Jeez, haven't posted in probably half a year now. Let's see if I still know how to do this.
Just about any liquid fuel burns more cleanly and efficiently when fully atomized. The only problem is that many of the conventional ways of atomiozing a fuel are impractical for use in an engine. It has been suggested to boil the fuel prior to injection, but aside from the fact that it would be highly unsafe, it would be extremely difficult to develop an injection system to inject the fuel under great pressure while still keeping it in a gasseous state.
My proposal is for a fuel atomization system that uses ultrasound to atomize the fuel, which could be either port injected or directly injected (either way would yield much greater efficiency than conventional systems). This would also be a good technology to use on my idea for an Ethanol and Biodiesel hybrid engine [link], as it would ensure that the mixture of both fuels would be completely homogeneous.
I also know that ultrasound technology is used in certain types of humidifiers, and in fact that is what sparked this idea. I'll see if I can find a link.-- acurafan07, Dec 14 2008 Biodiesel/Ethanol Hybrid Idea D50_20Bio-Diesanol [acurafan07, Dec 14 2008] Wikipedia http://en.wikipedia...trasonic_humidifierWikipedia's article on ultrasound + ultasound humidifiers [acurafan07, Dec 14 2008] How do fuel injectors work? Are they just like perfume atomizers or is there something about them that even more finely disperses the fuel?-- bungston, Dec 14 2008 Well, wikipedia says a fuel injector is a "nozzle and a valve". As I understand it, fuel is squirted out under a certain pressure as a fine mist. Still quite far from fully atomized however.-- acurafan07, Dec 14 2008 I think I have seen humidifiers that use ultrasound, but I think that somehow this uses low pressure to facilitate conversion to vapor. Is there an analogous thing you know of that combines ultrasound and high pressure?-- bungston, Dec 14 2008 Hmm can't say as I know of one, but I haven't come across anything that suggests low pressure is needed. I linked the wiki's article on ultrasound and ultrasound as used in humidifiers, and it works by vibrating a metal plate which somehow nebulizes the liquid. Seems to me that would be just as effective at high pressure as low pressure, especially since it wouldn't be heat dependent (as in steam).
I assume the only difference in this application would be the requirement for much greater power because the atomization would need to be much more rapid.-- acurafan07, Dec 14 2008 Some issues: 1) Mixture distribution: Injectors spray the fuel broadly mixing somewhat evenly into the mass of induction air. 2) Volume: An ultrasonic fuel system will need to deliver anywhere from 5cc/m to 350cc/m spread over a similar area. 3) Changes in relative pressure: An ultrasonic system will need to deliver evenly into an atmosphere that varies 1bar or more. 4) Fuel Goo: Modern fuels are full of crud. An Ultrasonic system must resist the buildup of crud that does not vaporize. 5) System must function from -20c to 140c-- WcW, Dec 14 2008 Looks like there's a bit of patent literature in this area. See in particular patents classified with an IPC of F02M 27/08. Patents with this classification relate to: devices for combustion by sonic or ultrasonic waves-- xaviergisz, Dec 15 2008 random, halfbakery