Surface Cooling instead of Radiators

[Armco Bender]

Since Brabaham tried surface cooling with the BT46 no one else has ever tried surface cooling to do away with the radiators.Do you know why the surface cooling never worked or was perserved with?.I've always wondered why they have never done away with the radiators and used the surfaces on the rear wings and/or side pods for cooling.The radiators must be the last major disruption to the airflow that can be eliminated.Have they ever tried a cooling system such as steam evaporation that was used in speed record aircraft engines prior to WW2?.Just something I've always wondered about,hope an engine expert can tell me the reasons why?.Cheers.

[avsfan733]

don't know from a real technical side but more pratically, think about what would happen if someone lost the rear wing or had to remove the sidepod covers for work. The extra heat would probably also provide some serious changes in aerodynamics and a severe reduction in downforfce. remember hot air is less dense thats why it rises

[Onlooker]

But who knows the expanding air may be trapped between the wing and colder air and increase the downforce.
Somebody far further into that type of Fluids education may solve this one,but not me!
:confused::confused::confused:

[shiny side up!]

I think it has to do with how practical it is to use surface cooling. The actual surface area of a radiator is HUGE because of all the tiny fins. Somehow, you would need to recoup all of that lost surface area. Also, the rate of heat transfer depends on the airspeed, which will be different inside a side pod than it would along the outside skin of a car. The coolant is also heavy, which may place weight higher in the car and require stiffer structures if a surface system is used. That's all before you even consider the flow of the coolant INSIDE the surface. I don't think a system like that would ever be plausible...

[RWC]

Good point armco,i've thought of the same thing myself.
Don't know why they don't do it though-besides the obvious drawbacks such as higher center of gravity and it just being SUCH a major change from what they have(remember all the aerodynamics are interelated,they take a whole lot of time to learn and fine tune)
There's also another possible reason.
I think they use the waste heat of the engine to improve the efficiency of the diffuser-and as the underbody is much more efficient than clean air wings at providing downforce it follows that they would want to use that heat where it would do the most good.
Bear in mind that this is maybe just theory! I'm think i read it somewhere but can't be sure -i don't keep stuff like i should

[Valve Bounce]

Now if they designed the engine as air cooled, and have this fan to cool the engine with (like the Beetle does), then pointed the fan towards the rear of the car, and have the intake for the fan coming from beneath the car,..................

Yeah!! That would work, wouldn't it!
It might even improve the aerodynamics;
it might even improve the downforce, heaven forbid!

[Armco Bender]

Hmmmm yep I've always thought that big rear wing sitting at the back in the airflow would make a good surface cooling radiator.The other thought I had was running the coolant through tiny pipes built into the outer surface of the body work,surely with all the space age tech stuff we hear so much about these days they have materials that can disapate the heat satisfactorally.

Air cooled motor? Valve...you have been looking at my doodles of F1 car designs,you have a front on the car like an F-16 jet with a central air intake under the nose between the front wheels.....Porsche did air cooled in the 60's it worked OK.

[Valve Bounce]

Honda tried air cooled also, but not successfully.

Armco, you can't run coolant through tiny pipes into the surface, or into the rear wing. The smallest of dings would bugger the whole system up.

[Armco Bender]

My surface cooling car will be so far infront it won't get involved in anyone elses dings.

[avsfan733]

Originally posted by Valve Bounce
Now if they designed the engine as air cooled, and have this fan to cool the engine with (like the Beetle does), then pointed the fan towards the rear of the car, and have the intake for the fan coming from beneath the car,..................

Yeah!! That would work, wouldn't it!
It might even improve the aerodynamics;
it might even improve the downforce, heaven forbid!

Your stealing my idea, if you were to put a skirt on it u have the fan car all over again.....kinda like the kart that is half fabricated in my basement right now with a ac fan from a 95 dodge caravan sitting next to it

[evo]

There was an F1 team that did that. I think it was Tyrell. Naturally it was banned by the FIA.

[boyracer]

Not sure how this surface cooling all works, but the impression that I get is that you use a panel as your radiator surface area, the problem here being the same as trying to pull air from a panel surface. The boundary layer over that panel, although very thin would be effctively not moving and as air is a very poor heat transfer medium you would never achieve the same heat rejection as a radiator.Does this make sense ? or should I wonder back into the garage ?

[Morris 1100]

Surface cooling has been tried twice and not worked either time.....

[Armco Bender]

Hmmm you would think in the 25yrs since it was last tried we would have come up with more efficent materials that would make it practical.Brabham obviously at the time thought it had merits.

[Morris 1100]

And when Brabham tested it it didn't work!
So it never raced.... unlike the other car with surface cooling.....

[shiny side up!]

It is an interesting concept, but it has just never been feasible before. Perhaps changes in technology will one day make it a decent, or better alternative to the ancient radiator, but I don't think that day has (or will soon) arrived...

[Armco Bender]

Surface cooling has been tried twice

Who was the other team that tried it?:confused:

[Dave Brand]

Surface cooling was tried on aircraft in the 1930s. Apart from the problems of building a wing which could act as a cooling surface, there was also reason to believe that heat transfer inceased the drag of the wing.

Careful design of radiator systems allowed recovery of a lot of the waste heat in the from of thrust - the 'Meredith effect'. The best known example of this is the North American Mustang. Gross radiator drag was 400lb; 350lb of this was recovered - against a full power propellor thrust of 1,000lb this was a significant gain.

Unfortunately the Meredith Effect is not significant at speeds below 200mph.

[Rhino]

I know they designed a heat sink for the panoz lmp07 gearbox set in the rear diffuser, it didn't work either!

[Marsh]

AVS fan was right. There is simply not enough surface area on a car body. Never mind the weight!

BTW the Brabham fan car did work. So did the Chaparral fan car. They were banned.
http://f1rejects.crosswinds.net/hall/beta/

[avsfan733]

i just did a little math based on the radiator from our car sitting in the garage and a general measuring of a formula car based on the wheel width and length and its not even close not to mention the back up of warm air near the rear and its not even close

[Garp]

On the practical side, the engine bay needs the radiator outlet air for cooling. Especially the engine-exhaust, heats up the engine bay. Where we can find lots of electrical wiring. So with surface cooling you still need engine bay cooling ducts. This in combination with the surface cooling disadvantages it can’t (yet) ad up for some improvements.

On the other side in GT cars they try to get some extra downforce from the radiators. So this is some kind of “surface cooling”.

[Dave Brand]

An important point we've all missed is that, for efficient cooling, the area exposed to the air needs to be in the order of five times the area exposed to the coolant. That's why radiators have relatively small tubes & a lot of fin area. Surface cooling can only give a 1:1 ratio unless the surface is finned, which doesn't seem all that practical to me!

[Speck]

hmm, Porsche tried surface cooling in the late 50's, i think it was on the RSR. It had a cadmium from hood. Don't remember how it did, but just to note: it wasn't used again.