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Ive been getting annoyed trying to find a radiator for my air-water system, and was trying to find some sort of way to say cool a resevoir of the water rather than to have it run through a radiator... I asked around, and got the idea of using Peltiers for it (here is what they are if you dont know, they are generally used for cooling CPU's though: http://www.dansdata.com/pelt.htm )

Anyway, I was just curious if anyone thought it might work... Run a couple Peltiers with heat sinks next to a water resevoir and a switch inside the car to turn them on or off (and maybe a temp sensor to keep track of the water temp).

The problems seem to be that Peltiers are not that durable, and I cant find any info about using them to cool down anything other than CPU's (they are used for other appliances like electric coolers and such and have been around for awhile) and have no idea if they can even effect the temp of the air-water systems water...

Wow I just typed a huge reply to this, but then realized that most of what I was typing you already knew anyway, The only problems I can see with using a pelt setup would bethat it'd be just as hard, if not harder, to get rid of the heat w/out a radiator as it would to try and find a rad that would work without a pelt, the other thing is pelts use a hell of a lot of energy. As far as wether or not they can cool well enough, there's a number of cpu's running below 0 C while using a water cooled peltier system. As a comparison, most cpu's run from 20C-50C depending on the brand/cooling setup. Also most pelt's ahve a max deltaT of 60-70 deg f

So you are saying that I would need something other than heat sinks to keep the hot side cool...

at least a good fan or a smaller cooling setup, much like the watercooled units in pc's. Which consist of a block, pump and radiator (the 78 chevelle heater core is commonly used as a radiator in watercooled rigs). If you only had heatsinks it'll just keep the air around it hot until it is removed somehow, which would inturn heatup the water again.

Yeah, I agree that you'd still have to deal with the problem of removing heat.

You have to remember that peltier units are basically heat pumps -- they transfer heat from the cold side to the hot side. So, once the heat is on the hot side you have to get rid of it just as you would have to get rid of any other heat. This could potentially be done with some phat heat sinks right under the hood scoop; I don't know if you'd get enough air that way or not.

I was thinking of a peltier-based intercooler a while ago, too. My idea was to have the cold sides attached to some big complex heat sinks sticking into the intake charge which would snake around to get it multiple times. Then, you'd run water over the hot sides running to a front-mounted radiator. Basically that would be equivalent to an AWIC but with even higher transfer because of the active elements.

When peltiers are used to cool CPU they are often acompanied by water cooling of the hot side. The problem is that the hot side has more energy than the cold it produced, so you back in the same predicament. If you had some source of air flow over the unit and a large surface area it could definatly help but you would need a fairly large one, the amount of water you are cooling is massive compared to a cpu.

By the time you spent all the money getting it to work you could have upgraded your AW setup.

I dont have a hoodscoop, thus thats why im going with the air-water system.

As for the heat disipation, I would run a switch to inside the car for the peltiers, and say a temp gauge as well for the water. That way, I could turn them on, cool down the water, and shut it back off. But ya, it is just an idea... The mention of running a whole seperate water cooling system, or extra fans would just not be worth it.

I kinda mocked up a funky pick to show location and such: http://community.webshots.com/photo/112 ... 0205msUmwJ

However, if I were to do this, i'd probably run like seperations in the water resevoir, so that the water would seperate and flow past the cool area better to cool down the water more efficiently, as well as have the resevoir made of something like aluminum so that it would be able to cool down on a larger scale.

I was going through searches last night about peltiers, and I DID find out that they are used to cool water fountains as well as under-sink water systems, but the units I found were rather large and bulky, and probably wouldnt cool enough water anyway. To the idea of using peltiers to cool water is not new.

I still dont think it would work. You are putting the heat sink in an area that gets near zero air flow.

ciper wrote:I still dont think it would work. You are putting the heat sink in an area that gets near zero air flow.

Granted, so fans would probably be neccesary at the least, plus perhaps some vents routed to that area from other areas...

Im thinking more like 2 peltiers, and 6 heat sinks connected like a 6 pack to cool them better, mounted on the side of the resevoir... With maybe a fan or two to blow air from the front to back (IE front of the car to the back)

Im almost curious enough to just buy one of the peltiers and wire it up to a 2liter bottle or something and test it with a thermometer to see if it cools it much...

Honestly this isn't a very good idea. Well it is, but to be done efficiently it's going to be more complex and probably cost more than just finding a radiator that works. You HAVE to have good cooling on the hot side of the peltier, it produces a LOT of heat. It also drains a lot of energy. The locqation you are looking at isn't a real good place to put it. What you could do is try to put the 22b vents in your hood, right above that area, and place the peltier as close a possible with a heatsink ontop of that with a 120mm ys-tech on top of that, blowing straight out. Even then I dunno how well it'll cool it. Another thing you could do is run the water tubes all the way to the rear and have the pelt system back there, dunno where you could mount it.

You should look into the water cooling forum on www.amdforums.com and ask this question. You'll get a better response, but suffice to say it wont be easy or cheap.

Ok, so I was at work today, and saw one of those car-electric coolers... It has this section, the power section, kinda screwed onto the side of the cooler. Its all built in together, with the peltier, a heat sink on top, and a fan above it, with a temp sensor to help maintain a ~40 degree temp in the cooler as well... It seemed about perfect, im about to buy one to test it out with water temps and such. (under $30, and i can return it) It also had operating specs on the box. Interesting stuff.

Check the wattage. The power draw is nearly the same as the heat removed. It wouldnt be hard for us to figure out how large of a peltier is needed but I doubt these tiny ones can make any difference.

I thought peltier junctions radiated more heat than the electrical power they consume.

Sorry, meant to say "heat removed"

Ill double check the wattage, but it was rather close to the "aftermarket" peltiers ive seen on those websites...

Interesting related story http://www.csmonitor.com/2004/0206/p14s01-stct.html

ciper wrote:Check the wattage. The power draw is nearly the same as the heat removed. It wouldnt be hard for us to figure out how large of a peltier is needed but I doubt these tiny ones can make any difference.

Ok, the ones on that cooler were 36 watts.