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[Spencifer_Murphy]

Indeed various WWII fighter planes generated net positive thrust from their radiators by heating and accelerating the air.

Well there goes my "I can't see how the exhausts will be able to heat the air sufficiently" idea

That being said, could it really heat the air ENOUGH? I mean to blow the diffuser to either "seal" it or energise the flow would require some serious increase in velocity, no?

[beelsebob]

Indeed various WWII fighter planes generated net positive thrust from their radiators by heating and accelerating the air.

Ah, interesting. That would seem to support the idea that it should be possible to do this using the radiators and/or exhaust to heat the air and get a reasonably quick flow out. Do you have any good links for which planes did this, and what sort of arrangements were necessary?

Aside – if this works, does it start to break the rule about only being propelled by the engine and the KERS unit?

[Spencifer_Murphy]

Aside – if this works, does it start to break the rule about only being propelled by the engine and the KERS unit?

I was just thinking that, great minds and all that! lol

To be fair I don't think it would (you could argue all cooling (and subsequent heating of the air expelled from the sidepods) does this and hence its not a propulsion device.

But I would bet the FIA use your idea as a way to ban the system if indeed it is true that it works in this way lol.

[myurr]

A quick google later and the effect even has a name: http://en.wikipedia.org/wiki/Meredith_Effect

[Spencifer_Murphy]

My understanding was that the meredith effect produced small gains which helped negate (but not completely) the drag caused by the radiators themselves?

Surely this couldn't be used to provide the substantial gains required for a blown diffuser?...

...could it? *gulp*

(I could easily be wrong...I thought the F-Duct on the MP4-25 was all nonsense when talk of it first started as rumours LOL!)

[shelly]

A quick google later and the effect even has a name: http://en.wikipedia.org/wiki/Meredith_Effect

Discussed n times on this forum also

[beelsebob]

My understanding was that the meredith effect produced small gains which helped negate (but not completely) the drag caused by the radiators themselves?

Surely this couldn't be used to provide the substantial gains required for a blown diffuser?...

...could it? *gulp*

(I could easily be wrong...I thought the F-Duct on the MP4-25 was all nonsense when talk of it first started as rumours LOL!)

Surely if you can 1) negate the drag (they're saying net-thrust, so it must fully negate the drag) and 2) heat the air (even a small amount), that's a net gain in two areas? I'm not sure why a team would pass that up.

[volarchico]

The "net thrust" from the Meredith effect was found on a P-52 Mustang. My personal opinion is I doubt that this would work effectively on an F1 car, but here is a diagram from the P-52:

[dren]

The net positive thrust surely isn't anywhere near that of the exhaust. I think the reduction in drag would be of more benefit than the speeding up of cooling air.

[myurr]

To even contribute to negating the drag you need to generate thrust. The car is going to incur the drag regardless of whether this effect is exploited, as they HAVE to cool the engine. So you're paying the price of having radiators, even if they still generate drag overall they are producing thrust and this thrust can be used to blow over the diffuser.

[beelsebob]

Random thought about why this might be even better...

If you can generate net thrust, then you're increasing mass flow out the cooling exit, which means you must be increasing mass flow into the radiator, which means that you're getting more cool air into the radiators, which means you're cooling the engine better, which means you can have smaller radiators. Not only might it give you a little bit of thrust, but also decrease the amount of drag due to a reduction in radiator size.

[Spencifer_Murphy]

Surely if you can 1) negate the drag (they're saying net-thrust, so it must fully negate the drag) and 2) heat the air (even a small amount), that's a net gain in two areas? I'm not sure why a team would pass that up.

Very true, good point. But I am still left wondering if these gains would be enough to be of any real benefit? (in terms of blowing a diffuser to recover whats been lost now that you can't do it with the exhausts - in theory lol).

Who knows...all I do know is I can't wait to see what items are being tested in that exhaust area over the next few days!

EDIT:

Random thought about why this might be even better...

Now THAT is a great idea. Smaller rads, maybe smaller sidepods, overall aerodynamic gain. Beautiful!

[myurr]

EDIT:

Random thought about why this might be even better...

Now THAT is a great idea. Smaller rads, maybe smaller sidepods, overall aerodynamic gain. Beautiful!

Looking at the diagram F1 sidepods already follow that format. Large intake that then expands around the radiator before narrowing to a smaller outlet. Underbody aero is supposed to be as important as the more visible external aero, maybe this is one of the principles that teams are exploiting.

[Pup]

The "net thrust" from the Meredith effect was found on a P-52 Mustang. My personal opinion is I doubt that this would work effectively on an F1 car, but here is a diagram from the P-52:

Is that an adjustable outlet? That would be interesting.

[Spencifer_Murphy]

Looking at the diagram F1 sidepods already follow that format. Large intake that then expands around the radiator before narrowing to a smaller outlet. Underbody aero is supposed to be as important as the more visible external aero, maybe this is one of the principles that teams are exploiting.

Oh yes totally, but I think what Beelsebob was suggesting latterly was if maybe this exhaust pipe-come-heat exchanger idea is further exploiting this concept in terms of improving the cooling of the car even further? (By heating the air even further?)