An Intake Temp Cooling Idea

[Cro]

Another quick fix that I've seen used to cool the intercooler is spraying it with nitrous for a few seconds before a run. I'm not sure how expensive this process would be though.

<{POST_SNAPBACK}>

you can use almost any compressed gas to do this

cro, the problem I would see with using the peltiers on the cold air intakes is that the air is still going to pass thrue the turbo which is going to heat it up again alot more efficiently.

<{POST_SNAPBACK}>

hmm too true.

I haven't really looked at the way the piping goes, but I assume after it goes through the turbo it goes through the intercooler.

Maybe cool the pipe between the two?

[Macktheknife]

In short, it just wont work.

The total amount of "Refrigeration" available is negligable compared to the total amount of heat removed from the intercooler under normal operation. Even if you used 50 of them.

Far more to be gained from an increase in size of the IC or, for short bursts, a simple water spray directly on to the IC.

[Guest]

I hear NOS may lower you intake temp and at no loss to you alternater, this is a good post but didn't anyone see the NX IC cooling kits? Carbon dioxide bottle with jets onto your IC and a cooling severe in your intake and a fuel rail with a inlet for Carbon dioxide.

Never heard of this type of set up, flick open a rice mag when you doing the weekly coles misson. Who know if they work?

[mickq]

Three things come to mind when reading that (and I read that myself a few days ago):

1) He doesnt know what he is talking about as he says an 80w one is a powerful one - even the first ones I located for sale cope with 350w.

2) The cooling power he mentioned related to the B4 IC is not the same as power consumption. You can check that for yourself on any airconditioner. As an example they may say it has 6.5kw cooling power, but if you read what the aircon actually consumes, its only 2500w. Dont confuse cooling power with power consumption....something the guy who wrote that obviously has done.

3) Im sure a world class rally car with a massive budget isnt using them for fun....

An extract from an article I found

It frequently crops up in web discussion groups: why can’t Peltier coolers be used to build an intercooler? It seems reasonable enough: Peltier coolers are designed to work off car-type voltages, in recent times their prices have been dropping fast, and they do what you want an intercooler to do – remove heat. (See the breakout for more on these fascinating devices.)

But the short answer regarding Peltier intercoolers is that with the current level of Peltier technology, it’s not going to happen. A powerful Peltier device like this one is rated at 80 watts of electrical power. Wile the relationship between thermal heat movement and electrical input power is not 1:1,  the power rating of a turbo car intercooler (eg the B4 Subaru at 13.4 kilowatts) is so much higher that you’d need something like 15 Peltiers to do the same job – and that’s ignoring the very real problems of the actual heat exchange process and the power consumption from the battery. It’s certainly possible that one day intercooling will head in this direction, but so far it’s not been viable.

<{POST_SNAPBACK}>

[mickq]

On a hot day, at speed I dont think the wind would be heating it up - it would be cooling it down as it draws heat away from the IC. IC's are designed to make good use of airflow, which is why they are placed where they are.

But I agree with the overall logic - the ideal thing would be to encase a bunch of IC tubes in a freezing cold esky like environment.....so cold that air isnt needed to remove the heat.

Personally...if I were to use peltiers as a means of cooling I would be removing the intercooler from the front of the car and relocating it out of any direct airflow...encasing the unit in an insulated case or somthing similar.  This would aid in reducing the thermal losses due to the large amount of unwanted air passing over the intercooler and warming it up.  The increased efficiency by removing the external heating souorce(wind) would mean that you could lower the required voltage...making their use a more viable proposition.

<{POST_SNAPBACK}>

[mickq]

I think the massive volumes of air that travel through the intercooler is that great that you would need that many of these things that 240volts would be required.

Good in theory but in today’s world not even close enough to cope with the volume of air that it would have to deal with.

<{POST_SNAPBACK}>

I cant see how the volume of air is such that you think it wouldnt have its temp lowered if it passes through a freezing cold area.

Think of it - even if only part of the intercooler is super-cooled using peltiers, it WILL reduce the air temp more. Sure not to -60 which may be the surface temp right under the intercooler, but every degree lost as the peltier has taken away some heat is good.

[mickq]

Welcome...hope you enjoy the forum.

A few comments:

Your example with your friend I bet was done at idle speed. What you are seeing there is voltage regulation leading to an idle increase.

If you idle your friends car up to 2000rpm and hold it there, and then turn the stereo on, you will notice the revs wont change. The only reason the revs change at idle is you are asking a huge load for the stereo, the voltage drops and the ecu responds by boosting the revs rather than risk the car stalling due to low voltage.

You can do the same on a car with a carby, and the effect will be the car stalls (or nearly stalls). Its not to do with the alternator creating more load, its to do with the car you did that test in being smart and realising it will stall if the revs dont increase as voltage has dropped to (for example) 9 volts after you turn on the huge stereo. Carby cars generally arent that smart, so they just let the stereo chew the power without changing anything to the point the car will stall as its revs drop and the sparkplugs stop working properly. (It usually takes a few seconds as it stumbles, gets even slower which makes the problem worse, then coughs and dies completely).

As soon as your car is going faster than idle speed, that problem vanishes. And as this is a performance tweak, idle speed isnt the time to measure it!

In a nutshell, I would expect a slight increase in idle speed fuel consumption for sure (for the same reason I mention above) but above that the alternator is just doing what it does...make the same power regardless of what the power draw is.

Also, a decrease in intake temp DOES make more power. As I said, for most typical engines for every 4 degrees you decrease intake temp, you make an extra horsepower. Its related to cooler air being more dense....and as its more dense you can fit more into a cylinder....which means you can also put in more fuel to the cylinder and create a bigger explosion...and thus more power.

I think you would find that the current drawn would put such a load on the alternator that the extra couple of horsepower you would gain would be sapped up by the alternator...

Dave.

<{POST_SNAPBACK}>

The alternators run at a fixed load, do they not? The alternator is "tuned" to put out xxxx watts at 12v across a certain rev range....

<{POST_SNAPBACK}>

First of all Hi all, this is my first post and I'm new to the forums but not new to electronics ;p

The Alternator in your car without getting to much into it produces a fixed (regulated) voltage and a varying amount of current. That is as you turn more stuff on the current draw goes up and the alternator has to produce more power (in Watts) to cope. It does this by converting the mechanical energy from the engine into electrical energy. Easiest way to demonstrate this is find a mate who’s spent more on the stereo for his car than the car is worth. Get him to turn the thing up while the car is at idle and watch the revs load up...

Long story short whatever power you draw from the alternator you lose from the engine…

Having said that intercoolers and turbos’ don’t really make an engine produce more power they just make it more efficient so you can get more usable power from them ( I know that’s confusing). For instance the turbo sucks the energy out of exhaust gas that would normally be wasted and uses it to compress air, thus making the engine more efficient and you go faster…

By using engine power through Peltier’s or an adapted Air Con to make the intercooler work better you MAY make it more efficient overall and get extra rwkw...

Remember you can’t get out more than you put in you can just use it better…

<{POST_SNAPBACK}>

[mickq]

At track speeds it may be a bit different - but on the street a mix of heat soak and high ambient temps definitely results in my T missing power, particularly mid to high rev range. Its that kind of thing I am most interested in targetting.

It would be interesting to measure your actual intake temps at the start, during and after your laps to see the effect over that time.

I think putting a peltier naywhere would be beneficial. Heat accumulates so anywhere you can take it away on the path from your air intake to your engine intake is a good thing. I dont think it would make too much difference where exactly you did it - just pick the most efficient spot where you could mount them to cover the greatest surface area. Cooling the IC is just one idea, as it has some nice surfaces you could attach it to. You could just as easily put it before or after the intercooler. I dont think the actual location would make a difference to your end temperature unless one location gave the air better/longer exposure to the cooler temp.

Would it make the air flowing through the intercooler colder, or will it just make the actual intercooler colder.

I don't know if anyone else has tried this, but after about 15 laps at Wakefield Park, the intercooler was cool enough to touch.

Being a front mount, the air hitting it cools the intercooler enough.

I'm interested in this from a different perspective though. Would it be worth encasing the cold air intake snorkel with this stuff, therefore "icing" the air as it comes into the engine?

<{POST_SNAPBACK}>

[mickq]

I have used them on CPUs too. CPUs are in general very different. They are a very high concentration of heat that never lets up. Its not unusual for a CPU to reach 100 degrees plus and fry itself in about 3 seconds without cooling - especially AMDs .

If an intercooler got that hot, for sure a peltier would not help.

But they dont get that hot, do they...?!?

I have used peltiers on computers for years and as you may know they are a heat pump. The problem is the amount of heat that you are talking about is not realistic for peltiers. I tested this about 4 months ago. The area you are looking at is just not do able.  Also take into consideration, if you dont cool the peltier correctly it wont work correctly, on computers I used water cooling over top of the peltier that we hook upto a small fridge with water located inside of it with a water pimp.

This keeps the water at around 15 'c as the peltier gets hotter the hotter the CPU runs. Imagine the size of the peltiers you would need to cool the car .

<{POST_SNAPBACK}>

[mickq]

I dont think the fact that the turbo will heat it up again is relevant as it wont undo the good done by the initial cooling.

As an example, lets say standard:

Air Box Temp: 20 degrees

After Turbo temp: 45 degres

And compare to a sample airbox peltier idea

Air box/peltier temp: 15 degrees

After Turbo temp: 40 degrees

The point being the turbo adds a certain amount of heat - it doesnt *always* end up with air coming out at a set temperature. If cooler air goes into the turbo, then the temp out of the turbo will be lower. if hotter air goes into the turbo, the outgoing temp will be hotter by as much.

Cool it anywhere along the chain, as the result will be a lower temp for all those parts that come later in the chain. They will still add heat, but since they started with a lower temp, they will end with a corresponding lower temp.

Another quick fix that I've seen used to cool the intercooler is spraying it with nitrous for a few seconds before a run. I'm not sure how expensive this process would be though.

<{POST_SNAPBACK}>

you can use almost any compressed gas to do this

cro, the problem I would see with using the peltiers on the cold air intakes is that the air is still going to pass thrue the turbo which is going to heat it up again alot more efficiently.

<{POST_SNAPBACK}>

hmm too true.

I haven't really looked at the way the piping goes, but I assume after it goes through the turbo it goes through the intercooler.

Maybe cool the pipe between the two?

<{POST_SNAPBACK}>