Air to air intercooler question..

[OhSoSlow]

I'm trying to remember my physics days.. and I'm drawing a blank..

Can an air to air intercooler, get your intake air colder than the temperature on the day? e.g it's a 20degree day.. and your intake is is 15C ..

I seem to remember something about wind chill factor?!

[nemesisteg]

my science days are well out of my brain but id imagine it would be quite difficult to tell with all other things considered, heat of intake piping at all points etc etc

[OhSoSlow]

Oh yeah appreciate that .. was more theoretical than anything..

My grey hairs are stealing my brain cells!

[d16a7]

uhm should be able to get it colder than the air temp ... as when you touch the IC it feels cold... in comparison to touching the car...

im trying to remember exactly why its colder.. something to do with surface area? and air speed etc etc...

[OhSoSlow]

Yeah but it feels cold just sitting there.. (i.e. not driving)

Like you walk into a house and stand on tiles, they "feel" colder than the carpet.. even though they're at the same temperature..

[FREEZN]

are they?.........

[Horny_Devil]

yes i will be able to its called wind chill factor

get a lazer thermometer and test it

[OhSoSlow]

What determines the wind chill factor? the faster you go? humidity?

[nemesisteg]

Originally Posted by OhSoSlow

What determines the wind chill factor? the faster you go? humidity?

+ air speed

[Horny_Devil]

ull be supprised at what u can find in 20 seconds with a google/wiki search

http://en.wikipedia.org/wiki/Wind_chill

[OhSoSlow]

hhmm, according to that (which is about humans, but I would presume the same thing would apply) at 100km/h, wind chill drops temp by 10C

Awesome, thanks for the help!

[Horny_Devil]

it depends on the starting temp

if the air temp is 9 deg and ur going 100km/h the aparent temp is 2deg

at 20deg and at 100km/h it gives you 12deg

[d16a7]

and then you also have to factor in head winds aswell wouldnt you.. as the air speed would be 100 + the head wind is the air speed?

so yeah roughly give or take 7-10degrees at 100kph...

[Colza]

This is where water spray is awesome. The evaporation of the water allows you to remove MUCH more heat energy than could be achieved using just air on air.

Remember that people in general are a little wet on the outside, where as your intercooler is probably pretty dry. I would doubt you can get a 10deg drop below ambient without additional liquid to evaporate.

The reason the tiles and the intercooler feel cold when you touch them is because they are both good conductors of heat. They transfer heat away from your fingers rapidly. The air on the other hand is not a very good conductor of heat so doesnt feel as cold to your skin.

[gasman]

its thermodynamically impossible to cool your intake charge below ambient air temperature. the wind chill and tile examples above are the apparent temperatures that you feel because your body heat is getting transfered away from the body quickly so it "feels" colder than ambient.

even with water spray on the intercooler it will transfer the heat away from the charged air quicker than if there was no water spray, but still not below ambient temperatures.

[OhSoSlow]

So you're saying that with an air to air intercooler, theres no way you could get the intake air below 25C on a 25C day? e.g 20C intake air temp?

[gasman]

Originally Posted by OhSoSlow

So you're saying that with an air to air intercooler, theres no way you could get the intake air below 25C on a 25C day? e.g 20C intake air temp?

yea its impossible, same with water to air. the advantage with water to air to is that it takes away the heat faster initially until the water has warmed up also.

you could get cooler than ambient air temps if you run a a/c evaporator in your intake but then the a/c pump will start robbing some of your power.