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How will the laser achieve the Leidenfrost Effect[1] that’s necessary to atomize the liquid into droplets? [1] https://en.wikipedia.org/wiki/Leidenfrost_effect

How will the laser achieve the Leidenfrost Effect[1] that’s necessary to atomize the liquid into droplets? [1] https://en.wikipedia.org/wiki/Leidenfrost_effect https://en.wikipedia.org/wiki/Leidenfrost_effect

iamleppert 7y ago
Using a piezo electric element to rapidly create a stream of liquid droplets between two apertures, where the gap in the middle an IR laser is focused to evaporate each drop at the rate they are coming from the transducer. It’s possible to use IR laser light to evaporate water droplets without contact with a surface. See: https://www.usna.edu/MechEngDept/_files/documents/brownell_files/ICTAM%2016.pdf https://www.usna.edu/MechEngDept/_files/documents/brownell_f... but there are many other documented experiments.
- function_seven 7y ago
  The main component of "vapor" from e-cigarettes is the atomized liquid, not a gas. The laser would create extremely hot gasses that would not be pleasant to inhale. (Boiling point of propylene glycol is over 300°F, and glycerol is even higher.) There have been attempts to use a piezo element to create vapor without using a hot coil, but as far as I know, the results are not nearly as effective as the coil-and-wick method.
logfromblammo 7y ago
Not sure that's actually necessary. Ultrasonic/cavitation humidifiers create water droplet mists without a heated element. A piezoelectric ultrasonic transducer membrane vibrates faster than the speed of sound in water, and cavitation bubbles form that throw mist droplets into the air when they implode at the surface. Propylene glycol (0.042 Pa-s) and glycerin (1.412 Pa-s) are more viscous than water (0.001 Pa-s). But glycerol is essentially non-volatile below 310K, and the vapor pressure of propylene glycol is less than 1% that of water. But if you're not depending on heat-vaporizing the carrier solution, you could add water to make it cold-mistable by ultrasonic cavitation. Both of the usual bases are miscible in water. Your cold-mist e-juice would not be compatible with regular vaporizers. Maybe an impeller recirculating the fluid through a venturi could also lower the local pressure enough to help induce cavitation. I'm not sure how a laser would help, though.

iamleppert 7y ago

Using a piezo electric element to rapidly create a stream of liquid droplets between two apertures, where the gap in the middle an IR laser is focused to evaporate each drop at the rate they are coming from the transducer. It’s possible to use IR laser light to evaporate water droplets without contact with a surface. See: https://www.usna.edu/MechEngDept/_files/documents/brownell_files/ICTAM%2016.pdf https://www.usna.edu/MechEngDept/_files/documents/brownell_f... but there are many other documented experiments.

function_seven 7y ago
The main component of "vapor" from e-cigarettes is the atomized liquid, not a gas. The laser would create extremely hot gasses that would not be pleasant to inhale. (Boiling point of propylene glycol is over 300°F, and glycerol is even higher.) There have been attempts to use a piezo element to create vapor without using a hot coil, but as far as I know, the results are not nearly as effective as the coil-and-wick method.

logfromblammo 7y ago

Not sure that's actually necessary. Ultrasonic/cavitation humidifiers create water droplet mists without a heated element. A piezoelectric ultrasonic transducer membrane vibrates faster than the speed of sound in water, and cavitation bubbles form that throw mist droplets into the air when they implode at the surface. Propylene glycol (0.042 Pa-s) and glycerin (1.412 Pa-s) are more viscous than water (0.001 Pa-s). But glycerol is essentially non-volatile below 310K, and the vapor pressure of propylene glycol is less than 1% that of water. But if you're not depending on heat-vaporizing the carrier solution, you could add water to make it cold-mistable by ultrasonic cavitation. Both of the usual bases are miscible in water. Your cold-mist e-juice would not be compatible with regular vaporizers. Maybe an impeller recirculating the fluid through a venturi could also lower the local pressure enough to help induce cavitation. I'm not sure how a laser would help, though.