Ferrari Power Unit Hardware & Software

[Vortex37]

Maybe thee secret button holds the pop-off valve open?

pressing the 'secret button' to hold a 'turbo pop-up valve' open will drop the turbo boost.
anyhow they do not use a pop-up valve, they use a diverter valve which diverts the boost (over-boost when throttle is lifted) back into the non-pressure side of the intake (re-circulate).

Why would you send hot air back into the front end of the system? Especially after new rule 5.6.8 was introduced.

[Vortex37]

In many of the YouTube videos it is quite clear to me that a boost pop off valve is in use. The sound is very different to that of the waste gate. I'll repeat what I said in 2014/5? If you want to stop 'turbo lag' then why allow the turbo to decrease its rotational speed. Lifting off the 'throttle' will produce back pressure, with obvious results. Though you could suggest that the waste gate might come before rather than after the turbine, so leaving it open in closed throttle might be beneficial, but you would need a multi-port system, with an atmospheric air inlet. Whether the blast of ambient temp air is good for the turbine life is debatable. I think the waste gate comes after the turbine. I think that a pop off/boost dump valve has a few advantages. Opening the dump valve during gear shifts/partial throttle etc., allows the MGU-H to maintain max rpm, so no throttle lag. More importantly the MGU is able to produce max power to the MGU-K and/or the energy store, all the time. This is not road car technology where it's open or closed. We are using something like a Moog electrohydraulic valve, for operation in millisecond time periods, for both the waste gate and boost dump. I also suggest a multi-port pop off valve. I would suggest that the extra sensor thing is the FIA wanting to know how much extra energy/power Ferrari are getting from MGU-H and going directly to the MGU-K.

I am still sticking to my 2014/15 idea that designing the turbo part to be extremely light weight rotational mass is not being done here. I think that it might be more like a flywheel design process, with the rotational mass in a different place to that of a normal turbo.

[saviour stivala]

Maybe thee secret button holds the pop-off valve open?

pressing the 'secret button' to hold a 'turbo pop-up valve' open will drop the turbo boost.
anyhow they do not use a pop-up valve, they use a diverter valve which diverts the boost (over-boost when throttle is lifted) back into the non-pressure side of the intake (re-circulate).

Why would you send hot air back into the front end of the system? Especially after new rule 5.6.8 was introduced.

Because it is advantagious to recirculate the already boosted air back into the engine air intake than vent to atmosphere. a (BOV) will vent 100% of boost to atmosphere when it vents off, a re-circulating valve will vent 100% of boost back into the engine air intake, the more presureized the air inside the engine air intake the easier for the compressor to build-up boost, the easier the compressore build-up boost the less heated the air.

[Tzk]

^ this.

You usually cycle the air in a way that it passes from the throttle bodies back to the intake of the turbocharger. This also means the the cycled air will also pass the intercooler and thus be cool when it arrives again at the throttle bodies.

This is done because you don‘t waste energy.

[Tommy Cookers]

Because it is advantagious to recirculate the already boosted air back into the engine air intake than vent to atmosphere. a (BOV) will vent 100% of boost to atmosphere when it vents off, a re-circulating valve will vent 100% of boost back into the engine air intake, the more presureized the air inside the engine air intake the easier for the compressor to build-up boost, the easier the compressore build-up boost the less heated the air.

boost can be lowered to some desired pressure above atmospheric and this air diverted to the intake and recirculated
so a BOV and a diverter ?

many millions of aircraft engines controlled boost entirely by throttling before the compressor
as did the last V16 BRM

though didn't early telemetry (Honda ?) on this site show that turbo rpm was strongly bled down by H action pre-corner
with corresponding H spooling-up on corner exit
I would expect the H spoolup response to be tens of milliseconds, not hundreds

[saviour stivala]

Introducing forced induction needs a way to release the pressurized air when the throttle is suddenly closed, if not pressure can skyrocket and force the air into turbo the wrong direction, this can destroy the engine, the turbo and other components. A (BOV) vents 100% to atmosphere.
Comparing the use of aero-plane piston engine throttle to formula 1 engine throttle is like comparing apples to oranges.
The MGU-H is in total control of turbo, when boost is low MGU-H will spool the turbo up, when boost is reached the MGU-H will slow the turbo down.

[saviour stivala]

I am not “now saying”, I was saying that a (BOV) valve will vent 100% boost to atmosphere, while a diverter valve will vent 100% boost into re-circulation. I was also saying that the MGU-H is in control of the turbo boost, being it maximum boost or lack of it.
The use of aero-plane engine throttle and the use of a formula 1 engine throttle cannot be compared.
And by the way, Rolls Royce the donners of the BRM 1.5L V16 two stage supercharger had after the car was declared impossible to control when its 4.6 ata of boost kicked-in recommended the use of inter-stage throttling of the supercharger be incorporated to provide a power curve more suited to road us, but that and the variable-angle stators at the supercharger inlet were not proceeded with. So the original normal standard must have BOV valve continued to be used.

[henry]

Maybe thee secret button holds the pop-off valve open?

pressing the 'secret button' to hold a 'turbo pop-up valve' open will drop the turbo boost.
anyhow they do not use a pop-up valve, they use a diverter valve which diverts the boost (over-boost when throttle is lifted) back into the non-pressure side of the intake (re-circulate).

Why would you send hot air back into the front end of the system? Especially after new rule 5.6.8 was introduced.

Have a read of the magazine article on the Honda PUs on page 845 of the Honda power unit thread. If I remember correctly there’s a discussion of this and of a change by Honda from hot air to inter cooled air being fed back.

[henry]

Introducing forced induction needs a way to release the pressurized air when the throttle is suddenly closed, if not pressure can skyrocket and force the air into turbo the wrong direction, this can destroy the engine, the turbo and other components. A (BOV) vents 100% to atmosphere.
Comparing the use of aero-plane piston engine throttle to formula 1 engine throttle is like comparing apples to oranges.
The MGU-H is in total control of turbo, when boost is low MGU-H will spool the turbo up, when boost is reached the MGU-H will slow the turbo down.

It is against the regs to blow off to atmosphere. All air entering the intake must come out of the exhaust. You might like to read the Honda article I mentioned in the previous post. (Again?)

[wuzak]

Introducing forced induction needs a way to release the pressurized air when the throttle is suddenly closed, if not pressure can skyrocket and force the air into turbo the wrong direction, this can destroy the engine, the turbo and other components. A (BOV) vents 100% to atmosphere.
Comparing the use of aero-plane piston engine throttle to formula 1 engine throttle is like comparing apples to oranges.
The MGU-H is in total control of turbo, when boost is low MGU-H will spool the turbo up, when boost is reached the MGU-H will slow the turbo down.

It is against the regs to blow off to atmosphere. All air entering the intake must come out of the exhaust. You might like to read the Honda article I mentioned in the previous post. (Again?)

And also illegal to blow into the intake of the compressor, due to the same rule.

Some of the work used compressing the air will be recovered by sending the blow off air through the turbine, while sending it to the exhaust side of the turbine just wastes that energy.

[wuzak]

Could the issue with the Ferrari PU simply be that it has been concluded that the torque delivery does not match driver demand?

[saviour stivala]

“And also illegal to blow into the intake of the compressor, due to the same rule”.
The compressor intake and the engine air intake is one and the same thing, same pathway.

[henry]

Introducing forced induction needs a way to release the pressurized air when the throttle is suddenly closed, if not pressure can skyrocket and force the air into turbo the wrong direction, this can destroy the engine, the turbo and other components. A (BOV) vents 100% to atmosphere.
Comparing the use of aero-plane piston engine throttle to formula 1 engine throttle is like comparing apples to oranges.
The MGU-H is in total control of turbo, when boost is low MGU-H will spool the turbo up, when boost is reached the MGU-H will slow the turbo down.

It is against the regs to blow off to atmosphere. All air entering the intake must come out of the exhaust. You might like to read the Honda article I mentioned in the previous post. (Again?)

And also illegal to blow into the intake of the compressor, due to the same rule.

Some of the work used compressing the air will be recovered by sending the blow off air through the turbine, while sending it to the exhaust side of the turbine just wastes that energy.

The relevant regulation is this:

5.8 Exhaust systems :
5.8.1 With the exception of incidental leakage through joints (either into or out of the system), all (and only) the fluids entering the compressor inlet and the fuel injectors must exit from the engine exhaust system.

It does not deny air going through the compressor more than once. The Honda article I referenced shows this very clearly.

[djones]

Maybe its just as simple as they had the ability to run both batteries in series on demand.

If they put the original sensor one of the batteries, then it would only ever show the voltage/output from that one. Presumably they now have a sensor on both batteries and they add it together and divide by two to see if they were breaking the rules.

[saviour stivala]

Incredible and unbelievable reasoning to suggest that at formula one level if somebody have two batteries instead of one there is the possibility of bypassing the mandatory policing by one sensor, more so when it has been declared by both FERRARI and the FIA that FERRARI had that battery set-up since the start of the hybrid formula in 2014.