2014-2020 Formula One 1.6l V6 turbo engine formula

[pgfpro]

A dual entry turbine has its own issues that require some type of VGT system to make it work proper and F1 won't allow any VGT system in 2014.

Just needs to be twin scroll.

Oh I thought you were referring to a dual entry like the "mono turbo" that Audi is using?

[wuzak]

A dual entry turbine has its own issues that require some type of VGT system to make it work proper and F1 won't allow any VGT system in 2014.

Just needs to be twin scroll.

Oh I thought you were referring to a dual entry like the "mono turbo" that Audi is using?

I do mean like this:

http://www.quattroworld.com/wp-content/ ... 1-9500.jpg

It doesn't need to be variable vane to work. Just twin scroll.

[pgfpro]

I do mean like this:

http://www.quattroworld.com/wp-content/ ... 1-9500.jpg

It doesn't need to be variable vane to work. Just twin scroll.

My question then is why do you think the mono turbo in your link is using variable geometry vanes???

[wuzak]

A diagram showing the Rolls-Royce Crecy 2 stroke sleeve valve turbocompound engine.



The turbine is a single stage axial flow turbine.

Not sure how much power the turbine gave, but the Crecy had a lot of exhaust energy.

The Allison V-1710-127 (-E27) also had a single stage axial turbine. The base engine was 2000-2200hp, the turbocompound was 2900-3000hp. About 50% power improvement!

[wuzak]

I do mean like this:

http://www.quattroworld.com/wp-content/ ... 1-9500.jpg

It doesn't need to be variable vane to work. Just twin scroll.

My question then is why do you think the mono turbo in your link is using variable geometry vanes???

To improve efficiency and response at varying load conditions. Without variable geometry vanes the turbine would have to be optimised for one specific operating condition.

[pgfpro]

I do mean like this:

http://www.quattroworld.com/wp-content/ ... 1-9500.jpg

It doesn't need to be variable vane to work. Just twin scroll.

My question then is why do you think the mono turbo in your link is using variable geometry vanes???

To improve efficiency and response at varying load conditions. Without variable geometry vanes the turbine would have to be optimised for one specific operating condition.

I guess you kind of made my point then. IMO because the fact that they used variable geometry vanes then shows me that this isn't an improved turbo charger without the use of variable geometry vanes, but more of a design based on fitment into the V of the engine. IMO todays single entry twin scroll with a divided manifold will out perform the mono turbo. My argument is if the mono turbo was a better mouse trap it would be used on todays performance turbo's exclusively.

[wuzak]

I guess you kind of made my point then. IMO because the fact that they used variable geometry vanes then shows me that this isn't an improved turbo charger without the use of variable geometry vanes, but more of a design based on fitment into the V of the engine. IMO todays single entry twin scroll with a divided manifold will out perform the mono turbo. My argument is if the mono turbo was a better mouse trap it would be used on todays performance turbo's exclusively.

How did I prove your point?

I don't know what makes the "mono turbo" different to a normal twin scroll turbo, but as far as I can tell it is a twin scroll turbo with the inlets separated. The whole idea of the twin scroll turbo is to separate the firing pulses of groups of cylinders, with a certain number of cylinders (more than 3?) producing interferences. The twin scroll turbo would be of no benefit if all exhaust is sent to a single inlet, which is then divided into the scrolls. It needs to have separate inlets for each exhaust set (ie that from each of the cylinder banks).

What the mono-turbo does is make it easier for the exhaust pipes to connect to the turbo. If you look at the location of the turbine inlet on the Mercedes-Benz 2014 engine it looks like it may be difficult to get a good entry with the gearbox in place. Turn it to one side or the other and you will end up with some funky exhaust pipe runs.

If you look at the "mono turbo" you can see that the compressor has two "scrolls" as well - two outlets.

[matt21]

Does some kind of valve to connect the two exhaust from each bank together count as variable exhaust geometry?

[wuzak]

Does some kind of valve to connect the two exhaust from each bank together count as variable exhaust geometry?

Possibly, but for what purpose would that be done?

[matt21]

If you can join the two exhausts a lot revs, you could gain better turbine response.
some kind of "simulated" sequential layout.

At low revs: 2 exhausts feed one scroll, other blanked off -> higher massflow -> higher momentum

at high revs: each exhaust feeds one scroll

[autogyro]

Nice to see the RR Crecy again Wuzak.
Makes you think that perhaps they have cottoned on to using the turbo outlet for thrust.
The Crecy gave a huge amount of its performance from exhaust thrust.
I dont think the coander effect will be enough to redirect the exhaust for downforce under braking though.
It is a big angle from the regs.
Should keep Adrian, Rory and the others busy until 2014.

[wuzak]

If you can join the two exhausts a lot revs, you could gain better turbine response.
some kind of "simulated" sequential layout.

At low revs: 2 exhausts feed one scroll, other blanked off -> higher massflow -> higher momentum

at high revs: each exhaust feeds one scroll

The idea of the twin scroll turbo is that there aren't two exhaust streams overlapping at the same time - which can cause loss of scavenging. I'm not sure that combining all the exhaust in one scroll will be of any advantage.

The mass flow in the turbo will be the same. Just the path it gets there will be slightly different.

If there is an advantage for this I doubt that the engines will spend long enough in the speed band to make it worthwhile. The turbo will need assistance in spooling up from those speeds anyway.

[matt21]

The idea of the twin scroll turbo is that there aren't two exhaust streams overlapping at the same time - which can cause loss of scavenging.

I´m aware of this.
You´re right that the mass flow is the same, but the volumetric flow is different.
So if you get all the exhaust gases in one scroll you can achieve a higher exhaust gas velocity which in effect gives you a higher momentum.

Second idea:
Is a bypass of the intercooler allowed? I canot find anything in the rules.
Back in the 80ies Honda had this in order to achieve better throttle response.

[matt21]

BTW, hasn´t there been a paragraph defining something about fluids entering the engine? I cannot find it anymore.

[WhiteBlue]

The idea of the twin scroll turbo is that there aren't two exhaust streams overlapping at the same time - which can cause loss of scavenging.

I´m aware of this.
You´re right that the mass flow is the same, but the volumetric flow is different.
So if you get all the exhaust gases in one scroll you can achieve a higher exhaust gas velocity which in effect gives you a higher momentum.

Second idea:
Is a bypass of the intercooler allowed? I canot find anything in the rules.
Back in the 80ies Honda had this in order to achieve better throttle response.

The twin scroll has only advantages however you look at it. A single scroll would have to distribute one mass flow 360° around the turbine entry with a fairly long path. The twin scrolls have only to cover 180°. So they can be shorter. The exhaust pipes also can be shorter for the engine with exhaust ports on the outside of the V. And it makes for a more compact packaging of the exhaust routes as well. So however you look at it twin scroll has only advantages unless you look at the fabricating costs which are slightly higher. But that has no priority for an F1 project if you can gain some power and better packaging. So I'm fairly sure that all manufacturers will design twin scroll turbine entries.