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Which water injection system?

Very cool stuff, and i do have a little chemistry under my belt as well... I can agree that from a pure organic stand point using water as "fuel" is impossible without electrolosis, but strange things happen under compression that we havent looked into in particular (where i go to school at least). So i can't comment on how much compression would be necessary to break H2O bonds, but its not completely impossible under the high combustion temperatures + high compression that the hydrogen - oxygen bonds could be broken and assist in unburnt diesel fuel (that doesnt have the necessary oxygen to burn)... useing the oxygen to assist in buring the diesel, and using the hydrogen as a fuel that quickly reforms into H20 and C02 that exits the exhaust pipe.

I'm sure a couple equations could prove that this doesnt happen, but it doesnt mean that it isnt happening on a micro scale...

The micro scale is also extremely hard to prove since one of the products of combustion (H20) is exactly what is going into the engine.

I know i'm going to have a lot of strong stands against this, but on a micro scale (chemically speaking) for this situation in which H20 contains all that is necessary for combustion really anything is possible when compression and high temperatures are involved.... Again.. strange things happen under compression... especially when it is already in gaseous form.

Also, i agree with H20 increasing the density in the combustion chamber and increasing the "mixing effect" to create a more atomized mixture that is easier to combust due to more uniform mixture throughout the chamber.

Either way, it makes for a more effective burn... John Deere was even doing this way back in their early years.

Thanks for the input
 
Water flashing to steam does not produce energy. eg. water setting at room temp in a pressure cooker doesn't boil producing steam until you add heat via the stove. The heat energy added is basically converted to energy in pressure. If you ignore any heat lost, it's an overall energy neutral/conserving system.

Same deal in the engine combustion chamber. Any water that's still liquid upon getting into the combustion chamber is driven thru the phase change (from liquid to gaseous/vapor/steam) by absorbing heat energy present the combustion chamber. That energy isn't lost - just converted from heat to pressure.

Any reaction starting w/ H2O & producing energy (from H2 & O2 derived from injected water) would have to result in molecule(s) of lower overall energy state than H2O.

H2O & CO2 are pretty much at the bottom of the "nature's molecules" energy ladder. So plants take them in, using solar energy via photosynthesis to build more complex molecules & compounds (that store the energy in their chemical bonds) until we burn/combust them to get some energy out.

Now there has been some research into possible engine efficiencies gained by utilizing water to recover waste/excess heat in situations where there appears to be extra heat in the chamber that's not contributing to useful work pushing the piston down. This concept isn't really improving or even effecting combustion efficiency. It's recovering heat energy in the chamber that (or whatever reason isn't) doesn't seem to be producing additional work w/o water injection.

I've also seen one article suggesting when methanol & water change phase liq to gas, it enhances/increases the surface area of diesel droplets, thereby enhancing the air/fuel interaction necessary for combustion.

There's also research showing low percentage water/fuel emulsions can improve the soot formed : NOx formed trade-off. Typical EGR strategies to lower NOx production via lower cylinder temps result in more soot production.

My point here isn't to say water injection can't impact fuel economy. Just saying the injected water isn't contributing hydrogen & additional oxygen that can participate/add to the combustion reaction. Any economy change must be from some other mechanism.
 
Touche. I'll agree with you, the 2H20 --> 2H2 + 02 --> 2H20 reaction is energy in = energy out, so really you are right that no matter what is going on whether that reaction occurs or not, its in equilibrium, and even if it somehow did contribute to a diesel fuel combustion reaction the gains or losses would be to small to notice.

As for the paper, that would make perfect sense since its a hydrophillic liquid being mixed with a hydrophobic liquid would ... in theory... create either a mass of diesel one one side, and water on the other OR under heavy mixing (lots of air being rammed in along with compression) it potentially could create a mixture that wants nothing to do with its partner molecules. So essentially it could create a uniform diesel-water mist that fights against eachother ... separating the molecules into smaller units, increasing the surface area of the diesel (as you mentioned) resulting in a more efficient burn, and since water is a byproduct of the burn, no harm is done to the environment.

According to Heath, he sees no black smoke ever with a water injection system, so logic would say that the paper would have some merit.

Thanks again
 
This is heath running water, or Methanol?

If the air charge is Denser, the lower IAT's and denser air may be the difference there for no black smoke. You are getting more air which will clean up the smoke.
 
I would not recommend straight water as a low percentage methanol will keep the system free of algae and fungus. Heath can only run water on the track.
 
That was my understanding too (straight water)... When i talked to a guy yesterday on the phone he claimed when they tow with one of his built trucks he uses:

1 Gallon water : 1 Gallon diesel

(approximately), so he's spraying it pretty damn good.
 
buddy said:
I would not recommend straight water as a low percentage methanol will keep the system free of algae and fungus. Heath can only run water on the track.
Click to expand...

That's a good point and something I had not really thought about but this is directly from Heath's site.

"As a rule we use only pure water in the 6.5 and recommend against addition of methanol, unless by carefully controlled use."
 
Well he cant recommend using something that could hurt your engine. If you run 25% methanol it will be a problem. 10% methanol I have run just fine. I put a half gallon of windshield washer fluid in to 4.5 gallons of distilled (or at least filtered) water. Small injectors. Large inectors are a bad idea too. Of course I dont really do anything special to mix the methanol in the tank, but fiugre it gets a good amount of sloshing.
 
buddy said:
I would not recommend straight water as a low percentage methanol will keep the system free of algae and fungus. Heath can only run water on the track.
Click to expand...

According to my last conversation before I bought mine last year (yet to be installed) from him, he only runs water, and always uses just water in his burb, and the Bonneville racer which is his tow vehicle, says he fills fuel and water tanks at same time from what I gather he sprays at >2 psi boost, and the controller adjusts flow proportional to boost, more boost, more spray.
 
buddy said:
Well he cant recommend using something that could hurt your engine. If you run 25% methanol it will be a problem. 10% methanol I have run just fine. I put a half gallon of windshield washer fluid in to 4.5 gallons of distilled (or at least filtered) water. Small injectors. Large inectors are a bad idea too. Of course I dont really do anything special to mix the methanol in the tank, but fiugre it gets a good amount of sloshing.
Click to expand...

Methanol is miscible in water so no worries about it mixing. Miscible means the components form a homogenous mixture regardless of each component's percentage.

Methanol is corrosive to aluminum but not a problem at these lower % mixes w/ water injected. If the water injection setup is also plumbed to spray an IC core's exterior (to gain some additional IC efficiency), it can accelerate IC exterior corrosion when higher % mixes.

If using 1 gal water per 1 gal fuel, it sounds like carrying a significant amount of additional weight in water. Are some folks putting in 20-30 gal water tanks?
 
SmithvilleD said:
Are some folks putting in 20-30 gal water tanks?
Click to expand...

Heath's burban has a 50 gal water tank and he told me other people running his system like he does use RV holding tanks mounted under the truck. I asked him where he sourced his tanks since he doesn't sell them. I was looking for something to go under the hood when he started explaining to me how he runs it. This is how we started talking about WI in the first place.
 
Are some folks putting in 20-30 gal water tanks?


I'm not using any methanol, just straight water and I use quite a lot also. The 7 gallon tank is used up too fast. Installing a 10"x12"x63" 32 gallon water tank. On top of that will be my 12"x48" 23 gallon propane tank. These will be mounted in front of my tool box where the propane control system is located.
 
I've heard of people using 4" or 5" Plastic pipe along the framrail too w/caps to make a tank.

Someone with math memory better than mine. Need the area of a cylinder 4" x 5'. Converted to gallons.
 
Well I am curious what MPG of water/meth people are getting then cause that will help me find out how big of a tank I need? Being that I have a suburban I will have to mount the tank underneath the truck so filling will most likely be a pain in the ass so if it really uses that much I will have to find a larger tank than I was planning on useing. I only plan on having it kick in over 5 psi for help on hill pulls more than constant for the MPG factor.
Plus I will be running a 50/50 mix since I can get that for free or should I water it down?
 
saturntech95 said:
Well I am curious what MPG of water/meth people are getting then cause that will help me find out how big of a tank I need? Being that I have a suburban I will have to mount the tank underneath the truck so filling will most likely be a pain in the ass so if it really uses that much I will have to find a larger tank than I was planning on useing. I only plan on having it kick in over 5 psi for help on hill pulls more than constant for the MPG factor.
Plus I will be running a 50/50 mix since I can get that for free or should I water it down?
Click to expand...

Bill has a 50 gallon plastic tank behind his middle seat.

My system comes on at 2 pounds, but this is not a very large amount, just a small percentage. At 10 pounds of boost the second stage comes in and again that is not a large abount either. A lot of boost is required to get 100%.
More boost more water is being injected.

I'm not going to be the first one to chime in on this but I would highly suggest you to not go over 10 percent methanol. If you can get 50/50 for free then sell the excess!
 
Matt Bachand said:
I've heard of people using 4" or 5" Plastic pipe along the framrail too w/caps to make a tank.

Someone with math memory better than mine. Need the area of a cylinder 4" x 5'. Converted to gallons.
Click to expand...


Not area, volume. 754 cubic inches/231(cubic inches in a gallon) = 3.26 gallons = not a lot.
 
volume of a cylinder is the area times the height, thats what Matt meant. pi times radius squared times height.

I would not run more than 10% methanol. I use it mainly to keep the system clean and if you are on the edge of frosty climates or going up the moutains it can keep your water from frosting.
 
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