While in my auto tech. performance class, I reciently heard of a different method used for intercooling, and thats the water radiated (water to air)intercooler, and I am a little bit confused... does it run off the cooling system, and if so, wouldnt it make the incoming compressed air hot?
I just want clarifiaction and how this method is used and how it benefits...
Originally Posted by Pen2_the_penguin
While in my auto tech. performance class, I reciently heard of a different method used for intercooling, and thats the water radiated (water to air)intercooler, and I am a little bit confused... does it run off the cooling system, and if so, wouldnt it make the incoming compressed air hot?
I just want clarifiaction and how this method is used and how it benefits...
A proper water\air intercooler should be a separate system from your engine cooling system. Understand that the idea of an intercooler is to cool down the compressed air in your charge pipes to increase the Oxygen to the cylinders. Typically if one can achieve close to ambient temperatures it's a win. The typical engine cooling system runs between 180-210 degrees. That means the charge could be cooled no lower that this by an w\a intercooler if it was plumbed in to the engine cooling system.
Water\air needs separate heat exchangers, pump, and lines from engine cooling system.
here is a nice FAQ on intercoolers both W/A and A/A.
pages/techFAQ.html
Air to water systems are used for the packaging advantage. The intercooler itself can be smaller and located where it is convenient. The air to air intercooler is nearly always located in the nose of the car and the intake pipes routed to there and back to the engine.
Some OE air to water systems use the radiator water. Yes, this can heat the intake charge in some conditions. However, if the compressor discharge is hot enough (supercharger under boost) even the radiator fluid is 'coolant'. And yes, many OE setup have such high compress discharge temperature. Various GM and Jaguar and other OE systems have employed this scheme.
With a small increase in complexity, the water in the air/water intercooler may be provided with its own cooling system and radiator.
To expand on the Bell write up.
Air to air is one step, hot compressed air is cooled with ambient air. The higher the temperature differential, the more heat can be extracted. You need to double the area of a 70% efficient A/A intercooler to get to 90%, because the second half is seeing air that is already pretty cool.
For the front mounted radiator to cool the water in a W/A intercooler, the water must be hot. If the water is hot, it isn't cooling the intake air much. There is a temperature where the heat being extracted from the intake is being extracted from the radiator, and a large radiator will lower that temperature. But to reduce the temperature near ambient would require a huge radiator.
Final analysis, if you drag race or boost on a very low duty cycle (15 seconds every 5 minutes), W/A is OK. Any extended time on boost - auto cross or the like, use A/A.
Originally Posted by Lance Schall
Air to water systems are used for the packaging advantage. The intercooler itself can be smaller and located where it is convenient. The air to air intercooler is nearly always located in the nose of the car and the intake pipes routed to there and back to the engine.
Some OE air to water systems use the radiator water. Yes, this can heat the intake charge in some conditions. However, if the compressor discharge is hot enough (supercharger under boost) even the radiator fluid is 'coolant'. And yes, many OE setup have such high compress discharge temperature. Various GM and Jaguar and other OE systems have employed this scheme.
With a small increase in complexity, the water in the air/water intercooler may be provided with its own cooling system and radiator.
One day I will measure the temperature of the water exiting the radiator. I expect it below the engine water temp (180 - 200), but I would be surprised if it was below 150, even with a 55mm radiator.
Yes, and the supercharger discharge can be 300F, so 150F is a coolant. The OE market has demonstrated that this scheme can be used and is effective from an engineering and cost perspective.
Lance, Lance,,,,, enjuneers NO, Accountants YES.
We need an open season....... naaah forget it.
Corky
My Saturn Ion Redline (Factory supercharged with a M62) uses a Water to air heat exchanger. The heat exchanger coolant is on it's own circuit separate from the engine coolant. It has it's own pump, hoses,ect.
The coolant is circulated though a quot;laminovaquot; coil in the intake manifold, though hoses to a nose mounted heat exchanger (i.e. radiator). The system on my car has no external expansion tank or resiouvor. It's a closed loop system. There is an option to plumb an external tank into the setup. Some guys cram ice into these tanks on race day to keep their intake charge temps down.
Originally Posted by Corky Bell
Lance, Lance,,,,, enjuneers NO, Accountants YES.
We need an open season....... naaah forget it.
Corky
Ha ha! Yeah, I know what you're saying. I'll give the engineer credit for coming up with something that works when handed a list of requirements by marketing, cost target from the accountant, a schedule from his manager....etc
Personally, not be constrained so much by cost, I'd look at an independent cooling system and consider the idea of finding a working fluid for this coolant that phase changes at a temperature that matches the intercooler discharge target...
Originally Posted by Lance Schall
Ha ha! Yeah, I know what you're saying. I'll give the engineer credit for coming up with something that works when handed a list of requirements by marketing, cost target from the accountant, a schedule from his manager....etc
Personally, not be constrained so much by cost, I'd look at an independent cooling system and consider the idea of finding a working fluid for this coolant that phase changes at a temperature that matches the intercooler discharge target...
Liquid to gas, a range of liquids under the right pressure (or vacuum) - solid to liquid, wax, but it doesn't flow very easily.
You will still have low temperature differential between the gas and ambient. You could compress the gas to make it hot so it would cool better - maybe use freon, oh wait, that's an air conditioning....
Thank you all for quickly clarifying that to me, and from what I gather, if I am not going to run extreme amounts of hp, I should just stick with the regular air-air intercooler. But overall, its good effective system under its own pump, heat extractor, and cooling fluid, right?
Originally Posted by Pen2_the_penguin
Thank you all for quickly clarifying that to me, and from what I gather, if I am not going to run extreme amounts of hp, I should just stick with the regular air-air intercooler. But overall, its good effective system under its own pump, heat extractor, and cooling fluid, right?
It's good for short burst like drag racing not sure I'd rely on it for a road race, hill climb or the likes. Other opinions my vary.
Many things we use everyday are here because some jokers that are not restricted by the same old thinking box (why does Lance come to mind?) are busy pointing the way to some idea that might work better.
The problem then becomes; what is the best thing I can utilize right now?
The answer is what works today..... air/air, other than defined special apps.
Jokers like Lance will one day suggest a possibility that flunkies like me can run with.
What bugs the hell out of me is that I did not get blessed with the quot;idea partquot; gene to accompany the moderate ability to make something gene.
So, do we need Lance type jokers? Yeah, we do. Just hope they keep at it.
Corky
6.5 bhp weed eater, quot;downquot; for hop quot;upquot;
I am one of the guys who strongly believe in water to air intercooling as long as I find a way to keep water temperatures stable on day to day basis. The first thing I will do is add a fan and water temp gauge to the heat exchanger to monitor water temperatures when the car is on and off boost. Water to air intercooling sparks my curiosity and it is more expensive to build than air to air intercooling. . and knowing myself I think I'll give a try.
Hyper; Go for it. We all might learn something.
Please be aware that you have chosen a path that lots of us have pounded on for decades.
Please make sure you define the goals, as that determines the approach.
Corky
Proprietor of the 12 bhp, but blown up, weed eater.
( it was really fun for an intense 20 seconds)
this is a topic in which the only way to find hidden answers is by throwing money into a concept just to experiment, just to see if it could work. What I have in mind should quot;aidquot; in keeping water temperatures stable but as far keeping the water from boiling in a track car I highly doubt. That's why I refrain myself from making comments until I study other concepts that make more sense to me. There are other less expensive, more effective avenues to intercooling than Water to Air assuming this is for a daily driven car.
Most of my beleifs in what makes an 'ideal' turbo setup come from the turbo F1 cars from the 80's and modern rally cars. In both those cases you see almost exclusivley air/air intercoolers.
That, coupled with my experiences working with turbo hondas make me thing that air/air is the way to go. Ive always gotten a kick of feeling the temperature difference across the face of an air/air intercooler, even on a 450 hp gt35R H22 powered civic the dowstream end of the intercooler is usually cool to the touch after making a dyno pull.
Originally Posted by Corky Bell
Corky
Proprietor of the 12 bhp, but blown up, weed eater.
( it was really fun for an intense 20 seconds)
Let me guess, it was a 4cc engine with 72lbs of boost. Was the turbo bigger than the engine?
Originally Posted by Hyper
this is a topic in which the only way to find hidden answers is by throwing money into a concept just to experiment, just to see if it could work. What I have in mind should quot;aidquot; in keeping water temperatures stable but as far keeping the water from boiling in a track car I highly doubt. That's why I refrain myself from making comments until I study other concepts that make more sense to me. There are other less expensive, more effective avenues to intercooling than Water to Air assuming this is for a daily driven car.
Hyper,
This has been done and discussed ad nauseam.
If you already have the parts or have some space constraints then go for it, but there really isn't much to prove here one way or the other.
I have run A/W intercooling for 6 years mainly because I was supercharged and kept my old parts when I went turbo, it's was easy to do the plumbing, and my car is a daily driver, real daily driver, as in 2 hrs. commute each way and half of that is stop amp; go city traffic in South Florida. My needs are more A/C cooling than intercooling, so blocking the mouth of the bumper with an big A/A intercooler is not really practical for me.
If my car was a circuit track car, Sunday driver, mostly highway driven, or lived in a cooler climate, it would we A/A intercooled for it's efficiency and simplicity.
Later
Originally Posted by MiaMiata
Hyper,
This has been done and discussed ad nauseam.
If you already have the parts or have some space constraints then go for it, but there really isn't much to prove here one way or the other.
I have run A/W intercooling for 6 years mainly because I was supercharged and kept my old parts when I went turbo, it's was easy to do the plumbing, and my car is a daily driver, real daily driver, as in 2 hrs. commute each way and half of that is stop amp; go city traffic in South Florida. My needs are more A/C cooling than intercooling, so blocking the mouth of the bumper with an big A/A intercooler is not really practical for me.
If my car was a circuit track car, Sunday driver, mostly highway driven, or lived in a cooler climate, it would we A/A intercooled for it's efficiency and simplicity.
Later
I love the concept thanks to you, then I saw Big Gulp's car and I inherited his parts to do mine. but there are other avenues to design a more efficient W/A set up, I just need to experiment, hold on..
Theres not much to expirement with, Air/Air is thermodynamically more efficient, It will always have higher potential for efficiency.
Im not saying it cant work, or work well, but if your intentions are to make a air/water intercooler more efficient than awell set up air/air intercooler its just not going to happen.
P.S. An Icebox is not an water/air intercooler, its an icebox. haha
Originally Posted by 31337
Theres not much to expirement with, Air/Air is thermodynamically more efficient, It will always have higher potential for efficiency.
Im not saying it cant work, or work well, but if your intentions are to make a air/water intercooler more efficient than awell set up air/air intercooler its just not going to happen.
P.S. An Icebox is not an water/air intercooler, its an icebox. haha
who said I want to imitate the same W/A concept? I like the concept but there are other avenues to experiment not just with water. The are set ups that cool the air by spraying C02, Mercedes Turbos the 600hp+ quot;Black Linequot; cool the turbos with A/C.
Find me an schematic diagrahm of one those Mercedes cars and everything is possible.
Steve, yeah, I had to mount the turbo on a wheel barrow.
Have you ever heard a weed scream? Well, I have.
There are many things to be invented yet. If a better IC can be had, we would all benefit.
If you think you have the key, go for it. Please pay attention to one thing, however, the principles of heat transfer and thermodynamics are not going to be the inventor's friend. Finding a better way within those principles is always possible and my hat's off to the genius that does it.
Corky
Originally Posted by Corky Bell
Steve, yeah, I had to mount the turbo on a wheel barrow.
Have you ever heard a weed scream? Well, I have.
There are many things to be invented yet. If a better IC can be had, we would all benefit.
If you think you have the key, go for it. Please pay attention to one thing, however, the principles of heat transfer and thermodynamics are not going to be the inventor's friend. Finding a better way within those principles is always possible and my hat's off to the genius that does it.
Corky
How open are you to new ideas and concepts? The problem is that new ideas are not taken well by others when they are experimented for the first time. I know I can cool the water by running a line through the A/C, I just don't know how much cooling effect this will do to the water but I have always been curious on that.. Care to give your opinion Mr. Bell?
Thinking as a non-engineer and a non accountant, how about a second belt driven 'fan' that is designed for cfm, feeding a countercurrent heat exchanger in the w/a circuit?
Or maybe this is the one time that the electric motor from a vaccuum cleaner / leaf blower might actually be useful in an automotive application?  |
Post at 2-7 04:28 AM
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