fe3tcourier

for a start, it should have read like this :

as your sentence expands to :

which doesnt make sense at all, however, not withstanding this and that...

Taking the assumption that water will find its way to the iat sensor if there is any non vapourised left when it gets there and cool it down disproportionately to be true :

I posted a methodology for measuring these effects directly in both this thread and the locked one.

The entire trouble with using those papers as proof that no cooling occurs is that THEY DID NOT SET OUT TO FIND OUT ABOUT THAT, and that subsequently THEIR APPARATUS WAS TOTALLY UNSUITABLE FOR MEASURING THAT EFFECT because THE WATER WAS INJECTED IMMEDIATELY BEFORE THE PORTS, and thus, DID NOT HAVE THE TIME/DISTANCE REQUIRED TO VAPOURISE. in short, ITS NO ------- SURPRISE THAT NO GAIN IN POWER WAS HAD ON THAT SETUP.

yes, which is a valid assumption given that :
A the water should be injected in that direction anyway
B that rain which has droplet sizes 3 or 4 orders of magnitude larger travels at much the same speed as the air its in, even when its only exposed to that air for a short distance close to where its observed

you assumed wrongly.

i've also stated that i personally wouldnt use this setup, and that its a hack for a poorly setup engine with some of, but not limited to :
too high a compression ratio
too high a boost level
too low an octane
too little quench
too little engine cooling
too small a turbo off the edge of its map
too little intercooling
too many sharp edges in the combustion chamber
too little fuel (perhaps oem ecu)
too much advance (perhaps oem ecu)

NO

YES

JD is not everyone, and few others have STEPPED UP TO THE PLATE AND SAID THEIR PIECE.

not only that but,

JD (and apparently yourself) have repeatedly ignored and not responded to
the methodology that i have posted
the assumptions that this discussion is based on
the fact that the "peer wanked engineering literature" is not relevant and shows NO DATA applicable to this discussion.

i like the "you cant manipulate surface area" quote. the other guy is right, JD is dead wrong on that.

have a read of these links from the above linked page that illustrate the point VERY well :

http://www.air-process.com/inlet_fogging.htm
http://www.amco.com/power_generation.htm

although quite amusing, this discussion is fairly pointless, as the main reason anyone with a decent setup would want to use this is to suppress knock when trying to run silly boost on pump gas. which it will do nicely. only a monkey with a td04 pushing 25psi into a 2l 7000rpm twincam with the shaft minutes from snapping with no intercooling and too large a piping and excessive money to waste on buying HP pumps and nozels etc instead of upgrading more appropriate parts like pistons, an intercooler, a bigger turbo etc would find the charge cooling a useful thing.

fred.

Tom-Guy

Fred, I can't follow what your methodology is? You yip yip yip like a small annoying dog, something about 30 feet of pipe when you wouldn't find half that much in a remote mounted turbo setup. Do you care to try again, and this time type intelligibly? You can get all pissypants about a their/they're typing mistake, but you've made the same or worse multiple times in this thread. Drop your bullshit and JUST EXPLAIN CLEARLY wtf you are talking about ONE TIME so we can all get it.

Thanks.

Which are?


No extra airmass inducted with water injection = no intake charge cooling. Welcome to basic physics.


Look into atomisation technology. There are very definite limtis/obsticles for things like gasoline, must less a fluid with a lot of surface tension like water. The average water injection rig runs, what, 60 psi? Some of the PWM units run up to or slightly past 100 psi? No one is playing with high pressures, like in the direct inject gasoline arena. 60-100 psi... you can't increase surface area, PERIOD, and if you think you can I want pictures of your personal gear.

fe3tcourier

doing a series of tests with the soon to be reprinted methodology will allow one to get a contour and possibly a function for the evaporative rates involved and their cooling effect. from that you can scale, stretch, extrapolate, etc the data to fit the circumstances that you will find on a real engine.

No, but i'll quote what i already bothered to type in for you again.

point them out. a comparable mistake would be their/there to/too/two etc ie, a word with a totally different meaning, not a spelling mistake or typo like i frequently make, and you have a number of in your post...

no, but here it is as i wrote it last time :

poor setup with ultra high iats, large diameter pipes taking a longer than optimal path, high pressure, fine mist

can you read?

who said they arent? i'm certainly not going to go nuts on a 3000psi system when a cheaper and more reliable setup by other means could be setup in a superior (wont run out all of a sudden) way. you are assuming that A no one is B if they were they would put it on the net C if it were up, it would be easy enough to find D it would be publicly available E a dozen other random things...

you seem to be suffering from tunnel (some one else hasnt done it so it cant be done) vision.

whilst looking back to find my quote, i found this

which explains where hitchy got his bad numbers from. if we give you the benefit of the doubt you are out by 6 orders of magnitude. 5 on a system choked by tiny plumbing. 7 on my engine...

heres the math (which i actually cocked up by 75% earlier) :

(diameter of the pipe/2)^2 * PI * length + plenum volume =
(((75mm/2)^2 * PI * 1000mm ) / 1000000 ) + 2 litres = 6.41786467 litres
http://www.google.com/search?hl=en&s...es&btnG=Search

rpm when you start to get boost*displacement in litres/2 (4 stroke) = 3000 litres per minute
/60 for seconds = 50 litres per second
6.4/50 = 0.128 seconds
= 128 000 000 nano seconds.

hardly the 10 or less your sentence read to me. i guess you could argue that you meant upto 999nanoseconds at which point any larger would produce microseconds. you are still WAY WAY out.

if it was rear mounted... with silly hot temps and silly large pipe... you have a full second for it to sit in that heat without evaporating at all, or at least not significantly...

still going to tell me i'm wrong? then go ---- yourself you arrogant ignorant fool otherwise, have a nice day :-)

fred.

talonator1488

.128 seconds is plenty of time for heat exchange to occur given the specific heat of water vs. the specific heat of air.

Tom-Guy

It's also a bullshit figure because we aren't spraying water at 3000 rpms and 0 psi. Do you know how much power the average 2 liter four cylinder makes at 3000 rpms? ASSuming that it is at 100% VE at that point in the powerband, which I ASSure you it is very much not.

Do either of you care to try to make a real world applicable point, as opposed to manipulating numbers until they say what you want, either intentionally or out of ignorance?


They don't do that ---- in a lab, either, Fred.

Try calculating the amount of airmass vs watermass you would require for all the water to convert into vapor given an infinite amount of time, Fred. I assure you that at 250 degree charge temps - MUCH higher than you will ever find in an already air-air intercooled setup - you will never bring any significant fraction of the water into vapor form. Just so you have figures to call me out on, I'm going to pull some figures out of my *** witrhout even doing any of the math: 15% water-fuel ratio (hardly anything), 250 degree intake charge temps (insanely high), over an infinite time (LOL - freebie for your cause!), 1% or less of the water changes state.


Have fun, provide all work, and make sure to account for the rpms, airmass, and VEs that you would find in a real world turbocharged application when they water injection would be operating. Good luck proving your complete failure to approach the boilling point of water for my amusement.

klyph

What I have gathered is this:

Water Injection is a band-aid for an improperly designed turbo system. Therefore, one would only need it if they lacked the the mental capacity to plan out a proper setup, or at the very least copy a setup that already works.

Water Injection allows you to bring your engine to the verge of destruction protected by a system that has a high probability of failure or malfunction.

Water Injection offers no benefit, it only serves to correct a flaw in the foundational design of the system, i.e. high IAT, poor tuning, etc.

With all that being said, who the ---- would bother? Design your turbo system to be efficient for your power goals and WI is pointless.

Tom-Guy

Not exactly.

Water injection is great for engine/chassis combos that require it. Say, for example, You have a CRX with a TT/Vitara D16. The limit of your traction is around 350 whp, and your knock limit on pumpgas is 350 whp. Sure, you can "do" it, but your engine is going to wear out a lot quicker due to the thermal loads involved. Rich men would run racegas... the middle class and lowrents would set up a water injection system for thermal safety.

You can discount your statement about water injection systems having a high probability of malfunction or failure... it's attached to a freaking car, dude, you aren't making the situation any worse than it already was.

Aside from those two points, for all other cases, you are correct.

USS

You're right on count one. Anybody with half a brain could figure that out. The only problem lies when you find out how tight and how much pressure is needed to make a difference.

For the second and third response I'll give you this - Sure, you may harness some fundamental principles of Physics... but that isn't everything in this equation. You obviously know nothing Chemistry... so I suggest you read up before you spit some bullshit out again.

talonator1488

Hey man Im sorry if I hurt your feelings but I know quite a bit about chemistry too. Im a mechanical engineering major and have taken plenty of both. Quit posting responses that confirm what I say.

Fredd=WINNER!!

omgbossis21

Water injection is a great option for those who cant afford race gas and live in areas where higher octane fuel is not available. Its also a great option if you want to raise your knock limit, add timing and add more boost (too make a good amount of extra power). Doesnt seem much like a band aid to me....