intercooler sprayer

[G-E]

crowbar wrote: I agree. Water has just too high an evaporation point. That is why I would suggest another working fluid.

I suppose this is why we don't use water in the cooling system, because 100% alcohol is better obviously....

since the water will not stay on the i/c for very long - any airflow would brush it off - the whole idea of heat soaking the water is stupid, secondly as long as the water is cooler it will keep sucking heat away from the aluminum.... hardly a bad thing is it?

the fact that water can absorb so much heat without evaporating will help remove heat from the i/c not hurt it, the alcohol and co2 are nice and all but you waste their potential to cool if they fly away before absorbing what they can

but hey don't let reality stop you, bumble ahead full speed by all means

[OR-Zman]

GE- makes sense to me.

But what do I know I don't have a Thermo Dynamics Engineering degree, I just get by on the 2 useless degrees I already have and figure that common sense will guide me the rest of the way, OK, toss in some life and car experience and lots of learning on the boards mixed with some actual real world experience.

crowbar- As I have said before, is your intention to aggravate other members or add useful information to this board? Pick your poison. You are getting damn close to the end of my tolerance levels. :evil:

[G-E]

I really don't get offended by insults but I do get annoyed when someone is constantly arguing with what I say but never actually corrects me.... you might have noticed that happening here lately

like I might say X does Y, and instead of a reply like "no actually X does Z and here's how I know..." I get something more like "there you go pissing in the wind" or other useless commentary

and more to the point, this site gets filled up with useless posts that someone has to clean up later to keep the thing on topic and keep it educational

- only state qualified opinions and define the statement as unproven in some way, if you are 100% certain and have evidence then make that known as well, one person's fact could actually be a misinterpretation of events, and conversely any given fact might help someone understand something else

- if you have experience/evidence then recount it in detail including any caveats you can think of, the more we know, the more we can explore the issue further

- when refuting someone's statements, show evidence to the contrary, explain the problem with the premise or theory, insulting or otherwise being negative toward the poster adds nothing to this forum

- when a question is asked regarding information/credibility/related items, whoever can should answer it, ignoring it frustrates the whole process of discussion

[crowbar]

roastin300 wrote: I will agree, a good quality intercooler will do the job and not need intercooler sprayers. If your using CO2 then it might be worth it even with a good intercooler but just sprayin water on it isnt worth it. Me and my buddy did a water sprayer on his intercooler with 3 windsheild washer sprayers with a fuel pump and a pressure switch. We didnt notice any difference in power or detonation threshold so we removed it. You might be better off with water/methanol or alcohol injection to cool the intake charge. However that will only work to a point, it starts robbing power from you at some point

I would agree with this finding.

People are confusing spraying external-water on as a power-adder with spraying water on as a recovery method (scrub heat soaked IC).

The classic confusion between radiators and IC has also popped up (G-E).

The dynamic action of heat rise from a pressure effect is very fast. The method of removing heat through conduction can have some value as the heat effect is being produced.. The heat can be absorbed into the metal structure of the IC rapidly.

The method of removing the heat that has been soaked into the metal to a fluid (air or liquid) is the discussion here. Can it be done while the boost is occuring? This is convection.

I would suggest a smaller IC, with a closed system that sprays alk, and recovers the alk after evap, could do the job of a large bulky IC.

Water could only be used as a 'recovery' system in my opinion. And it is slow.

[G-E]

The classic confusion between radiators and IC has also popped up (G-E).
I'm sorry, I must have mistaken the idea of a finned core removing heat from one medium to another, with the idea of a finned core removing heat from one medium to another

thank you for clarifying that once again, much appreciated

People are confusing spraying external-water on as a power-adder with spraying water on as a recovery method (scrub heat soaked IC).

while we're on the topic, lets read the topic: intercooler sprayer .... now the physics aspect of it, simply anything at or near ambient temperature can only absorb the heat difference between it and the intercooler core, using something like CO2 spray might help just like NO2 as they can be below ambient temperature, and if you spray enough of the stuff on the core, you could potentially get sub-ambient temperature

but like I also said the effect is minimal and the quantity to do so is wasteful, and therefore "scrubbing" the i/c of heat when the air stops moving across it seems to be the better plan, assuming it is sized correctly once the car is in motion you wouldn't need to use fancy external cooling

but I must be wrong, right?

[Jason84NA2T]

crowbar wrote: The method of removing the heat that has been soaked into the metal to a fluid (air or liquid) is the discussion here. Can it be done while the boost is occuring? This is convection.

An intercooler core is generally designed for a "working range" of heat dissipation much like a radiator is. You would not use a radiator designed for a Geo on a 9L truck engine.

That is, one intercooler CAN handle constant boost and will stabilize at a given outlet temperature PROVIDED it was designed to and has enough airflow through the other side of the core to offset the heatsoaking effect.

Yes, the core itself is just a big heatsink not much different than that you would see on most electronic devices except that it is removing heat from air instead of silicon.

Weather or not the intercooler can do this is another story entirely, and is simply a function both of the design and intended use of the core.

1. Take a look at my Isuzu NPR core which is made by tokyo radiator for use on small diesel engines.



I was able to run several back-to-back 1/4 mile passes without ANY heatsoaking issues whatsoever (the core would be cool to the touch after a run) because the tube and fin core was designed with long passages and lots of turbulators, plus a large frontal area ratio.

2. Take a look at my Bell "race" core.



This intercooler IS effectively a very heavy and slow heatsink when compared to the one above. There are far more internal turbulators than there are external, and the thing weighs about 20lbs. This was designed for huge airflow and heat removal for a relatively short period of time, and not intended to have to have the efficiency to stabilize outlet temperatures during extended periods of boost; someone could say it's built more for drag racing than track racing.

Just to clear this up for some people... On to the issue of dropping the core temperature to accomplish a reduction of outlet temperature. Regardless if the core has been heatsoaked or not, all you are doing is trying to reduce the temperature of the assembly as efficiently as possible.

Water works, I won't debate that. The "issue" is it's going to be much slower and drop the temperature a small amount due to it's small evaporative cooling effect. Gasses are going to be your best option here. CO2 is one option because it's fairly inexpensive, but look at the cost/cooling of any compressed gas in the end and how often you will be using it. For it's heat removal ability, nitrous actually works out to be a very cost-effective solution. Now the question is weather to waste a good portion of it by spraying it outside the intercooler, or allow it to have the full effect by spraying it with gas after the intercooler :wink:

[crowbar]

Water would mostly work in a 'recuperative' mode when the IC stops seeing boost. Again, the normal non-boosted air flow into the engine 'cools' the IC internally (the heat gets sucked into the engine) so it may be deceptively 'cooler' unless you actually use some form of temp measurement.

If intercoolers were such great radiators, why not put a big fan on it? If nothing else, it would help recovery.

Car radiators do not see the rapid rise that intercoolers do. In fact, the thermostat is fast enough to work with it. The radiator is meant to work in nearly a steady state type environment.

[Alex86na2t]

crowbar wrote: Water would mostly work in a 'recuperative' mode when the IC stops seeing boost. Again, the normal non-boosted air flow into the engine 'cools' the IC internally (the heat gets sucked into the engine) so it may be deceptively 'cooler' unless you actually use some form of temp measurement.

If intercoolers were such great radiators, why not put a big fan on it? If nothing else, it would help recovery.

Car radiators do not see the rapid rise that intercoolers do. In fact, the thermostat is fast enough to work with it. The radiator is meant to work in nearly a steady state type environment.

Recuperative? why wouldn't it work while you were boosting. The water will absolutly be coldr than the intercooler, coolin the core, and then the core cooling the air. it should work all the time.

Also i intend on combining a co2 sprayer with a water sprayer to take full advantage of the subzero temps of the gas. Maybe add some antifreeze to help keep the water from freezing.

[G-E]

If intercoolers were such great radiators, why not put a big fan on it? If nothing else, it would help recovery.

I've seen it done, and it is an excellent idea wherever you have poor direct airflow, with a fan you could suck air from under the car or mount the i/c parallel to the car if space required....

Recuperative? why wouldn't it work while you were boosting. The water will absolutly be coldr than the intercooler, coolin the core, and then the core cooling the air. it should work all the time.

anything that can absorb and displace heat from the intake charge will obviously help i/c efficiency, water, alcohol, gas..... the question that needs to be asked is the cost vs. benefit, and if cost is high or benefit is marginal how do you improve that?

probably the biggest downside to any consumable cooling solution is exactly that, you run out, you need to keep track of the quantity left, if you're tuned around it then you could have problems if it fails.... if you are using it for auxillary cooling or reducing heatsoak then it isn't so critical

[crowbar]

The reason most manufacturers do not put fans on IC is because there already is an internal fan. By that I mean the natural internal flow of air while the car is not boosting. Once the car quits boosting, the car is drawing ambient (or close enough) air through the IC internals. The IC rapidly gets the heat scrubbed off internally. An exterior fan may help speed this up but it is not commonly seen.

One might even want to have an internal sprayer that assists in this process post-boost. Note that the heat is going directly into the engine. The engine is basically going to see a water saturated intake charge.

As far as an active IC device, one that reduces the size/weight/etc of the traditional IC, I would lean towards something that uses R134 in a closed system method. Again, this is more of a 'dragster' device. One that can keep up with the short term, rapid heat rise that is present during boost. More than likely something that feeds off the existing AC of the car.

Most external solutions are messy to say the least. At most they are recuperative. I suppose dry-ice would work short term. There is also re-usable sub-frozen-gel type products. They require a super-freezer to be 'reset' (much colder than your kitchen unit). But they would be short term also. When in contact with the IC, the IC will rapidly conduct ambient 'heat' into them. If CO2 is cold enough (it did stop the Blob), Then perhaps these 'cold-batteries' could be reset by spraying the whole IC and cold-gel-packs (They would sit on top of the IC in some fashion) by spraying the unit pre-race.

[G-E]

The reason most manufacturers do not put fans on IC is because there already is an internal fan.

I would suggest cost is the greatest reason, as is the fact that most cars didn't come with intercoolers in the first place.... excepting of course smaller non-usdm nissans and all the big diesel trucks

[GotFast?]

Actually wouldn't water be the best substance to spray on an intercooler.

Product Latent Heat of Evaporation
(kJ/kg) (Btu/lb)
Alcohol 896 385
Ammonia 1369 589
Aniline 450 193
Carbon dioxide 574 247
Ether 377 162
Helium 21 9
Hydrogen 461 198
Nitrogen 199 86
Oxygen 214 92
Sulphur 1510 650
Toluene 351 151
Turpentine 293 126
Water 2257 970.4

If you spary an equal mass of any of these substances, water is going to remove the most Btu before evaporation. These are numbers for there boiling points though. So wouldnt spray water at or near is boiling point be the best way to transfer heat out of the intercooler and into the air.

Maybe I'm thinking of this incorrectly as it has been a long time since I have done any sort of thermodynamic studies.

Please feel free to correct me if I am wrong.

[G-E]

yes water is good, but no you don't throw boiling water at it heh

any dense substance has inertia, since heat is motion (as is all energy in a manner), you could think of it like sticking your tongue on a freezing cold flagpole.... eventually you do warm it up but it has so much more inertia than your tongue so you change temp to meet it and not vice versa, hence freeze

any substance you throw on the i/c will have this effect to varying degree, the more dense/massive the substance the more effective it will be absorbing the heat from the aluminum, and let me point out for the slow amongst you, we are actually dealing with very little aluminum, trying to cool down a solid 3"x3" cube of aluminum would be much harder

but you have to ensure that whatever substance used to suck the heat out will either dissipate or get blown off or run of by itself somehow, or all you're doing is adding insulation..... so spraying cold corn syrup would be a bad idea, even if it was sub-zero

and yes water will absorb more heat than other fluids/gases suggested in the thread, and by far it's the cheapest.... I see no reason to play around with the other stuff except for two properties you might want to adjust

1. spray atomization, lighter fluids (alcohol) besides having a lower boiling point usually atomize better, for example when they make minature props to film a dam breaking and water splashing over everything, they use alcohol! ... to atomize water in a similar way requires much higher pressures, and the reason you might want an atomized spray in the first place is more even coverage of the cooling spray on the i/c

2. if you want to go exotic go all the way, compressed gases can be stored at very dense and cold states, releasing very cold gas has two advantages for this application;
- cooling well below the temperature afforded by stored water or other liquids
- causing the atmospheric humidity to condense or even freeze onto the i/c surfaces providing a bit of cooling even after the gas stops spraying

....

take your pick, I suggest water

[crowbar]

Hmmmm. Where to begin?

Maybe some Physics might help.

As far as cooling something with boiling water (water at 212F), It would work very well if the object to be cooled was at a higher temperature. It would hit the very hot object and flash to steam taking away heat from that object. Try misting hot water onto a very hot turbo charger (don't get carried away). You will see this effect. The water will change from a liquid to a gas (steam) in a split second taking away not only heat but also removing itself from the surface. One could 'pulse' a pressurized 'mist' so that it very effectively leaves the surface being cooled 'dry'.


But the related temps and the dynamic rate of change of the intercooler problem needs to be understood. Pressurizing the air beyond a point will raise the temperature up quickly. The pressurized 'air' is actually a very thin fluid. It behaves according to fluid dynamics.

The intercooler is desired to remove the heat from the intake charge. Typically its desired to reduce the intake charge down to 100 degrees F. But it must do this to a moving column of pressurized air. This is the engineering problem. The conduction of heat from the air to the metal has to be done very fast. The convection of heat from the metal to the exterior ambient air must likewise be fast.

The problem is that the conduction is better than the convection. The heat can get into the intercooler faster than it can be removed. Its a dynamic rapid heat rise that should not be confused with the nearly steady state automobile radiator.

The last time I checked at the beach, the oceans warmed up slowly. The 'inertia' that is being seen here is the very slow heating of water. But once the water warms up, it acts like a heat 'battery' and retains that heat (like the gulf of mexico).

So when someone says 'water absorbs more heat than other fluids, it must be understood that the rate at which it absorbs heat is critical.

Product Latent Heat of Evaporation
(kJ/kg) (Btu/lb)
Alcohol 896 385
Water 2257 970.4

note: all this means is that it takes more energy per mass to change water to 'steam' (gas) than it does to change alcohol from a liquid to a gas. Also note that alcohol does this at a lower temperature! If one wanted to mist 'hot' alcohol (this is dangerous indoors) onto the intercooler so that it 'flashed' it would be at about 150 deg F (pre-heated by some means). Again, thats too high but you would have a means to limit or brake a runaway heat condition in the intercooler. But we want a lower temp.

Ideally we want something that 'boils' at a low temp. Like R134. Here you would have to build a closed vessel system. Spraying R134 externally is expensive and sloppy. You would need a means by which it is pressurized, and then recovered.

Another scheme is to inject very cold gasoline before the intercooler. Ideally, the air-fuel charge takes this into account. The gasoline will 'soak' the heat up as it changes from a liquid to a true physical gas. I would want the spray to hit the mass of the intercooler at its thickest part. I would suggest using dry ice as a means to super-cool the gasoline.

Some interesting info.

http://www.eere.energy.gov/afdc/pdfs/fueltable.pdf

[G-E]

evaporation isn't the great event you think it is, evaporating means changing state yes, but it also means leaving

once the cooling medium leaves it no longer cools, so really what you want is something to hang around absorbing as much heat as it can and leaving while it's still reasonably cool but not so soon as to be wasteful unless you have limitless supply

so besides most of your post being more or less arguably correct, I see no point in using a medium that evaporates extremely quickly on contact, you just don't get the btu per quantity you would with water

and if you're going to supercool something like gas to what? -20C ? why bother, why not cool water to about +4C, sure dry ice is fine or use the a/c system, if you're going to pre-cool the medium you can make water similarly effective to a compressed gas spray, but much cheaper and readily available

now lets consider water "hanging around", lets consider when I suggested using it, AFTER the car comes out of boost and slows down, you use water to replace the effect of high speed airflow over the core, and it won't take much to drop the core temps back down to the water temp.... sure it might stay wet for a few minutes, but once the car is in motion again the air will blow it away

oh yea, and water doesn't have to boil to evaporate, nor does any low boiling point liquid