Rear Mounted rad n other trickery!

[UltArc]

Originally Posted by Tesla

Here's a Lexus concept, don't know if they ever went anywhere with it.
Fourwheelsteer: Motoring Writer: Weird Tech: Lexus rear mounted radiator

Without all the considerations of engineering problems,
Is it aerodynamically advantageous to eject hot air into the wake to reduce drag, this being for both cooling system and exhaust?

So really, is there any significant aero benefit possible with this idea to warrant spending the time required to overcome the engineering and design issues?

Is this a serious statement? The Lexus LFA!!! Not my favorite or even preferred high performance car, but for manufacturing and technology, it really is fantastic.

Lexus LFA | Supercar | Explore the vehicle | Lexus.com

I don't know if it is better for cooling, but from what others have mentioned, it seems so. And it makes sense to put the exhaust in a low pressure zone, and pull it from underneath the car, I would expect creating downforce.

Significant, I think so. Reducing drag up front, increasing downforce at speed, and helping the wake. Just looking at these individually is probably fairly small, but combined should add a bit. And other than that initial build for the LFA, the design seems simple. Once they figured it out, it should be good.

[kach22i]

I did some Google image searches for wind-tunnel and smoke pictures of the Lexus LFA.

I did not find a thing, was hoping to see those rad's in action.

[Tesla]

Well, there you go it was built, I didn't search any further, was following a different research path.
Would be good to see some smoke/wind tunnel shots of radiator performance.
I know the theory is there, how can we quantify potential gains?
Are we looking at 1-2%, or is it 5-10% or other, those details govern the effort to overcome engineering problems in the design application.
Increasing grill block area at front is likely in the order of maybe an additional 1% gain, taking heat and additional air out from under vehicle may also help a bit, say 0.5%. but what is impact at rear?
I don't know how to calculate potential gains there.

[UltArc]

Originally Posted by Tesla

Well, there you go it was built, I didn't search any further, was following a different research path.
Would be good to see some smoke/wind tunnel shots of radiator performance.
I know the theory is there, how can we quantify potential gains?
Are we looking at 1-2%, or is it 5-10% or other, those details govern the effort to overcome engineering problems in the design application.
Increasing grill block area at front is likely in the order of maybe an additional 1% gain, taking heat and additional air out from under vehicle may also help a bit, say 0.5%. but what is impact at rear?
I don't know how to calculate potential gains there.

Me either :/ I get the idea, and I doubt Lexus would invest in such a system on such an advanced car, but I also don't know how to quantify it. I searched, too, for the wind tunnel, but didn't find anything. Makes sense with such a beautiful car, but I also did not do too comprehensive of a search. I look forward to following any more developments in this, although it will most likely never apply to me.

[Tesla]

Just found another article on the LFA:
LFA Technology Features: Aerodynamic Design | LFA | Models | Lexus International
Gives a bit more detail on design ideas, mostly performance, little mentioned on aero.

[freebeard]

Originally Posted by kach22i

I did some Google image searches for wind-tunnel and smoke pictures of the Lexus LFA.

I'd bet you did. Mudgey hasn't posted since 20130814, so I guess it's just us now.

Originally Posted by Google

en.wikipedia.org/wiki/Bugatti_Veyron‎
The width is 1,998 mm (78.7 in) and height 1,204 mm (47.4 in). The Bugatti Veyron has a total of ten radiators: 3 heat exchangers for the air-to-liquid intercoolers.

Anything is possible with enough radiators.

[Tesla]

I had another read of the LEF article, interesting use of heat tunnel to remove other excess heat.
So vehicle has three main heat ejections in rear, the two radiators either side, the two round exits above exhaust for the heat tunnel and of course the single round exhaust pipe, that being another point of interest only going with single exhaust pipe for a V10.

They do not make any mention of the relationship between rear heat exits and Aero benefits.