Mach929

iTrader: (3)

how much heat any given intercooler can dissipate without air flowing throught it? estimates? in other words looking for an intercoolers effectiveness when it isn't placed with air flowing directly through it.

Joe Perez

iTrader: (8)

After it heatsoaks? None.

Well, almost none. There will be a tiny amount of radiant dissipation, assuming the surrounding environment is cooler than the air coming out of the compressor.

This kind of question begs a more detailed explanation.

240_to_miata

iTrader: (2)

your talking about summing up about 3 different thermodynamic mechanical engineering classes into one answer. I wish i could answer this, but ive barely touched on heat exchangers so far...

cardriverx

iTrader: (12)

well im still in high school but..

with no air flow, when you start the car, the intercoole will be at amibant temp. Thus it will cool the intake charge to this temp untill the intake charge gets the intercooler hotter and hotter untill they are the same (heat soaked). at that point the only thing cooling the intercooler would be the temp difference between the intake charge and the outside air, but since the outside air is still, the intercooler is not dissapateing much heat.

Of course if the intercooler was HUGE it would work better....

Joe Perez

iTrader: (8)

Fill the "atmospheric" portion of the core with paraffin wax, and seal it completely.

budget racer

iTrader: (1)

ummmmm......why the hell would you bother with an air/air intercooler if you didn't have airflow? seems pointless.

as the rest said.....it'll probably have some effectiveness until it's temp comes up to charge temp.

The_Pipefather

iTrader: (5)

unless the intercooler is placed inside of the engine bay where it has no access to ambient airflow, is it even possible that "heatsoak" can occur? Isnt this term more relevant to water-air intercoolers?

Mach929

iTrader: (3)

well this is more or less what i'm asking, if an intercooler was placed in a position where air was turbulent around it but not necessarily flowing though it, what are the effects? aka smic with no ducting? If ambient temp is 75 degrees and charge temp is 140, there's pretty much no way inlet temps will be 140 regardless of air flow through the intercooler. i'd like more discussion here as i'm not sure of all the forces at play since i stopped studying engineering 8 years ago

deliverator

iTrader: (14)

Heat soak is a problem generally associated with top-mount intercoolers (as are stock on turbo Subarus) and water to air ic's.

A properly sized, properly designed front mount setup should not have heat soak issues.

Joe Perez

iTrader: (8)

I really think the only way you're going to figure this one out is by experimentation. I don't recall anything from Thermo or Properties of Materials that would be of much use in calculating the rate of heat transfer from a metallic body of complex and unknown and complex geometry into a surrounding body of turbulent air moving at an unknown velocity and direction.

If there is, in fact, zero airflow through the core, then upon seeing increased charge temps, the intercooler will initially absorb a great deal of heat out of the intake air, gradually rising in temperature itself. As this occurs, the rate of heat absorption will decrease, rapidly approaching zero. After the charge temps drop back down, the intercooler will begin transferring heat back into the intake airflow, cooling itself down to the temperature of the intake air. The rate at which this takes place will depend largely upon the mass of the intercooler, but we're talking seconds, maybe fractions of a second.

If there is "some" airflow through the core, then there will be "some" heat exchange away from the intercooler, into the atmosphere.

Is there a practical reason for this? I think we can all agree that it's going to be non-optimal, and that depending on the constraints that preclude a traditional FMIC to begin with, some other solution such as a water-air intercooler might be a viable alternative.

Mach929

iTrader: (3)

lol i have a fmic on my miata. But i've seen people with ghetto setups go as far as mount an intercooler in the engine bay, i'm just wondering how well it could work, obviously i know it isn't optimal, then i've seen oems smic intercooler solution and i just can't imagine they're getting all that much air through it. Then i've seen STS turbo kits that are rear mount turbo and just run a pipe from the rear of the car to the front stating that that is sufficient to cool the charge. I'm not at all knocking a good ole fmic intercooler setup i was just curious.