The Vapore-Jet pump developed by Vapore Inc., Richmond, Calif. (www.vapore.com), uses two fundamental phenomena, capillary force and phase transition, to vaporize a liquid and forcefully eject it as a gas. The small device could be used in camping stoves and small UAVs to pump vaporized fuel-and-air mixtures.
The device consists of three ceramic discs bound by a glaze on the outside surfaces. The top disc, called the orifice disc, is nonporous with a tiny hole in the center and posts projecting downward. The middle disc, the vaporizer, contains slots for the posts and is riddled with tiny pores and channels. The bottom layer, the insulator, is a larger-pored ceramic that resists heat flow.
In operation, the bottom layer is in constant contact with the liquid to be vaporized and pumped. Capillary action pulls the liquid up through pores in the insulator until it is prevented from going any farther by the vaporizer disc. Heat applied to the top disc travels to the vaporizer through the posts, where it heats the trapped liquid, increasing its volume by a factor of 100 as it transitions to a gas. This pressurizes the gas, forcing it out the orifice. Ejected gas is replaced by a cooling flow of liquid wicking up the insulator into the vaporizer. When properly designed, the result is a dynamic equilibrium of heat and liquid flow, gas pressure, and vapor.
The device is about the size of a watch battery and will work with naphtha, gasoline, kerosene, JP-8, diesel, and methanol. It also vaporizes nonfuel compounds for a host of applications including pesticide dispersion, fragrance generation, industrial processes, and even drug delivery.