When surfing around I noticed in some naked McLaren pics that their radiators are very simple/boxy. I know Ferrari had theirs tilted with a compound angle, and theirs even was shaped to maximize its area in the sidepod. McLaren howerever have them mounted verticly only rotated with the outer edges farther forward, and with a simple squared section. I wouldnt think there would be a bad affect on drag having a complex angle on the radiators, and ferrari's system provides more surface area while reducing its frontal area. Not only that but the radiator's cross section looks kind of like an F1 fuel tank, hugging all surounding areas. Anyone know why McLaren would take such a simple aproach? I could see this coming from Minardi or the like but you'd think McLaren has the money and manpower to develope more complex cooling systems. Perhaps its not performance gain, but they simply decided to focus on other areas of the car as the radiators are sufficient. Looks like they took making it "simple" to heart. Even seeing this you know there is so much going into this, for example the inlet going into the radiator, and the chimneys and such, trying to get that hot air out of there as well as possible. Sorry no time to post pics. Anyone else make anything of this?
well I must admit there's one thing I don't quite understand about the Ferrari radiators.
I know the radiators are tilted forward at the top and the outer sides, but what is really the advantage of that? I can't imagine the radiator is more efficient then, as the same amount of air still cools the radiators. I thought only the amount of air passing through a heat exchanger mattered.
Of course there is the outer aero, which may well benefit from tilted radiators, but it's in my view just some approach... McLaren is clearly satisfied with the radiator placement (btw, Williams have this layout too). Point is that at Williams for example, they made the radiators wide but low.
So.. I my point of view, the Ferrari layout just complicates things for no advantage at all, anyway, the Ferrari sidepods are a story on their own, so I can understand ( a little)
complication does not promise performance gain.fw25 is so simple outside till I keep thinking whether its aerodynamic is really good or not.but the car performs brilliantly.Mclaren was messing around with complicated design on their mp4-18 and end up terribly unreliable.
radiator shape is dictates by the sidepod design I guess.Ferrari is using a sloping and curvy sidepod design and hence the tilted radiator.but mp4-17 is just conventional in this aspect.but with mp4-18 I think its gonna have a complicated looking radiator.
The biggest problem with the passage of the air that cools the radiators is not so much in entering and passing through the radiators, but returning it to the high speed airstream around the car. This is because the air is effectively slowed down, relative to the surrounding airstream around the car, firstly by the increasing crossectional area in the radiator duct and secondly as it passes through the radiator core.
Slow air entering the air stream will cause drag. The teams used to feed this slow air back into the air stream above the diffuser, with some benefit in downforce. This season especially, they are now reactivating (speeding up the flow) some of air with the periscope vents around the exhaust, using the high energy exhaust gasses to suck the air from the side pods, with a venturi effect inside the periscope and accelerate it again. Effectively sucking and accelerating the air from inside the pod, by using the energy in the exhaust gas.
Interestingly Renault is also using the periscope side vents on the outside of the pod, first introduce by McLaren a couple of seasons ago, to feed the slow air from the pods onto the top surface of the winglets ahead of the rear wheels. I think this effectively increases the speed differential between the upper and lower surfaces of the aerofoil, thus increasing downforce. Not sure if it helps with the air flow around the rotating rear wheels to, maybe one of the experts with CFD can let us know?
Finally one of the reasons the engine builders have been trying to raise the operating temperatures of their engines is to reduce their cooling requirements and thus the total airflow required through the side pods. It’s all to do with temperature differential, the higher the temperature differential is between the radiator and the cooling air, the faster the heat energy will flow from the radiator to the cooling air. This effectively allows the teams to reduce the size of the cooling system and the volume of air required to maintain the correct engine temperature.
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Well there could be a quite easy answer to the question....usually I like to look at the size of radiator intake from one year to the other, especially when teams keep the same engine (without too much development)....this usually is an easy way to find out if the amout of air that the engine needs has been reduced.....this means that the engine can resiste to higher temperatures.
In Ferraris case the tilted radiatores....have helped them with the narrower side pod....but....the bigger radiator area means that the drag will be bigger cause the drag is proporcional to the area....but....... bigger radiator area has 1advantage....engine cooling...but if they need better engine cooling does it mean that the engine isn't very tolerate to high temperatures?...it might be true....
the other disadvantage is that the radiator is slightly tilted to the back....which pushes the CofG slightly to the back.....which isn't an advantage.....
well one good reason of having them tiped forward is it will lower the cog. another thing to look at, is McLaren and Williams with their simple radiator layout didnt seem to need the gills or whatever they are called that ferrari is running on the sidepod. itd be nice to somehow know how much surface area the teams are using, that is tough to know, but what is easier to know is checking the radiator intake like monstrobolaxa said.
I wonder how hot the engines get before race start, the leaders sit there for a substantial amount of time, and i have not seen fans behind the radiators like in most of our street cars. strange how such an almost overlooked thing can affect your ability to even finish races. obviously you want to finish the race, but you want to create as little drag as possible-which means pushing the engine as hot as you can bear.
Suppose the frontal area of the radiators are the same (just looking straight from the nose onto the radiators, and thus not really noticing the tilt forward), what is then the advantage?
Is it maybe useful for Ferrari to have the air flowing through the radiators more spread out (since the real surface, seen from beside is bigger then Williams') although for the same amount of air.
The advantage in tilting the radiator forward is surface area. Convection heat transfer is a function of surface area so the more surface area you have, the greater the heat transfer. Therefore, by tilting the radiator system, there is a greater ratio of surface area of the radiator to frontal area.
The disadvantage of tilting the core, is that if the it is a normal style radiator, the cooling fins are perpendicular to core. If that is the situation, then you have change the direction of the flow through the cooling system, there will be a loss in momentum, and hence more drag. In the ideal world, you want the flow to enter and exit normal to the radiator core. A small change in flow direction is acceptable.
So by tilting the radiator core in two directions, the change in direction the flow make going through the core is smaller and therefore, less drag from the internals.
I think Ferrari have found a better solution. I suspect that since the radiators are completely custom made (as opposed to using off the shelf core material), the cooling fins are aligned with the flow. So that have the advantage of the greater surface area to frontal area ratio while not incurring the increase in drag.
