigarettes with different circumference in (A) during smoking and (B) unlit as a function of puff number.
Figure 5.
Relative changes of the total ventilation of cigarettes with different circumferences compared to unlit cigarettes as a function of puff number.
Figure 6.
Variation in total ventilation and filter ventilation of cigarettes with different circumferences during puffing.
a No statistically significant effect; b Statistically significant effect.
Table 4.
Total ventilation and filter ventilation of cigarettes with different circumferences.
| Circumference (mm) | Ventilation (%) | Puff | Δη1 (%) | Δη2 (%) | |||||
|---|---|---|---|---|---|---|---|---|---|
| Unlit | 1 | 2 | 3 | 4 | 5 | ||||
| 17 | Total ventilation | 34.9 ± 0.9 | 45.4 ± 3.0 | 42.3 ± 3.6 | 36 ± 3.5 | 31.3 ± 1.4 | 28.4 ± 2.0 | 10.5 | 17.0 |
| Filter ventilation | 23.9 ± 2.3 | 28.8 ± 2.9 | 26.2 ± 2.2 | 25.1 ± 3.6 | 25.5 ± 3.4 | 23.3 ± 2.1 | 4.9 | 5.5 | |
| Cigarette paper ventilation | 11.0 | 16.6 | 16.1 | 10.9 | 5.8 | 5.1 | 5.6 | 11.5 | |
| 20 | Total ventilation | 33.1 ± 1.1 | 45.7 ± 2.3 | 42.7 ± 3.1 | 37.3 ± 3.3 | 34.4 ± 2.6 | 32.4 ± 2.9 | 12.6 | 13.3 |
| Filter ventilation | 24.7 ± 1.6 | 26.9 ± 2.1 | 25.6 ± 3.7 | 24.7 ± 2.9 | 24.3 ± 3.2 | 23.8 ± 3.3 | 2.2 | 3.1 | |
| Cigarette paper ventilation | 8.4 | 18.8 | 17.1 | 12.6 | 10.1 | 8.6 | 10.4 | 10.2 | |
| 24 | Total ventilation | 27.7 ± 1.4 | 41.9 ± 3.1 | 35 ± 2.1 | 32.5 ± 3.2 | 31.2 ± 3.9 | 29.5 ± 1.2 | 14.2 | 12.4 |
| Filter ventilation | 25.9 ± 0.8 | 29.8 ± 1.8 | 26.6 ± 2.0 | 26.5 ± 1.5 | 26.2 ± 2.0 | 25.9 ± 2.3 | 3.9 | 3.9 | |
| Cigarette paper ventilation | 1.8 | 12.1 | 8.4 | 6.0 | 5.0 | 3.6 | 10.3 | 8.5 | |
Table 5.
ANOVA (p-value) for the effect of puff number on temperature parameters of cigarettes with different circumferences.
Figure 7.
Comparison of characteristic temperature parameters of the combustion coal during puff-by-puff smoking of three cigarettes with different circumferences.
Figure 8.
TPM and H2O release of cigarettes with different circumferences during puff-by-puff smoking.
Figure 9.
The tobacco rod density along the cigarette axis of three cigarettes with different circumferences.