What parts do I need to make a good reliable water/air IC system? Please list them. What size core is the best to mount where stock air box use to sit in an EG(92-95civic)chassis?

 

If you e-mail spearco, they will send you a free catalog. Ask them alot of questions, winners use spearco, hehehe.... I don't have a spearco, by the way, but am persuaded to get an air/water IC to reduce the 10 feet of piping in the prelude turbo kit...

 

Im looking to get a liquid to air IC also. Let me know when you find out.

art

 

I'll do that fellas...

 

I have the spearco one... i believe the ports are 2.25 or 2.5 inches.... ~ 400 bux... i dont have the exact core size on me... but it works well..

Not very big at all... and fits nicely where my old airbox used to sit...

 

the water-air ones are supposed to be more effective than the regular air convection IC's right?

I can think of several ways to cool down air that goes to the engine, my other question, relating to this, would be: If the device that cools the air uses power, (like speakers do) would it be taking much power away from the engine? And say it lowered the intake temp to 60F and the IC temp to 90-95F, then would this increase in power be noticeable? Or would the couple hundred (75-225) watts of cooling power and extra 20-40lbs of equipment (and the space it occupies) be wasteful?

I say this because I'm great with thermodynamics...I've already planned some things to increase the cooling efficiency of the engine without the extra power consumption, but this, this will take power because it is lowering below ambient temp...so I was just wondering...this could make a true cold air intake

 

Oh, in case my real question got muddled in my long post, it is really this:

Would the power consumption of below ambient cooling diminish power from the engine enough such that it's benefits are rendered negligible or detrimental (not beneficial i guess)?

Refer to the temps posted in my previous post for "how much cooler"

 

I understand what you mean.... but the only negative draw of power is that pulled from the water pump which is electric..... Although it is usually of high power... when you're booted around, your alternator (even with underdrive pulleys) is putting out much extra juice... so i can't see there being a problem as you've shown concern....

 

air/water IC's are more efficient at the track but not really for daily driving. Unless you stop at every 7/11 and fill the thing with ice water. I think the water would actually get hotter and not work as well as an air/air IC. Because once the water is warmedup there's nothing to cool it down. Unless of course you put a small radiator inline but then the water will be only as cold as the ambient temperature so might as well just use an air/air. But for all out track racing it is all about water/air.

 

And that's what they do. The end result is that heat exchange gets split into two parts: the intake air warms the water, the water radiates waste heat in a separate (much smaller than air-air) radiator.

For cooling to ambient, air-water is a clear winner on paper. For one thing, the 14-1 improvement in heat soak is huge. A clear example is when I turn on my gas stove at home: the air over the burner is immediately really hot, a pot full of water just laughs (of course, the _pot_ gets hot but the water doesn't even twitch). Besides, you're dealing with smaller hoses, littler radiators, etc.

Cooling to below ambient takes work: one way the air-water guys make it happen is to fill the reservoir with ice. When the ice is gone, your ability to cool below ambient is gone but you still have the existing system.

Now, you need to understand that I don't have either kind of system. The physics is pretty clear and I like the look of the air-water systems much more. All that air-air piping is just so tacky doncha know....

--
DoctorBob

 

Archmage, unless the pump is pulling 10-20 amps, there actually isn't much strain on the electrical system. Are you an engineer of some sorts? Do you have a turbo? I have an idea....in a minute.

A very good thing about the air/water IC (I may have read it in this board), is the potential for cooling when the water is at ambient due to being cooled by the little radiator thing in front. If you have a good amount of stored water (2-4 gal), it will take alot more energy to heat it up from normal driving to hard acceleration and be efficient for longer periods of time compared to an equal capacity air/air IC. When the water does actually reach the high temps from the compressor (which it shouldn't because of the radiator), it will be less efficient than the air/air IC.

Now for my idea...what if we had a tiny radiator (small enough to apply @ 4000btus of heat)placed after the air conditioning evap coil to cool the water during regular driving and store it in an insulated reservoir. For quick freeway spurts, you're getting AT LEAST ambient temperature charge into the engine while the ac is off. I know we don't race with the AC on (for those of us who have ACs), but the water will be cold enough with alot of potential for cooling that 250 degree turbo discharge.


[Modified by G, 3:46 PM 8/9/2001]

 

I'm not the type of engineer you would expect, I'm an EE and I'm good with programming as well...that's about it...

But on top of that, I may as well have a degree in thermodynamics because I use nitrogen compressors, and R-134a or R-22 refrigerant to cool down my processors and video cards (so that they will perform better...a 1Ghz cpu at 1.93Ghz is an example)

So your cooling idea, is basically very similar to mine....but to design the cooling system, I'd have to take a look at "blueprints" for the air-water and air-air IC's...

But below ambient air is very possible because the electrical system isn't that strained...hehe... (I have an extra lightweight 1HP R-22 compressor...makes for -10C reservoir temps in your idea...(except not using the AC...just using this unit)

I'll go look for the designs and then post an idea...

 

actually, to save on weight and space, I think I won't even use compressors..I just had a different thought...I think I can implement that cooling for under 10 pounds at the same power requirement...it may cool a little worse though, but it's a good compromise for the weight and the space..

Anyone ever heard of peltiers? (thermoelectric devices) Once an electrical current is sent through these things, one side heats up very hot, and the other gets very cold..if you keep the hot side to within 10 degrees of ambient, the cold side will be more than 10degrees below zero in no time...The water can be run through a chiller using aluminum waterblock with the hot-side being cooled through a ducted heatercore and evaporative cooler...you'd have to refill it about every week though..

Now I shall REALLY go check if this will work...how many watts of heat are we talking about to expel here? about 300-500 maybe to get to ambient?

EDIT: we could also try to save on space by replacing the AC unit with a much more powerful one such that it cools the IC first, and then goes to the evaporator to cool the car...if powerful enough, that would work...seems kinda doubtful though...


[Modified by archmage, 5:26 PM 8/9/2001]

 

I would think, at the most, 250 gegrees F at 1000cfm. I am unsure of the conversion, but if I can find it.... Actually, 10 psi usually gains about 300-400hp. Find out the cfm to hp ratio to get the cfm and cool that amount of air to @ 80 deg F. I will research....BRB.......

As for the peltier, I have read about it in my 1980s Air conditioning book, a bit out-dated. I think the Toyota previa van has a small refrig that uses it....Hmmmm...

 

they are outdated, for refrigeration, but they are compact as hell, so the weight involved would be zilch...Most people would probably want to keep their air-conditioning (me for one) on a street car...so this would be an alternative..

I'll give you some links to some pictures of these types of chillers being implemented to show you JUST HOW EFFECTIVE THEY CAN BE when implemented correctly...I'll have to get my digicam, or go search for them...

Unfortunately, I have to goto class right now...so maybe in around 6.5 hours I'll be back..

Later

 

I have been thinking that instead of having the drain from the evaporator running onto the pavement that you direct it to a more useful purpose. After all, it is chilled water albeit a small amount depending on the humidity. Maybe have it run into the IC radiator you are talking about or just directly on an air IC.

 

Guy man,

Those Peltier units (or whatever they are called)... I've read about them... quite an awesome idea.... but just wondering, since you're into all the calculations.... what about sticking them all over the aluminum water IC itself? the aluminum would cool down to below freezing and really help chill the water.... Perhaps sticking them onto the mini rad/cooling core we use would be best.. that way there is a movement of air around them to keep the hot side closer to ambient...

What'chu think? Would use a little power... but shouldnt be too much... Probbaly would work great..

 

Ok, here are the pics..Actually, the link to the pics I suppose, I dunno...you'll see...I know a guy who setup this peltier chiller, he uses a normal small radiator to cool the hot side...with this, he achieves anti-freeze temps of -18C and actually lower than that if you ask..more like -22C when he found new techniques to fully insulate and then switched from aluminum to copper...His final cpu temp (via another peltier) was under -50C...
http://www.frostyfox.com/pic/new63.jpg</a> http://www.frostyfox.com/pic/new66.jpg http://www.frostyfox.com/pic/new64.jpg <A HREF="http://www.frostyfox.com/pic/new65.jpg" TARGET="_blank">http://www.frostyfox.com/pic/new65.jpg

Edit: I forgot to mention, that was while running a heatload of a 72w peltier and a celeron CPU (a little under 100watts)...I don't know what the website says, but that's what he said..

The first two pics are right when the peltiers were hooked up...The second two were about 24 and 29 minutes after (but if you visit the site, it says 30 min)...With this, he got his celeron 1 to 735 I think, possibly higher..I forgot since it was so long ago...I run a T-bird 1Ghz at well over 1.9Ghz if you're wondering (no peltiers though)

THink of the cold side as the inline radiator, that's how this thing would work...The waterblocks for this application will be much bigger, and have slightly larger internal pathways (but still use aluminum to cut down on cost and weight (copper is the better conductor of heat))...What we really want to do is expose surface area to the cold water for as long as possible, 6-7 seconds will make for -20C temps even if the heatload is something like 550watts..the water is constantly being made cold, so the total capacity of the peltiers is not going to be the capacity of the cooling...I had a 52watt peltier cool down a 120watt heatload's water to ambient temperature...

About cooling the intercooler directly, it would be hard to spread the "cold" if you get what I'm driving at...If you could submerge the IC in colder water, then the heat-transfer would be very effective...but then this would add much more weight than this peltier solution, and this peltier solution may work pretty well...

Ok, now that it is out there, I will try it eventually...but not in the near future...I'd rather get the essentials first..this is just an idea I had...whatever...


[Modified by archmage, 6:11 PM 8/10/2001]

 

Mage, for being a whiz at thermodynamics you're either not thinking this one through or you don't have much experience in peltier design. The problem is everyone looks at a TEC and feels the cold side and says "damn, that's cold!" and they're spectacular when you're using one to cool something small with a relatively low heat output, like a CPU, where you can put a heatsink on the hot side with a fan to give you a heatsink area significantly larger than the object you're cooling. Problem is, as the amount of HEAT you're trying to dissipate increases, the temperature difference across the peltier decreases... so if you're at the max heat capacity of the peltier, both sides are the exact same temperature.

Now let's take a quick look at the amount of heat you're actually pulling out of charge air. I'm going to be conservative and say it's been heated to 180 F by the turbo, and you're cooling it to 70 F somewhere near ambient. Your engine is consuming around 32 lbs/min of air at WOT, which means your intercooler has to dissipate just under 8000 BTU/min which translates to 136000 watts. A little more heat than you're used to dealing with coming off your CPU or video card.

When you come up with a way to do 136000 watts worth of cooling with TECs, you can come back and let me know. I assume it's going to involve a trailer to tow the large generator around to power them, and the entire surface of your car covered with finned heatsinks. Granted you can gradually cool a reserve tank of water, but I don't think people understand the sheer quantities of heat we're dealing with here; you may manage to cool a tank of water below ambient over an extended period of time, so that will keep your intake cool for several seconds of full boost, but then you're going to have to wait another hour to get the water that cold again. TECs are just about the LEAST efficent way you can cool a large thermal load; they produce about twice as much heat as they remove. An evaporation cycle refrigeration system would work but again, the amount of heat you're trying to manage would take a very large compressor, and a correspondingly large condenser, fan, etc. Figure your car's AC is designed to cool maybe 50 cubic feet per per minute to a 40 degree temperature drop... how big you think the AC system would be to cool 500 CFM to a 100 degree pressure drop?

1st law of thermodynamics - you can never win.
2nd law of thermodynamics - you can't even break even.

 

I was wondering what the heatload was, now that I know, I know that this is not feasible...

Thanks...Just a regular old intercooler should do fine I suppose...I'll try my idea anyway though....because some guy said that they use a separate radiator in order to cool the water in the IC...I assumed that my peltier system would be able to handle the heatload that the radiator could handle..

Oh well...another idea shot down...yeah....

 

the radiator , that is used to transfer the heat from the water to the surrounding air isnt going to be as good as a FMIC because, the water itself is gonna take a long time to release all it's heat to achieve equilibrium with the ambient air. It isnt like a sudden change, it's going to take a while, to finally get the water temp down if it's significantly heated up, and as we know about reactions and what not, the larger the temp difference the faster the rush towards equi. so, if you can slap on a cooler to the oilcooler/radiator thingy, that would help...But lets not forget, like mentioned above with the laws of thermodynamics, energy is neither created nor destroyed. So that heat is gonna go somewhere.. and the secondlaw of thermodynamics, you can never win.
The peltier system i would imagine would be the same idea as slapping the A/c unit to chill the water, which we have said doesnt work.
But to use it to assist the radiator, perhasp that will be more beneficial, to speed up stabalization of fluid temp post boosting session without the use of ice.