Fig 1.
ENDS schematic and temperature measurement set up.
(A) schematic of recent generation e-cigarette (blue arrows indicate air flow direction); (B) 3D drawing of internal atomizer with visible coiled wire heating element and central air flow channel. (C) Two thermocouples (TC) cemented to the top and middle sections of heating coil for measuring temperature; (D) Axisymmetric schematic view of typical atomizer configuration showing approximate locations of attached thermocouples. (E) A constructed fixture for measuring aerosol smoke temperature. The fixture holds the thermocouple in place in the center of the flow path.
Fig 2.
Coil temperature and corresponding power recorded by the EScribe software for the 25 W, 50 W, 100 W, and 200 W power settings.
Long dash dot dot green line: temperature for 25 W setting, long dash dot blue line: temperature for 50 W, long dash red line: temperature for 100 W, solid purple line: temperature for 200 W, round dot green line: power for the 25 W setting, dash dot blue line: power for the 50 W setting, square dot red line: power for 100 W setting, dashed purple line: power for the 200 W setting. The inset image shows a magnified section of the graph from 0–1 s; the inset uses the same line descriptions in the caption above.
Fig 3.
Coil temperature recorded by TCs and EScribe for two flow rates of 0 mL/s and 55 mL/s.
Long dash dot dot green line: temperature measured at the top section of the coil for the air flow rate of 0 mL/s, solid blue line: temperature measured in the middle section of the coil for the air flow rate of 0 mL/s, long dash red line: temperature measured by EScribe for the air flow rate of 0 mL/s, dot green line: temperature measured at the top section of the coil for the air flow rate of 55 mL/s, dash blue line: temperature measured in the middle section of the coil for the air flow rate of 55 mL/s, dash dot red line: temperature measured by EScribe for the air flow rate of 55 mL/s.
Table 1.
Recorded maximum temperature by thermocouple (TC) for different brand of atomizers (Ni 200, 0.15 Ω) with: Temperature control = 300 °C, power = 100 W, puff duration = 10 s, airflow rates of 0 mL/s and 55 mL/s.
Fig 4.
Aerosol temperature at the top section of atomizer and at the mouth piece of the e-cigarette.
Dot green line: temperature at the top section of the atomizer for the air flow rate of 0 mL/s, dash dot orange line: temperature at the top section of the atomizer for the air flow rate of 25 mL/s, dash blue line: temperature at the top section of the atomizer for the air flow rate of 55 mL/s, long dash dot dot green line: temperature at the center of the mouth piece for the air flow rate of 0 mL/s, long dash orange line: temperature at the center of the mouthpiece for the air flow rate of 25 mL/s, solid blue line: temperature at the center of the mouthpiece for the air flow rate of 55 mL/s.