Why does FIA always ban blown exhausts?

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NtsParadize
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Why does FIA always ban blown exhausts?

Post by NtsParadize » Mon Mar 18, 2019 11:44 am

Why does FIA always ban blown exhausts? They banned blown diffusers in 2011, monkey seat and forced side exhausts in 2012. Does it affect the car following (dirty air)?
#NoHalo

Dr. Acula
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Joined: Sat Jul 28, 2018 12:23 pm

Re: Why does FIA always ban blown exhausts?

Post by Dr. Acula » Mon Mar 18, 2019 12:26 pm

NtsParadize wrote:
Mon Mar 18, 2019 11:44 am
Why does FIA always ban blown exhausts? They banned blown diffusers in 2011, monkey seat and forced side exhausts in 2012. Does it affect the car following (dirty air)?
I think you mean exhaust blown aerodynamic elements.
I think the main reason is to prevent things like we saw or more heard during the aera of the exhaust blown diffusor when teams started to develope special mappings for the engine to improve the effect. This could give some teams an advatage beyond simply a few hp more, when they choose to run the engine of a certain manufacturer.

zac510
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Joined: Tue Jan 24, 2006 11:58 am

Re: Why does FIA always ban blown exhausts?

Post by zac510 » Mon Mar 18, 2019 2:28 pm

Prior to Liberty days, the FIA didn't really have any bias against blown exhausts. They mostly just had a bias against any technology that a high-performing or dominating team had. Even then only if it were to fall under the 'aerodynamic purposes' clause, ie mass dampers, FRIC suspension etc, could they do anything about it. It was more about equalizing the field than any bias against blown exhausts.

Big Tea
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Re: Why does FIA always ban blown exhausts?

Post by Big Tea » Mon Mar 18, 2019 4:16 pm

Can I please jump on this bandwagon and ask about bleed air?

Is it A) allowed. And B) worthwhile?

There must be enough surplus from the charging, especially if the MGU-H is to be done away with.

If it is beneficial on airplane wings, is not the same (but reversed?) principle not useful for F1 Cars?
One test is worth a thousand expert opinions

Dr. Acula
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Joined: Sat Jul 28, 2018 12:23 pm

Re: Why does FIA always ban blown exhausts?

Post by Dr. Acula » Mon Mar 18, 2019 5:54 pm

Big Tea wrote:
Mon Mar 18, 2019 4:16 pm
Can I please jump on this bandwagon and ask about bleed air?

Is it A) allowed. And B) worthwhile?

There must be enough surplus from the charging, especially if the MGU-H is to be done away with.

If it is beneficial on airplane wings, is not the same (but reversed?) principle not useful for F1 Cars?
Well, i think the rules do prevent that.
1.23 Engine :
The internal combustion engine including ancillaries and actuator systems necessary for its
proper function.
1.29 Compressor outlet :
A component containing a duct of closed cross section through which all air destined for
combustion exits any compressor.
5.14 Engine intake air :

5.14.1 With the exception of incidental leakage through joints or cooling ducts in the inlet system
(either into or out of the system), all air entering the engine must enter the bodywork through
a maximum of two inlets which are located:
a) Between the front of the cockpit entry template and a point 500mm forward of the rear
wheel centre line longitudinally.
b) No less than 200mm above the reference plane vertically.
c) On vertical cross‐sections parallel to C‐C.
Furthermore, any such inlets must be visible in their entirety when viewed from the front of
the car without the driver seated in the car and with the secondary roll structure and
associated fairing removed (see Article 15.2.6).
The compressor is an engine ancillary so you are not allowed to go somewhere else than to combustion chamber in the end with the air that passed the compressor. At least that's my interpretation of it.

Big Tea
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Joined: Sun Dec 24, 2017 7:57 pm

Re: Why does FIA always ban blown exhausts?

Post by Big Tea » Mon Mar 18, 2019 6:22 pm

Dr. Acula wrote:
Mon Mar 18, 2019 5:54 pm
Big Tea wrote:
Mon Mar 18, 2019 4:16 pm
Can I please jump on this bandwagon and ask about bleed air?

Is it A) allowed. And B) worthwhile?

There must be enough surplus from the charging, especially if the MGU-H is to be done away with.

If it is beneficial on airplane wings, is not the same (but reversed?) principle not useful for F1 Cars?
Well, i think the rules do prevent that.
1.23 Engine :
The internal combustion engine including ancillaries and actuator systems necessary for its
proper function.
1.29 Compressor outlet :
A component containing a duct of closed cross section through which all air destined for
combustion exits any compressor.
5.14 Engine intake air :

5.14.1 With the exception of incidental leakage through joints or cooling ducts in the inlet system
(either into or out of the system), all air entering the engine must enter the bodywork through
a maximum of two inlets which are located:
a) Between the front of the cockpit entry template and a point 500mm forward of the rear
wheel centre line longitudinally.
b) No less than 200mm above the reference plane vertically.
c) On vertical cross‐sections parallel to C‐C.
Furthermore, any such inlets must be visible in their entirety when viewed from the front of
the car without the driver seated in the car and with the secondary roll structure and
associated fairing removed (see Article 15.2.6).
The compressor is an engine ancillary so you are not allowed to go somewhere else than to combustion chamber in the end with the air that passed the compressor. At least that's my interpretation of it.

Thanks.

Would the compressor be allowed to drive an 'external stage' to generate airflow? It would be exhaust driven, but not be a part of the combustion product?

Or alternately, if there was enough benefit, a compressor directly off the battery. I am not too technical on aero, but what I was thinking along is the air equivalent of a surface effect ship (MALS) or to prevent/cause stall without directly 'blowing' the wing.
One test is worth a thousand expert opinions

henry
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Joined: Mon Feb 23, 2004 7:49 pm
Location: England

Re: Why does FIA always ban blown exhausts?

Post by henry » Mon Mar 18, 2019 6:49 pm

Big Tea wrote:
Mon Mar 18, 2019 6:22 pm
Dr. Acula wrote:
Mon Mar 18, 2019 5:54 pm
Big Tea wrote:
Mon Mar 18, 2019 4:16 pm
Can I please jump on this bandwagon and ask about bleed air?

Is it A) allowed. And B) worthwhile?

There must be enough surplus from the charging, especially if the MGU-H is to be done away with.

If it is beneficial on airplane wings, is not the same (but reversed?) principle not useful for F1 Cars?
Well, i think the rules do prevent that.
1.23 Engine :
The internal combustion engine including ancillaries and actuator systems necessary for its
proper function.
1.29 Compressor outlet :
A component containing a duct of closed cross section through which all air destined for
combustion exits any compressor.
5.14 Engine intake air :

5.14.1 With the exception of incidental leakage through joints or cooling ducts in the inlet system
(either into or out of the system), all air entering the engine must enter the bodywork through
a maximum of two inlets which are located:
a) Between the front of the cockpit entry template and a point 500mm forward of the rear
wheel centre line longitudinally.
b) No less than 200mm above the reference plane vertically.
c) On vertical cross‐sections parallel to C‐C.
Furthermore, any such inlets must be visible in their entirety when viewed from the front of
the car without the driver seated in the car and with the secondary roll structure and
associated fairing removed (see Article 15.2.6).
The compressor is an engine ancillary so you are not allowed to go somewhere else than to combustion chamber in the end with the air that passed the compressor. At least that's my interpretation of it.

Thanks.

Would the compressor be allowed to drive an 'external stage' to generate airflow? It would be exhaust driven, but not be a part of the combustion product?

Or alternately, if there was enough benefit, a compressor directly off the battery. I am not too technical on aero, but what I was thinking along is the air equivalent of a surface effect ship (MALS) or to prevent/cause stall without directly 'blowing' the wing.
A further regulation:

5.8.1 With the exception of incidental leakage through joints (either into or out of the system) and power unit breather fluids, all and only the fluids entering the compressor inlet and fuel injectors must exit from the engine exhaust system.
Fortune favours the prepared; she has no favourites and takes no sides.
Truth is confirmed by inspection and delay; falsehood by haste and uncertainty : Tacitus

Dr. Acula
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Joined: Sat Jul 28, 2018 12:23 pm

Re: Why does FIA always ban blown exhausts?

Post by Dr. Acula » Mon Mar 18, 2019 6:56 pm

Big Tea wrote:
Mon Mar 18, 2019 6:22 pm
Thanks.

Would the compressor be allowed to drive an 'external stage' to generate airflow? It would be exhaust driven, but not be a part of the combustion product?

Or alternately, if there was enough benefit, a compressor directly off the battery. I am not too technical on aero, but what I was thinking along is the air equivalent of a surface effect ship (MALS) or to prevent/cause stall without directly 'blowing' the wing.
It's only one single stage compressor allowed. Also a compressor only for aero benefits would basically be active aerodynamics.

Big Tea
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User avatar
Joined: Sun Dec 24, 2017 7:57 pm

Re: Why does FIA always ban blown exhausts?

Post by Big Tea » Mon Mar 18, 2019 7:09 pm

Thanks guys
One test is worth a thousand expert opinions

j2004p
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Joined: Wed Mar 31, 2010 5:22 pm

Re: Why does FIA always ban blown exhausts?

Post by j2004p » Mon Mar 18, 2019 7:42 pm

I’ve always seen it that the FIA tend to ban items which would likely result in an R&D arms race in that particular area which would massively benefit the better funded teams as they’d be able to pour far more resource into the technology.

Jolle
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Joined: Wed Jan 29, 2014 9:58 pm
Location: Dordrecht

Re: Why does FIA always ban blown exhausts

Post by Jolle » Tue May 14, 2019 10:30 pm

byronCax wrote:
Tue May 14, 2019 10:10 pm
just received my hel braided lines for my 1985 S3 but why did they give me 5 lines & where does does the xtra one go??? please help
strange place to ask this.... but maybe at the master brake cylinder? or did they give you a clutch hose as well? :P