Supercharger theory
Turbo Mini Forums

Just read this on another forum. I can't quite get my head round it. It dosen't seem right, maybe a refrigerator expert could help explain.

"the suck through kits dont really run that much heat due the the fuel/air mixture being sucked through the carb coursing the temp of the inlet charge to drop a lot inlet pipe can get very cold to the point of icing on out side of the pipe

so the temp of the fuel air going in is so much much colder than the ambant air temp that by the time has been compressed is not that hot

can put your hand on the supercharger when running and is only warm to the touch did think about putting a air temp sender in the manifold of last suck through but never got round to it "

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

TMF by any chance?

If something is worth doing, it's worth doing half of.

Ha Ha

It's right for running at idle, but elsewhere it's bollocks.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

I will agree with that.

bloody simpletons, tell him to do a junction or two on the motorway and then try to touch it, but make sure he films it and posts it on here for a laugh. His names not Cleatus by any chance?

Quote this:


That explains expansion cooling as well as temperature rise due to compression.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

http://www.fastforwardsuperchargers.com/mi...erchargers.html

wil , in a doctorate thesis i read recently ,the writer achieved a 22 degree drop in temp by putting the inj about 20 inches from the head ,

i seem to remember reading an article on the design of the merlin engine for the spitfire ,where ,by using a carb and running the fuel through the twin stage supercharger ,they achieved significant intercooling ..there where some graphs ill see if i can find it .

regards
robert

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Ummm......

The problem with using fuel to intercool is that in the process of cooling the air it vapourises.

As it vapourises, it expands dramatically thereby precluding the air carrying the oxygen it needs to make power.

End result.... I think.....cooler charge but no more power.

Really need back to back tests with a proper intercooler to prove.

Edited by Paul S on 26th Mar, 2009.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

what happens when you cool air ?

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

so if its trapped between the supercharger and the inlet valves ,boost will rise and the charge will get cooler ?

wil ,heres another link

http://www.thedrivenman.com/AJ6/superchargers.html

heres a bit from it PRESENT-DAY SUPERCHARGING -

It seems even now to be a little recognised fact that adding just a proportion of the fuel before the supercharger is a very effective method of lowering charge temperature by evaporation during compression, as well as being a good method of mixture preparation. There is an efficiency gain here which is not immediately obvious. Cooling the charge as it is compressed is of more benefit than any form of cooling after the event (by an inter-cooler for instance, although further charge-cooling may still be beneficial) because the work consumed by the compressor will be reduced. Water or water/methanol injection can be used for the same purpose. This important advantage is denied to the Roots device because of its lack of internal compression. Stanley Hooker estimated that adding fuel ahead of the supercharger dropped the air temperature by 25 degrees C on the Merlin, enabling it to consistently outperform the larger and supposedly more advanced German engines with direct fuel injection into the cylinders. Fuel has to be added anyway so why not add it where it will do most good?

Edited by robert on 26th Mar, 2009.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Anyone got an entropy-enthalpy diagram for petrol.

I could then work it out to be sure.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Edited by Paul S on 26th Mar, 2009.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

i was pointing out the paradox paul lol
i feel that boost would actually in reality get lower as the charge contracts ,and to maintain the same boost the blower would have to spin faster so creating more flow and power .sorry ..should have put a q mark on it .
anothe factor is that running fuel thgrough a rootes type blower ,is purported to close up tolerances and so incrrease efficiency , i know that a large amount of the fuel in top fuel is inj before the blower for these sort of reasons ,although i think they are now using the psi blowers ,or were they banned ,cant remember now ..to busy porting .

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

I'm begining to think Paul S is just a giant cerebral cortex in a big jar, but with a suitable appendage to operate spreadsheets.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

while I am a refrigeration technician, and understand the processes involved, I am not clever enough to quantify anything other than to say, that there will be a small chilling effect of the fuel evaporating, as well as a small chilling effect of the endothermal expansion of the air across a closed or part closed throttle. Then there is Lussac's law to consider when the charge is compressed, AND, heat of compression as a result of the inefficiency of the compressor (work done), AND, heat soak. Anything else?

Any of you clever people bothered about working it out? I for one know how it works, but I am to thick and to lazy to actualy quantify it. Far to complicated

Who cares anyway when you know what the end result will be whether it is a gut feeling, educated guess or both

What we really need is a fluid with a very high specific heat capacity that carries it own oxygen to inject before the blower.

Now that would be beneficial.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Water?

oh hang on

what about N2O

nitromethane?

What the fuck is going on in here?????????

I run a supercharger and I don't care the TB is on the wrong side.
VEMS + 12 PSI + Liquid Intercooler = Small Bore FUN!