ten percent water in one liter of petrol?

[Christ]

Still waiting on those references...

[drew1d]

Originally Posted by Christ

Still waiting on those references...

references? I don't have any. I don't know a lot about this stuff.

It just makes me nervous when I hear water and fuel. It sounds like McGuyver like stuff. Every instance I've encountered it, Water in the fuel has been negative.

But I'm on the forum to try and understand why that can be different.

[Christ]

Ok, now that that's cleared up, water in fuel without being specifically emulsified can be and normally is a bad thing.

Using water in the intake stream to help cool the combustion sequence and provide an extra charge is not a bad thing, but can be, if done improperly. The only real tuning required is "does it run right" tuning.

Specific emulsions have been tested to no end, so far, as fuels for different types of engines, which provide a power generation advantage in making the same power for less fuel (torque as energy per BTU of fuel consumed... it changes the BSFC map considerably), as well as lowered emissions per gallon of mixed fuel burned. (I believe the emissions rate is the same per gallon of fuel non-mixed, but for the complete emulsion, per gallon, the emissions rate is lowered). There are economy and power differences on a per-gallon basis, which is where the problems come in, when testing emulsions versus standard fuels.

Those links I posted earlier in the thread lay out some of that information for you, and you can find many many more on the same topics with quick searches on Google.

[aerohead]

May 1989 issue of AUTOMOBILE MAGAZINE's BASIC TECH,by Barry Winfield,page 42-43 gets into the water emulsion.
"Household detergents in concentrations of 0.25 to 1.0 percent of the fuel volume make a satisfactory emulsion."
"Testing has confirmed reductions of nitrogen oxide concentration by 90 to 95 percent in exhaust gas; at 50 percent water in emulsion,there is practically total elimination of nitrogen oxide.Carbon monoxide is reduced by about 60 percent."
"An engine with a high 12:1 compression ratio was put on a test stand,operating on high-test aviation fuel.Even so,knocking was not quite absent.The engine was set to 3,000 rpm.When a fuel emulsion of 90 octane gasoline with 30 percent water was substituted ,the engine speed increased to 3,600 rpm,a 20 percent increase in efficiency,while exhaust temperature increased from 1,400 to 1,600 degrees Fahrenheit,indicating improved combustion of hydrocarbons and carbon monoxide.There was no trace of knocking."
A Ford Falcon was operated on a 50/50 emulsion of 50-octane gasoline for 1,000 miles without a major mishap.
This procedure is applicable to Diesel and stationary powerplants,too.
It looks like the premise is octane enhancement.There is no mention specifically of mpg benefit.

[Christ]

Phil -
The MPG benefit would come from the number of miles traveled on the actual fuel, not the emulsion itself.

From what I've seen/read in various articles and sources, if I understand it correctly, the economy goes down with the emulsion as a whole, but when you consider the emulsion two parts, with the water being "neutral", the actual fuel economy increases.

In other words, if you got 50 MPG on straight gasoline, and 30 MPG on a 50% emulsion, only 50% of your emulsion is fuel, therefore you can extrapolate that you're actually getting 60MPG for the gasoline fuel you've used, and nil for the water.

Those numbers are fallacy, completely arbitrary, to express a point.

Of course, you also have to account for the extra energy used to emulsify the fuel with the water, as opposed to just using the fuel in it's current state.

[wumpus]

A pretty common hot-rodding modification is to add a water/methanol sprayer to inject water/alcohol into the intake vapor especially after a turbo but before it goes in the cylinder. This works well because heat is already a problem (the turbo cranked up the temperature compressing the air) and lowers knock issues (especially important if the boost was raised).

If you want to try DYI mixing oil and water, I would suggest looking to build a similar setup as above (with lots of know how already learned by the hot-rodders). Keep them separate until vaporized, then shove them both into the engine. My guess is that this would work especially well with a lean burn (heat issues and detonation).

[user removed]

Pretty sure Pop's B17 used a methanol-water injection when they went to war emergency power. Without the w-m mix the engine would blow apart in short order. Even with it the engine life expectancy was measured in hours of actual w-m injection.

Boost was something like 20 PSI at sea level. Much less strain at altitude.

regards
Mech

[Christ]

Man, I love engines whose life expectancy is measured in minutes rather than miles...

[aerohead]

Originally Posted by Christ

Man, I love engines whose life expectancy is measured in minutes rather than miles...

I found a "road test" of a P-51D by CAR and DRIVER from years ago.
Under the performance header they mentioned that the engine could be operated for 5-minutes at maximum power "under wartime emergencies."

[Christ]

online article or print? I'd like to see it if I could.