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Wine_maker
14th November 2012, 08:43 PM
Hi folks!

One of my coworker is an old great well educated and very experienced combustion engineer. And once he mentioned in passing about the system that he used in his own car far years ago. It was quite unusual for me and I asked him to tell more about it.

Hi made it and then used it for several years (DIY “direct water steam injection” in carburettor of his car).

Let’s leave the technical details of his system for late discussion (or ask me and l’ll post the description) but when I tried to find similar information about it I found that was real technologies that were used many years ago for petrol, diesel and aircraft engines and then was forgotten.

Here is a direct link to wiki: http://en.wikipedia.org/wiki/Water_injection_%28engines%29

And the most important quotation for lazy riders LMAO:

In internal combustion engines, water injection, also known as anti-detonant injection, is spraying water into the cylinder or incoming fuel-air mixture to cool the combustion chambers of the engine, allowing for greater compression ratios and largely eliminating the problem of engine knocking (detonation). This effectively increases the octane rating of the fuel, meaning that performance gains can be obtained when used in conjunction with a supercharger, turbocharger, altered spark ignition timing, and other modifications. Increasing the octane rating allows for a higher compression ratio which increases the power output and efficiency of the engine. Depending on the engine, improvements in power and fuel efficiency can also be obtained solely by injecting water. Water injection may also be used to reduce NOx or carbon monoxide emissions.

Many water injection systems use a mixture of water and alcohol (approximately 50/50), with trace amounts of water-soluble oil. The water provides the primary cooling effect due to its great density and high heat absorption properties. The alcohol is combustible, and also serves as an antifreeze for the water. The purpose of the oil is to prevent corrosion of water injection and fuel system components. [2] Because the alcohol mixed into the injection solution is often methanol (CH3OH), the system is known as methanol-water injection, or MW50. In the United States, the system is commonly referred to as anti-detonant injection, or ADI.

In a piston engine, the initial injection of water cools the fuel-air mixture significantly, which increases its density and hence the amount of mixture that enters the cylinder. The water (if in small liquid droplets) may absorb heat (and lower the pressure) as the charge is compressed, thus reducing compression work. An additional effect comes later during combustion when the water absorbs large amounts of heat as it vaporizes, reducing peak temperature and resultant NOx formation, and reducing the amount of heat energy absorbed into the cylinder walls. This also converts part of combustion energy from the form of heat to the form of pressure. As the water droplets vaporize by absorbing heat, it turns to high pressure steam (water vapor or steam mainly resulted from combustion chemical reaction). The alcohol in the mixture burns, but is also much more resistant to detonation than gasoline. The net result is a higher octane charge that will support very high compression ratios or significant forced induction pressures before onset of detonation.
Fuel economy can be improved with water injection. Depending on the engine, the effect of water injection, with no other modification, like leaning out the mixture, may be quite significant or rather limited and in some cases negligible.

In some cases water may also reduce CO emissions, this might be attributable to the water-gas shift reaction, in which CO and H2O shift to form CO2 and H2. However, water may also increase hydrocarbon emissions, possibly due to an increased quenching layer thickness.
Some degree of control over the water injection is important. It needs to be injected only when the engine is heavily loaded and the throttle is wide open. Otherwise injecting water cools the combustion process unnecessarily and reduces efficiency.
Direct injection of water is possible and is likely advantageous. In a piston engine, this can be done late in the power stroke or during the exhaust stroke.

A limited number of road vehicles with large-displacement engines from manufacturers such as Chrysler have included water injection. The 1962 Oldsmobile F85 was delivered with the Fluid-Injection Jetfire engine, which, incidentally, shares the title of "the world's first turbocharged road car" with the Corvair Spyder. Oldsmobile referred to the water/alcohol mixture as 'Turbo-Rocket Fluid'. Saab offered water injection for the Saab 99 Turbo. With the introduction of the intercooler the interest in water injection disappeared, but today, water injection is also of interest because it can potentially decrease nitrogen oxide (NOx) emissions in exhaust. The most common use of water injection today is in vehicles with aftermarket forced induction systems, such as turbochargers or superchargers. Such engines are commonly tuned with a narrower margin of safety from detonation and hence benefit greatly from the cooling effects of vaporized water.

Then I found company that produce equipment that can be apply this old technology with modern engines.

For example: http://www.snowperformance.net/

With this product: http://www.snowperformance.net/stage-3-gasoline-mpg-max-boost-cooler.html

http://www.snowperformance.net/product_images/product-large_image-76.jpg



The DYNO tests:

Diesel engine:

http://www.snowperformance.net/product_images/dyno_chart-large_image-4.jpg

Petrol engine:

http://www.snowperformance.net/product_images/dyno_chart-large_image-2.jpg


What's your opinion?

BigRAWesty
14th November 2012, 09:35 PM
I did run a system but I didn't find it worked on my engine. It was stumbling at 3000rpm and blowing white smoke.. Turned it off and all good again... It was a basic $10 setup though..
I can see its theory and have read heaps of positive outcomes.. But yea, it didn't work for me..

A nice couple of vids of its potential..
http://www.turbomirage.com/water-alcohol-injection-videos.html

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

04OFF
14th November 2012, 10:20 PM
About 15 years ago I played around with home made multi stage water/meth systems, i ran it for about 10 years on my draw thru Turbo 6, it can take a very long time to perfect, but once sorted, you can get fantastic results, water/meth allowed me to run up to 10psi more boost with no other mods :biggrin:

taslucas
15th November 2012, 07:45 AM
They use Hi-tech water injection systems on high performance street cars. I was reading an article in a (australian) street car magazine a year or so ago and it showed how to make your own system including how to calculate the volume and pressure of the water/meth mixture that you need.
Sounds like it works well.
They also had photos of the combustion chamber with/without water injection. The chamber shown with water injection was a whole lot cleaner than than the one without.

Wine_maker
15th November 2012, 04:52 PM
My co-worker made a very simple system:
water tank then copper coil tube with 3-4 coils twisted around exhaust manifold (tank must be a little bit higher than copper coil tube) then tube leading to the carburettor and a nozzle on the end of the tube. Nozzle diameter for his car was experimentally chosen as 0.7 mm. When it was cold he filled the tank with the cheapest vodka (0.3 AUD per 0.5 L). The water consuption was 1.5 L of water for 15 litters of petrol for 1.6 engine.

taslucas
15th November 2012, 04:59 PM
The one I was reading about was on a fuel injected car so was plumbed into the intake manifold. The water wasn't heated though, just pressurised so that it would atomise

Tap, crackle, pop

Wine_maker
15th November 2012, 05:38 PM
In his system the water intakes into engine as steam after heating on exhaust manifold coils.

Chris79
15th November 2012, 08:36 PM
I worked with subaru's and used to see it from time to time on early WRX's, used to use the washer bottle as the tank lol.
One common issue with Subaru Boxer engines was that they always carbon up. Sometimes after a long spell with out having upper engine cleaner run through they would run poorly and cut out because of it, we would hook up water injection that would clean them out quick smart. Very effective.