Stavros

...you injected nitrous (and the appropriate amount of fuel) in to an exhaust manifold on a turbo car at full throttle?

Would it ignite? (im not sure, i mean its hot in there, but thats not always enough, and flames in there, but dunno if its enough)

Would it ignite with such a bang it just blows the manifold/turbo to bits? (i dont know how fast/violent the combustion would be)

Granted its pointless, but just wondered how easy it combusts (as its rather cold) and how violently, as never played with it enough to know really.

focusv8

Before or after the turbo?

As if it's going to matter

.

SteveB

iTrader: (3)

Well if you spray nitrous onto a naked flame it'll put it out as if it were a fire extinguisher, works just like a carbon dioxide fire extinguisher

nilrem

to start, the auto ignition point(AIP) of nitrous oxide will need to be found - this appears to be rarer information than rocking horse rose food , then the avearge temperature of an exhaust manifold... if the manifold is a higher or very similar number, then you would expect the nitrous to ignite.

as an example, just using fuel :-

fuel has a AIP of 246°C
apparently exhausts are around 260°C

so theoretically the fuel would ignite on contact with the exhaust, however the fuel would also create a cooling effect... but thats about as far as i can go...

thats how i understand it...

Muska

Would you also need to know the IM (ideal mixture) for fuel to air/N2o?

If it's too far either side (ie too rich/lean) then nothing will happen.

Chip

iTrader: (3)

There is NO available AIP for nitrous IMHO, the simple reason being that the AIP refers to ignition as a exothermic reaction with the oxygen in the air IIRC, and given that nitrous does NOT burn, never has burnt and never can burn in oxygen, it doesnt have one.

It PURELY an oxidising agent, it gets to about 360 degrees (IIRC, im sure a web search will show the exact value, but bear in mind it will vary in a manifold as its pressurised) and brakes down into nitrogen and oxygen, so that WOULD happen in the exhaust, which would mean a bigger number of moles present and hence a higher pressure (PV=NRT and all that).


This potentially would mean that the liquid you had injected would turn into a gas, and split into two seperate gasses, which is a massively endomthermic reaction effectively (its actually more about the latent heat of evaporation than the reaciton where it splits, but im trying to simplify it into one reaction for our purposes)

Now this endothermic reaction would massive cool the exhaust gas, which in turn would mean that the turbo was less likely to spool,(again PV=NRT)

Potentially if you are running very rich (which is typical on a turbo car) you may find that this extra oxygen now available means more of a burn can occur from the unused hydrocarbons, which potentially is also exothermic and also could lead to an increased number of moles present, so again would spool it more, I suspect this effect would be minimal though anyway, so Id try and guess the effects of the other too more really, unless you use a wet kit and piss fuel in too, then things could REALLY get interesting, lol


Anyway, ignoring that third point you basically have two completely opposite things happening, and I dont know the relative amount of each one to determine if the net pressure in the manifold would go up or down in the exact circumstances you are referring to, experimentation would be the only way to know.

However, the most important effect IMHO would I imagine be that the thermal shock would shatter the blades of the turbine.

I dare say someone has tried it at some point, and the reason you never hear of anyone doing it again since is cause of that meaning it doesnt work.




So bottom line, to answer your question, you have mistaken Nitrous for something that combusts, so all the effects you think will happen, wont do so, and the effects you would get instead, I dont think will do what you want either.

nilrem

Chip-3Door

i forgot that ntrous is not combustable, but just adds a large ammount of oxygen into the cylinder and thats what burns... think thats where i went wrong... i.e. from the begining

thanks for clearing it up though!

Chip

iTrader: (3)

Yeah, other than absolutely every single word you said, you were spot on

nilrem

Chip

iTrader: (3)

To answer your question, rather than the tangent we went off at.

I dont know im afraid mate, never seen it tried like that, but you would need to be VERY careful not to get nitrous anywhere near the blades of the turbo as it would thermal shock it cold before it got a chance to burn, I guess if you added it progressively enough though, or mapped specifically, it could be possible, if you are injection the fuel too.

I see no advantage though over just adding it before the engine, so it combusts in the engine normally, generates a load of power to help you accelerate and then as a side effect spools the turbo quicker.

My T34 on my 3door spools quicker with the gas on than a T3 does without.

Gatecrasher

I vote for it goes BANG! and blows the manifold/turbo to bits

Red16

would have to be before as there is no manifold after the turbo

with regards to what would happen... i have no idea

dojj

iTrader: (3)

is this to work out some sort of anti lag then mr s?

Chip

iTrader: (3)

There cant be ANY other reason for wanting to have a go at putting fuel and nitrous into your manifold IMHO!

Stavros

No, wasnt for any application, esp not ALS, as correct me if im wrong (???) but even if it did ignite it wouldnt help any more than pre-engine nitrous injection.

Basically what i was wondering about someone else touched on about nitrous often blowing out a "normal" flame.

Most obvious (only!) thing i could think of as an example was a turbo manifold, as it has actual flames in it from the exhaust ports, and it has a lot of radiated heat without flame too, and wondered how the usual fuel/nitrous mix reacts to those sort of things.
Also wondered IF it does react, how violently.

I was giving myself a science lesson.

But then I fell asleep and dont care much anymore

Chip

iTrader: (3)

Fair enough!


The point at which it goes from "putting out" a fire to supplying oxygen for it is the point you can keep its temperature above 360 degrees or so, so in the exhaust manifold, would certainly be an oxidant and would help fuel burn

jb fletch

iTrader: (1)

to Chip, very interesting read & very impressed !

PMSL @ Stav falling asleep & not caring !