Painting intercoolers

[haison]

Just wondering, is it okay to spray intercoolers? Will it affect it's efficiency? And also what types of paint will suit better?
Cheers in advance

[roadsailing]

for stealth?

this topic has been argued for years (not here so i much i think)

long story short, give it a light coat of radiator black or flat black spraypaint and it should be sweet.

[Miss MR2]

Paint is a plastic and is an insulator to both heat and electricity. Pretty much, the heat wont be able to dissipate from the fins properly and it will greatly reduce the efficiency. Look at getting it anodised instead.

Why do you want to paint it?

[roadsailing]

paint is not a plastic

they paint radiators

good point on the anodising thing, anodise it black (bear in mind that the layer of oxide is also an insulator)

[ill-minded]

that being said, but generally aluminium forms its own oxide layer when left uncoated anyway so anodising wouldn't really be much different anyway
or at least thats what chemistry taught me

[kingmick]

for stealth?

this topic has been argued for years (not here so i much i think)

long story short, give it a light coat of radiator black or flat black spraypaint and it should be sweet.

correct! ten char

[PlacentaJuan]

i can't see how paint will affect its heat transfer capabilities, unless it has full sunlight on it the black might absorb a (small) amount of heat from the light.

anodising will probably have exactly the same effect but cost about one thousand times more.

[ed]

paint? that will just insulate it!!

if you want black (which IS far more thermodynamically effective for a cooler) then you should buy a black annodised one

painting is a silly idea

[Miss MR2]

Although anodising does create an oxide layer on the outside of the fins, the layer is probably both much thinner and harder than paint. Paint will be cheaper than anodising.

And if paint isnt a plastic, what is it then?

[ed]

i can't see how paint will affect its heat transfer capabilities, unless it has full sunlight on it the black might absorb a (small) amount of heat from the light.

anodising will probably have exactly the same effect but cost about one thousand times more.

that whole statement is wrong...

paint is an insulator
black will cool more efficiently
annodising will be far more effective

[Miss MR2]

i can't see how paint will affect its heat transfer capabilities, unless it has full sunlight on it the black might absorb a (small) amount of heat from the light.

anodising will probably have exactly the same effect but cost about one thousand times more.

The heat from the water in the cooler is transferred into the metal pipe walls and then into the fins on the cooler. The purpose of the fins is to provide a large surface area to volume o fmetal, which increases the rate of heat transfer. Normally, the heat is transferred from the fins to air by convection. However, if the fins are covered in a layer of paint, which is an insulator, the heat does not come into contact with air and does not transfer through the paint bwell, so it is trapped in the metal and it will just continue to build up.

[fester]

I'm with shinybluesteel on this one. Paint it. The cost of annodising would far outweigh the benefits and if paint was such an insulator and bad why have radiators been black painted for so long. Alloy have only been in a relatively short time and manufacturers are not totaly silly.

The amount of insulating that paint provides is so marginal it would hardly count. Last time I was in a black car there wasn't much discernable insulation from the paint. In fact it asorbs the heat. Remember white car much cooler than black car.

If you are worried about normal paint being "plasticy" try high temp exhaust paint, it tends to be very dry powdery in it's application but again I doubt there's much in it.

I

[BigWorm]

Hang on a minute, first you need to realise which part of the intercooler does the heat transfer, and that would be the fins. Now unless you soak the thing in paint you would only end up getting paint on maybe 5% of the fin area, and that's if you bothered to paint both the front & the back.

The question is why you want it black, the answer is usually just for stealth, & the best solution is, as has been said, a light coat of flat black over the parts that are visible.
Annodising would cost you somewhere over $100, which going by the price of intercoolers these days would be almost doubling the purchase price.

[Miss MR2]

The amount of insulating that paint provides is so marginal it would hardly count. Last time I was in a black car there wasn't much discernable insulation from the paint. In fact it asorbs the heat. Remember white car much cooler than black car.

If you are worried about normal paint being "plasticy" try high temp exhaust paint, it tends to be very dry powdery in it's application but again I doubt there's much in it.

I

You are actually referring to a different thing here. When you refer to a black car getting hotter than a white car, it is due to black absorbing more light than white. The light (or radiation) creates heat when it is stored in the material's molecules.

Its good advice about the type of paint to use though.

[roadsailing]

i was hoping i could head this one off at the pass for a change, but as it has turned into a thread,

there are a few things to consider:

heat can move in three ways, conduction, convection and radiation.

in an intercooler, heat moves out of the air into the cooler via convection, goes through the metal by conduction, then gets into the air via convection and radiation.

adding paint or anodising reduces (slightly perhaps) the heat flow through the cooler via conduction, but possibly increases the heat flow out of the cooler via radiation, and possibly convection too in the case of anodising (which increases the micro surface area of the sunstrate metal)

one of the best radiators of heat is black anodised alluminium.

having said that, most of the heat probably "gets out" via convection and not so much radiation.

again, if you have a big blingy cooler that you dont want to be visible, just give it a quick hit of export flat black (ie very fine coat, if it still looks blingy then give it another very fine coat) and only of the visible side, and it will be sweet. after you have done this, just dont think about it anymore.