2014-2020 Formula One 1.6l V6 turbo engine formula

[beelsebob]

Renault don't think that Mercedes' split turbo concept is a game changer - http://www.autosport.com/news/report.php/id/114013

Of course they think that - they don't have it, and their marketing guys have their backs to the wall.

[bhall]

I agree with Renault. I imagine there are indeed advantages to Mercedes' layout, but I think Mercedes' biggest mechanical advantage is the functionality of the split-turbo itself, not the location of the components.



The above just doesn't strike me as a game-changer.

The log-type manifold, on the other hand, seems like it brings a substantial packaging advantage.

[ringo]

They are right. There is no real advantage in it. There's nothing there to give 80hp advantage as some think.
This whole split turbo is the silver bullet thing was fabricated by the media.

The only advantage is a space and slightly improved cooling and theoretically slightly improved response.
Cooling is also nearly negligible because you can design an intercooler to give whatever temp drop you want, or simply have a more efficient compressor.

What Mercedes has is a huge ass turbine and an advance energy recovery system to work with it. That where their advantage is. As for fuel some seem to think it's another major reason, but I'm not so sure and I'm not so knowledgeable on it.
I just feel Mercedes has more energy available to run for all of the lap instead of 33 seconds.

[Juzh]

Renault don't think that Mercedes' split turbo concept is a game changer - http://www.autosport.com/news/report.php/id/114013

Of course they think that - they don't have it, and their marketing guys have their backs to the wall.

This basically. Renault so far this year released so much bullshit to the media I don't believe anything they say at this point.
"we're making progress, we're making progress, we're making progress..."

Advantages might be small, but they are there.

[Blackout]

And yes they are making progress.

I don't believe anything they say at this point

lol and they keep proving that you were wrong from the first day.

The Merc layout do have multiple adavtages and we dont care what medias say. Simply think about it. Even the weight distribution is better with that layout; The gear box casing doesnt need to host a turbine AND a compressor. The merc cars do not need to use as much heat schielding as Lotus for exemple, in order to isolate the compressor from the turbine and the compressor/intercooler pipe from the exhaust pipes.
Etc.

[ringo]

Lotus has gone from the back of the grid, dropping out of Q1 to challenging Ferrari and McLaren. They are making progress.
However the Mercedes is a brute, and for some reason the customer teams don't have the brutal power units the factory team has. Again this seems to be down to the energy recovery and turbine in my book.

[dren]

The customer teams have the same unit that the works team has. The W05 is a good car. It's not just the PU. It's the PU and chassis integration. For this alone it surprises me that Ferrari are not better than they are.

Does anyone know for a fact that the turbine on the Mercedes unit is larger than the rest?

Mercedes had a rather excellent ex TD solely deadicated to PU and chassis integration. Mercedes got a jump on the competition and threw a lot of resources at it. It's no surprise they are as far ahead as they are.

It seems that Mercedes went the route several were guessing at in this thread: high efficiency and large compounding recovery.

[Edax]

I agree with Renault. I imagine there are indeed advantages to Mercedes' layout, but I think Mercedes' biggest mechanical advantage is the functionality of the split-turbo itself, not the location of the components.

The log-type manifold, on the other hand, seems like it brings a substantial packaging advantage.

I wonder whether it also has some other advantages. If I look at closely the log there is something funny about the material. If you look carefully it seems that the tube consists of an inner tube (probably some inconel or similar)and what appears to be a thick layer which is later applied. I have a hard time placing this layer, it does not look like a typical spray thermal barrier(because of the seam). Could be some material which is applied as a decal and post fused. Not a standard production process that I am familiar with. But I guess it has a barrier function.

To me it looks at that the thought behind the whole exhaust architecture is to keep the exhaust gasses as hot as possible. Compared to for instance the ferrari arrangement, the difference in turbine inlet temperatures would be significant.

I wonder what that would bring in terms of turbo efficiency. Because in that case the advantage could be threefold: more efficient packaging, less heat into the side pod, and increased turbo efficiency.

[mrluke]

Lotus has gone from the back of the grid, dropping out of Q1 to challenging Ferrari and McLaren. They are making progress.
However the Mercedes is a brute, and for some reason the customer teams don't have the brutal power units the factory team has. Again this seems to be down to the energy recovery and turbine in my book.

Any thoughts on the software managing the whole process? I feel there is a lot to be gained there and its something unlikely to be shared with customer teams.

[bhall]

[...]

I wonder what that would bring in terms of turbo efficiency. Because in that case the advantage could be threefold: more efficient packaging, less heat into the side pod, and increased turbo efficiency.

It's my understanding that the log-style manifold isn't nearly as efficient as a tubular manifold. I think the advantage is purely one of packaging. (If I tried to explain why, you'd know less about it than when you started. So, I'll leave that to someone more qualified.)

[Edax]

[...]

I wonder what that would bring in terms of turbo efficiency. Because in that case the advantage could be threefold: more efficient packaging, less heat into the side pod, and increased turbo efficiency.

It's my understanding that the log-style manifold isn't nearly as efficient as a tubular manifold. I think the advantage is purely one of packaging. (If I tried to explain why, you'd know less about it than when you started. So, I'll leave that to someone more qualified.)

That is also what I understood, that you want to go for equal lenght. But on the other hand I also understand that you can gain efficiency from a turbine from increasing the inlet temperature. Basically you're throwing away potential work by allowing the gas to cool.

From the arrangement it is pretty clear that the Mercedes turbine is running at higher temperatures. For the log the radiating/convecting surface is simply much less. And from the materials and the way they apply them, I have a pretty clear indication that they are trying keep the gas hot.

What I don't know is whether the thermal efficiency gain would offset the loss from not having equal length headers, or even give an overall gain. For that it would be nice if someone more knowledgable could chip in.

[chip engineer]

Good article about electric power control efficiency improvements using SiC semiconductors to reduce volume and cooling needs:
http://www.greencarcongress.com/2014/05 ... 0-sic.html
I wonder how much of this is already in the various power units. Probably in the Toyota WEC units?

[gruntguru]

[...]

I wonder what that would bring in terms of turbo efficiency. Because in that case the advantage could be threefold: more efficient packaging, less heat into the side pod, and increased turbo efficiency.

It's my understanding that the log-style manifold isn't nearly as efficient as a tubular manifold. I think the advantage is purely one of packaging. (If I tried to explain why, you'd know less about it than when you started. So, I'll leave that to someone more qualified.)

That is also what I understood, that you want to go for equal lenght. But on the other hand I also understand that you can gain efficiency from a turbine from increasing the inlet temperature. Basically you're throwing away potential work by allowing the gas to cool.

From the arrangement it is pretty clear that the Mercedes turbine is running at higher temperatures. For the log the radiating/convecting surface is simply much less. And from the materials and the way they apply them, I have a pretty clear indication that they are trying keep the gas hot.

What I don't know is whether the thermal efficiency gain would offset the loss from not having equal length headers, or even give an overall gain. For that it would be nice if someone more knowledgable could chip in.

A log style manifold will be slightly inferior at capturing all the blowdown energy due to pulse interference at certain engine speeds. OTOH minimising heat loss between the port and the turbine is very important and the log manifold wins with a much lower surface area.

In a similar vein, I have wondered if there is much difference between engines, of air temperature entering the intake port. To my mind, heat rejected to the intercooler is lost energy and should be minimised. The situation is not the same as a normal turbo car where cooler, denser charge means more power. The 1.6 turbo has ample breathing to burn the available fuel - if the charge isn't dense enough, turn up the boost! Less intercooling means hotter exhaust and more energy available to be recovered by the MGU-H ie more power from the same fuel flow. The limiting factor here will probably be thermal stress on the combustion chamber components. This however could be reduced by running more boost and a leaner AFR. DI technology (read stratified charge) makes lean mixtures very do-able and I am sure all the engines are running leaner than stoich' (>14.7:1).

The next bottleneck is turbine inlet temperature. This can also be alleviated by leaner mixture (the energy lost in reduced exhaust temperature is gained in higher mass flow) but will probably be a limiting factor in the end.

All the talk about MB having a larger or superior turbine sounds off the mark to me. Turbine technology is centuries old and Renault knows as well as MB how much energy to expect from a given exhaust flow and temp. Perhaps the secret is an exhaust with higher energy content?

[Tommy Cookers]

we all expected 'tuned exhausts'
(to conserve and use exhaust pressure pulses to provide about 0.2 bar free rpm-related supercharge as race NA and all ? race turbos)
if the turbine is big enough this allows pure blowdown working ie the mean exhaust pressure does not rise above ambient
(turbine work does not raise mean exhaust pressure because there is more energy in the blowdown pulse than the turbine wants)
but we seem to have been only 67% right

for turbine use the log manifold destroys pulses in its process of restriction raising the mean exhaust pressure
this gives pressure working of the turbine, for a given task the turbine will be smaller and more responsive (than blowdown working)

typically in turbos the turbine is relatively small, slightly raising mean exhaust pressure (but largely preserving free supercharge)
in a sense the raised mean exhaust pressure costs no crankshaft power because it is balanced by the (free) boost
(we might call this 'UC useful compromise' working of the turbine)

most of the exhaust energy is anyway lost (to any expander device) by the time it has left the exhaust port (Wright said 65% loss)
raised mean exhaust pressure means a raised density, ie a greater load for the emerging exhaust blowdown to work on
this reduces the loss of useful exhaust energy
so pressure working of the turbine has the potential for higher recovery by an MGU-H
the downside for SI engines is increased temperature in-cylinder (needing lower CR) and a need for more boost and intercooling
NACA showed in 1944 raised exhaust pressure (preserving the pulses ie UC working ?) gave best efficiency (ie compounded)
even into true backpressure
without much problem from increased internal temperatures ?

presumably MB are recovering more exhaust energy than the others
(and using more real-time, there being no hard limit of electrical energy/lap going direct to MGU-K)
with pressure working of the turbine, it wouldn't need need to be bigger than the others
they may have better fuel , ie with an even higher 'unlimited Octane No' (for a given high fuel energy/kg)
their combustion package may in other ways allow high CR despite their higher internal temperatures
and maybe they have designed a PU for the long-term ie to thrive under future reductions in fuel allowance
(pressure working always was more attractive as fuel allowance reduces, because internal temperatures are less problematic)
and are anyway more advanced in their programme than the others

btw the Wright recovered at sea-level economy cruise (boost of 0.17 bar) free power equal to about 6% of crankshaft power
so presumably an NA engine with typical tuned exhaust benefit equivalent to this could do the same blowdown turbine working

[dren]

delete me please...somehow it double posted.