Atomizing fuel with piezo transducers

[TGP37]

I noticed how water can be atomized around 22 kHz sound and effectively with only 20 watts per piezo transducer.

With one speaker per runner, each at 14v pushing a max of only 9 amps for all 6 piezo transducers, the load is low. Making it possible to recover more power from a better atomized fuel vapor.

It is a well known process for water atomization and is used for mineral extractions from what I can gather.

Fuel would obviously require a unique frequency to atomize, or maybe it is close to water's frequency.

I thought about directing the sonic waves towards the opposite side of the intake runner where there is a parabolic dish shape to reflect the waveform almost fully intact. Kind of like a sonic laser where sound waves are amplified by preventing the energy in the sound wave to dissipate outwards. The fuel saturated intake air would pass through the region and, hopefully, atomize better combustion. It would also produce a slightly cooler intake temp as atomizing draws heat like evaporation by encouraging rapid evap.

Meh, an interesting idea I thought I'd share and see what you guys think.

Because the soundwave is reflected back at the speaker, recycling the impulse ,amps needed to drive enough energy may be reduced greatly. Or only use the system during idle and lean cruise to maximize fuel economy.....we all love fuel economy with zero impact on performance.

[pocket-rocket]

Neat idea, but I would be too afraid one of the speakers would be sucked loose at high RPMs and kill my engine. Not only that, you would probably want to make your own intake so you could place them in such a way that they don't disturb the airflow inside the intake.

[gectek]

I am sure that airspeed, dramatic reduction/rise in air pressure, other noise created and other issues would negate any form of gain.

[AleroB888]

I noticed how water can be atomized around 22 kHz sound and effectively with only 20 watts per piezo transducer.

With one speaker per runner, each at 14v pushing a max of only 9 amps for all 6 piezo transducers, the load is low. Making it possible to recover more power from a better atomized fuel vapor.

It is a well known process for water atomization and is used for mineral extractions from what I can gather.

Fuel would obviously require a unique frequency to atomize, or maybe it is close to water's frequency.

I thought about directing the sonic waves towards the opposite side of the intake runner where there is a parabolic dish shape to reflect the waveform almost fully intact. Kind of like a sonic laser where sound waves are amplified by preventing the energy in the sound wave to dissipate outwards. The fuel saturated intake air would pass through the region and, hopefully, atomize better combustion. It would also produce a slightly cooler intake temp as atomizing draws heat like evaporation by encouraging rapid evap.

Meh, an interesting idea I thought I'd share and see what you guys think.

Because the soundwave is reflected back at the speaker, recycling the impulse ,amps needed to drive enough energy may be reduced greatly. Or only use the system during idle and lean cruise to maximize fuel economy.....we all love fuel economy with zero impact on performance.

I've heard of ultrasonic agitation of solvents to clean objects immersed in them, but not to atomize a liquid. Do you have a link to how that is done?

[TGP37]

This video is an example of water being atomized by 20Mhz sound wave. Filmed with a powerful microscope and shot at 15000 fps. This is atomizing a standing mass of water, which requires X amount of energy to produce Y amount of particles. Water already in a small droplet should atomize rather quickly so long as it is under the frequency long enough.

Inducing the frequency is another issue though. Piezos could probably tolerate the vacuum at idle and anything with substantial load will just have higher velocity. The piezo could be placed in a safe place, I thought about bolting them down just past the injectors, facing perpendicular to the air flow. So the reflection is recycled. They may even be designed to mount like a second set of injectors.

All that is done is emitting a moderate pitch soundwave into a runner. Or just mount 1 piezo on the top of the plenum and let the soundwaves propogate down.

Only interested in the operation during idle to increase efficiency. The amount of fuel used is minimal so the power needed should be on the low end.

Just need a piezo that can tolerate the operating conditions. Vacuum and heat. Generating the frequency is the easy part, a weekend radioshack project, with fine tuning knob (lol). Though I might prefer a laptop controlled generator and use the headphone out, run to an amp and test different freq under different sin wave types, square, sawtooth, smooth, etc.

This could be very interesting if a simple piezo on the plenum could even just atomize so much.

Another video example:

[gectek]

Imo the fuel is already atomized a great deal by the normal spray pattern and the filters on the injectors. That is the reason they are so close to the head port. They are no longer considered a "wet" manifold.

[TGP37]

Funny, i found this video. Seems others had thought of this before. I'm still interested though. I like how this guy uses an Ultrasonic Humidifier.

If my idea is correct, far less energy or time would be needed to further atomize fuel droplets already suspended in the air. Versus being in a full liquid state.

[gectek]

Liquid fuel would pool in the transition between the manifold and head and would cause problems. Most of the time you see this when you get too large of an injector for the engine at idle, or the spray pattern becomes contaminated and droplets form. The fuel is def not in a "liquid" state when its in the manifold. Unless you are talking about TBI.

[TGP37]

Imo the fuel is already atomized a great deal by the normal spray pattern and the filters on the injectors. That is the reason they are so close to the head port. They are no longer considered a "wet" manifold.

And subjecting that fine mist to the frequency should easily further the atomization. Better atomization means more productive use of the fuel. Might even add to a more stable burn allowing slightly more spark advance.

Basically just augmenting the injectors job.

[gectek]

In that small of an area and in that short of a time, it is HIGHLY doubtful. Esp with all the other pulses going on inside the engine. Air pulses as well as pressure changes. It could cause problems too.

You want to run more timing, you can do quite a few things to help. Keep cyl temps down with a cooler engine both with a proper radiator, cooling fan, t stat combo along with an oil cooler combo and a proper heat range plug with a good quench area on the engine. Keep the air as cool as possible and keep the heat in the exhaust gas. Those things will help more IMO than adding another piece to the puzzle.

It is indeed a good experiment, but I am highly doubtful there will be a welcome outcome.

[TGP37]

I agree the odds of making a revolutionary component is slim to none, but the idea has merit. I would first need to find solid data on how much mass can be atomized versus time and power consumed.

I can see a small droplet atomize further quickly considering the technology is used to atomize a larger collective mass of standing liquid.

Idling at 0.3 lb/min, 0.05 lb/min per runner, means 0.0034 lb/min of fuel per runner. The actual mass of fuel at one moment in the runner is fairly light. If a pool of liquid can atomize at X amount of time, a fraction of that mass should be very easy to push the limits of droplet size.




ehh, who knows. I gotta think on this.

[pocket-rocket]

I was waiting for the guys bench to go up in flames when he started pouring the gas vapor onto the driver board, lol.

[TGP37]

I was waiting for the guys bench to go up in flames when he started pouring the gas vapor onto the driver board, lol.

I did not notice that but I did consider the possibility of a flash over.

It hit me, design a runner to whistle like a flute would. Have it whistle at the frequency needed to atomize the fuel. No input power needed except for the very slight change in ve, if any at all.

In the runner the "mouth piece" rests on the wall first, behind it the chamber to make the soundwave. At the end of the chamber it opens to the runner to emit the sound into the fuel rich air. Like welding a flute to the runner and plumb the ends. or more like those NERF footballs that whistle, add one of those but made of tool steel.

No moving parts, no electronics, no sensors, completely contained within the aluminum/steel runner.

edit: even maybe make the tip of the fuel injector whistle and have the sound source right where it is needed most. Or just ahead of the injector, a small steel whistler....but tuned to the right frequency, that is critical. or else it is just a noise maker.

[gectek]

Impeding flow would be the next problem. As well as a potential vacuum leak. And it has to be impervious to fuel and any type of hydrocarbon and oil and possibly water.

[robertisaar]

reminds me of what i want to call a pulse jet?