Austarion

In any practical implimentation of water injection on cars, I have never seen the intake charge being reduced to zero degrees.

However if you can show me a real life example then I would love to see it.

The injection of water is a great way to suppress detonation. But remember that by injecting water.. you're reducing the amount of O2 in the combustion process.

Also remember that 50/50 water methanol mix is usually used for water injection. The latent heat of methanol, at 503 BTU/lbm, is also less that water, at around 1000 BTU/lbm. So you will need to inject more of the water/methanol mix to get the same cooling effect as pure water. This reduces that chance that the mixture will completely vapourise in the short time allowed.

Anyway, my point is that although, theoretically, you can say you can get a zero degree intake charge, in real life it's not going to happen.

it might happen with sub zero temps with iced water :P

Look, as i said to deeks, He is new on this forum and already tried starting on me twice... its not the way to blend into the community. and besides....







You need to have at least 50 posts to have a go at me :P

Chryzla wrote:You need to have at least 50 posts to have a go at me :P

You only had 50 posts about a month ago..

excuse me, i didnt post on Austarion for about 6 months while i went through some personal problems, all my net time (what little I had) was spent on getting SG community built up.

I left Austarion with 240ish posts.

If you insist on starting shit with me dont do it in the technical section wanker. PM me.

I'm not looking to 'start shit', I'm suggesting that if you are trying to refute someone's well-structured argument, your rebuttal should at least include some facts..

Just because AB hasn't posted much doesn't mean he has nothing valuable to add to the discussion, and just because you disagree with him doesn't mean he is getting 'high and mighty'. Post count means nothing, any retard can reply to threads with LOLs and increase their count very quicky.

no. you have a problem with me and I would like to also help you to extract the pole from your rectum.

Im no physics expert, never claimed to be, however ambient water (examples of this is about 24 degrees) will not cool to 0 degrees, it is a miss-leading statement.

I dont care about my post count, or if you wish to give me shit about owning a sigma. Not everyone on here owns a starion. We all like them but I personally dont like the cost they are to keep on the road. I will get one eventually.

Looks like you still have "personal problems" :roll:

Anyway.

AB, can you tell us about this 0 degree cooling, we all lay in wait...

extract from the "3rd book of scum, astrophysical anomalies"

- Page 862, Chapter 18 “the source of that unusual odour in your grandmas house”
- Page 875, Chapter 19 “relationship between black holes and mismatched socks”


This is something I have spent a lot of time thinking about and thru all my musing, research, ill conceived concepts and half baked ideas PTY LTD, I have come to the conclusion that a highly efficient water injection system is a very tricky thing to build, and even trickier to setup correctly. From my point of view some of the most important aspects that I can remember at the moment are (in no kinda order)
- level of atomisation
- amount of time the water has to cool the charge -VS-
- condensing on the side of the inlet and turning into water drops AND
- amount of times the mixture changes direction in the pipe work AND
- centrifugal force generated by charge changing direction
- temp of water
- accuracy of control (load sense seems to be the go)
- exactly 1.7 billion other things (I worked them all out, honest)

I had the privilege of being involved with a hurricane dust extractor project that for R&D purposes was built out of clear plastic and had a thermal camera pointed at it. Too much to type but quite interesting.
Anyway, in a nut shell, there isn’t much room. But aside from that, you need to make decisions based on practicality and budget. One thing I will say, I am totally opposed to water before the turbo, nozzles can fall apart and get ‘chewed up’ or block up and cause big water drops to hit the fins, and all the ones I have seen (that worked well) pitted the wheel like a sandblaster over time, except one that was pointed at the side of the bolt head on the shaft, but I still didn’t like that. Basically, 3 years of hunting for bits, gathering information and fooling around I believe I have one of the most reliable yet complicated but efficient (lets see you fit 3 contradictions in one sentence) water injection systems ever created. Now I just need a working car. I will give one little secret away, the 40psi in your spare tyre is good for something. Anyhoo, this is all sounding way to sensible for me, im gonna go smooch the outside of my managers office window. On the 3rd floor.

Your right about the spray hitting the side of the bolt head, I guess thats why I still have my original compressor wheel after 8 years.
As for latent heat of water it's a complicated thing to grasp in ones mind.
I guess it works on the principal of how a evaporative airconditioner works. As for cooling down the charge... that would help, but the main reason for injecting water is to stop detonation, which means you can raise the boost.
A.
:D

Well I want it so I can raise the compression, same thing I guess.

Yes, water will let you raise the compression, but to a limit.
I would rather go the other way, and lower the compression.
The Turbo raises the compression of a motor while under boost.
I think a Starion is around 8.5 : 1 with no boost ( don't quote me ).
But under boost, ( 10, or 11 Psi ) that same motor now has a compression
ratio of around 14 : 1 .
Due to the fact that the Turbo has now shoved in about twice the amount of what an Atmo engine would do , and then it is going to get squashed up in to the same space.
Hope that reads ok.
A.

The injection of water is a great way to suppress detonation. But remember that by injecting water.. you're reducing the amount of O2 in the combustion process.

That is correct, but it is negated by raising the boost another 5 or 6 Psi.
Water will let you do that.
The higher boost will contain more O2 and fuel.
Something that the ECU has to re-map.

Dammm... more programming.

A.
:D

man scum. you always make me burst out laughing.

i read a hot 4's article some time ago now about water injection. They actually put it too the test by instaling the setup on a CA18det powered silvia which was stock besides an exhaust, pod filter and fuel cut defender. i can't remember the article word for word or spec for spec but they came to the results that

water injection: you have to inject a water volume that is around 25% of the total fuel being used on full boost.

Water methanol: was around 45%

on the silvia they injected the jet before the turbo due to the fact that the car comes factory with a little front mount. injecting after the turbo was a failure, the water pudlled in the cooler due to lack of atomization. the same principle applies to T.B injection not as effective at atomizing the water/methanol mix.

the only other issue istrongly advised people on when setting up water injection is the following.

No.1 F.O.D foreign object damage. ie injector nozzles inside engines/turbo's.

No.2 too much water can cause mechanical lock. water doesn't compress like air therfore if you fill the cylinder up before the compression stroke it will seeze the engine,


after all that hot 4's said a properly thought out water injection set up will enable the owner of a CA18 or sr20 to run upto 16 psi on a stock motor with stock intercooler.