Duct radiator into exhaust --- Possible?
 

Merge them before the catalytic converter, so you can seal the engine compartment completely (well, after the radiator grill) and have no aerodynamic losses from the air going everywhere and around the engine compartment... ?

This would also boost radiator efficiency since the air would be "ducted" and given an airway path- not just a "go find somewhere" around the engine compartment.

What do you think? Possible?

...exhaust volume is determined by engine RPM, while radiator air is determined by MPH (assuming all else constant)...so you're gonna encounter one heck of a "merging" problem.

...it's possible, but IMHO going to entail LOTs of duct work.

on formula cars as well as sports racers (Formula car with a full body)
The ducting of the air through the radiator has huge effects on speed.

The EVO/Touring Cars all duct their air up through a tuned hole in the hood so as to take the firewall air out of play aerodynamically.

But you have to rethink engine insulation, there is a lot of stuff under the hood that needs some air flow to stay healthy. (Alternator, electronics etc)

Dave

Well I was thinking of a simple y-pipe with a one way valve on the radiator side so the exhaust doesn't go backwards into the radiator...

I think your attacking too deep, what if you just duct the radiator to its own pipe,
It would need to be about 1/4 the size of the radiator... Your radiator needs about 2000 to 4000 CFM depending on the setup. No restrictions allowed. Of course your fan choice would be key, with the right fan the pipe could be smaller...

Dave

I think ducting radiator air to the wheelwells would be better, and easier. This would reduce snow buildup and maybe improve airflow in the wheelwells, which usually have lower pressure than the engine bay.

You'd need a "path of least resistance" setup for the exhuast, so that it could not come back through the vent under low pressure situations.

As was said, yes, it could be done. Special care would need to be taken, though.

When I first read this, I read it as (duct radiator through exhaust) meaning: (run coolant through a radiator fitted to the exhaust pipe to cool the engine). I was all prepared to tell you why it just wouldn't work. ;)

The added benefit of running your heated radiator airflow to the exhaust is that:
At low radiator velocity, high exhaust velocity, the exhaust will act like a siphon flow, pulling more air through the radiator via negative pressure at the back of the radiator's surface.

At high vehicle speed/low engine speed - the excess flow from the radiator, ducted smoothly into the exhaust pipe, would work to increase scavenging due to a siphon flow effect creating negative pressure on the back of the valves, increasing the pressure differential across the face of the valve as it opens.

At a high enough speed with low enough engine speed (not even extremes, here), one could experience lowered pumping losses due to the piston no longer having to apply nominal pressure to the exhaust gasses to force them out.

I'm reading it as having an air duct with the exhaust pipe running within it- I mean, if you want something that has a shot at working.

Remember the air flow through the radiator is dependent on zero back pressure behind the radiator, and the air coming into the engine compartment is to cool stuff besides the radiator.. :)

Dave

EXACTLY what I was thinking! And that is 99% the case anyway... unless the fans are on AND you are running above 100mph lol.

I don't know how much restriction a one way valve would give though...

And I also thought about venting them to the wheel wells... but aren't we always trying to remove airflow from them with things like wheel skirts and flat moon discs? Why would we even think about adding more flow there it just contradicts everything I believe...

I think wheel skirts are to keep turbulent air out, but maybe it's OK to let air in in a controlled manner. Here is a sentence from an Interview with BMW aerodynamicist Hans Kerschbaum:

I think this could be an ideal way of venting it into the wheel wells.

Behind the tire pointing out towards the outside so the air has the path of least resistance. What do you think? The best spot?

Venting the warm radiator air into the area in front of the wheel would create a pressure zone over the wheel, preventing the normal air steam from accessing the wheel's surface, meaning you don't need a smooth wheel cover, since your radiator's flow will basically act as a wheel cover anyway.

Using the warm radiator's airflow to do so would also help warm the tires, creating better traction, as well, although marginally.

Well I already have smooth wheel covers anyway. I am thinking venting it behind the tire might be best though.

My reasoning is that throwing it in front of the tire will add more "air" that the wheel (even though it is smooth) has to go through. Also, I am thinking that by adding it in the rear it might also help with the airflow separation that always occurs at the edge of the fender right behind the wheel well in almost every car and make that transition smoother thus eliminating some of that flow separation... ?

If you exit the air in front of the tire, it's being propelled already by pressure, so the tire won't need to "cut through it." It will actually save the tire from cutting through anything, as the warm air circulating near the tire would create a smooth surface for the cooler flowing air to go over. At the same time, the warmer air will be forced backward by the flow around the front of the car, so it's like "excess" airflow that will actually help keep flow attached, I think.

Of course, I can't prove this without a wind tunnel, so it's just a theory.

Makes sense... any other input of infront vs behind the tire?

Once I have some more opinions made Im for sure going to pull the plug on this ... I just need to know where to direct said flow...

Pull the Plug = stop design/testing and deployment.. why would you want to do that? ;)

How about you do in front on the left wheelwell and behind on the right, then test it and let us know the results? Just kidding ;) Though sacrificing the wheelwells for this research would help alot...

What about cars that already vent rad air into the wheelwells: take a look and see how they did it. Of course, each car's aerodynamics is different and what helps one may not work for another.

On the other hand, with our blocked up grilles the airflow into the wheelwells will be almost negligible, so this may not make much of a difference.

Haha true sacrificing them would be the easiest lol ... Hmmm decisions drecisions

and I haven't seen any Cars that vent the air onto the wheelwells so I don't know where to even start