Honda Power Unit Hardware & Software

[saviour stivala]

....on the one hand it is suggested that fuel is burned in the exhaust ‘to jet power the turbine’ while on the other hand the waste-gate/s are opened to reduce back-pressure. Sounds like it have been forgotten that when waste-gate/s are opened the exhaust gasses are bypassing the turbine and so not powering the turbine.

the turbine is significantly powered WGO by the exhaust pulse blowdown
(there's no 'backpressure'- mean exhaust pressure is 1 bar)
this is the 'free' power as used by 15000 airliner 'TurboCompound' engines before the jet airliner came along

couldn't some timed injection and/or skip-firing be used to increase pulse action ?
a stationary pulse-jet will produce thrust with intake pressure at 1 bar

“The turbine is significantly powered ‘WGO’ by pulse blowdown”. If by ‘WGO’ you mean (WASTE-GATES OPEN). When the formula 1 power unite is running with waste-gates open and so with the exhaust gasses bypassing the turbine (free load mode) and so not doing any work on the turbine. The reduction in exhaust back pressure will result in an additional power output gains by the engine.

[dren]

....on the one hand it is suggested that fuel is burned in the exhaust ‘to jet power the turbine’ while on the other hand the waste-gate/s are opened to reduce back-pressure. Sounds like it have been forgotten that when waste-gate/s are opened the exhaust gasses are bypassing the turbine and so not powering the turbine.

the turbine is significantly powered WGO by the exhaust pulse blowdown
(there's no 'backpressure'- mean exhaust pressure is 1 bar)
this is the 'free' power as used by 15000 airliner 'TurboCompound' engines before the jet airliner came along

couldn't some timed injection and/or skip-firing be used to increase pulse action ?
a stationary pulse-jet will produce thrust with intake pressure at 1 bar

“The turbine is significantly powered ‘WGO’ by pulse blowdown”. If by ‘WGO’ you mean (WASTE-GATES OPEN). When the formula 1 power unite is running with waste-gates open and so with the exhaust gasses bypassing the turbine (free load mode) and so not doing any work on the turbine. The reduction in exhaust back pressure will result in an additional power output gains by the engine.

Do the waste gates completely block flow to the turbine when they are open?

[saviour stivala]

The formula one waste-gates when opened does not block exhaust gas flow to turbine, they bypass exhaust gas flow from turbine through their own exhaust tail-pipe. The waste-gates exhaust intake connection is from exhaust manifold and is before the exhaust manifold connects to turbine.

[NL_Fer]

Guy, don’t forget about the engine needs to rev up on every downshift, automatic heal-and-toe. There are two ways, one is to use the K, other is use the throttle.

Using the throttle for rev-up on downshift, is a few seconds more K time for full throttle.

[GhostF1]

The reason why i say it is not primarily for antilag is this..
Antilag is to increase turbine speed and thus boost pressure.. That doesnt translate at all to MGUH.

In fact the MGUH is a load it self that slows down the turbine. Of course we are pumping energy into it to keep it at the optimimum speed..

And we dont need that much boost for such an aggressive anti-lag meassure. Notice the other teams arent doing it and we have tonnes of grip in F1. Even these cheese pirelli's they were burning up with the naturally aspirated engines out of the corners. We would be breaking driveshafts and burning thru tires like a barbeque with these boosted engines and K motors.

I really feel its mostly for ERS than anti-lag.

You've got a good answer in your own post there. I don't believe increase in boost pressure is target goal for what we are talking about when mentioning anti-lag, but maintaining of turbine speed would be a side effect of doing it. You say "in fact the MGU-H is a load itself that slows down the turbine". Yes correct, but they are geared 1:1 by the regulations so theoretically, using an anti-lag system to spin the turbine while the H is loading it (in generation mode) would generate electricity no?

[GhostF1]

Had another random idea.

A while ago we were debating whether or not Honda had a clutch between the MGU-H and turbo (brought on by their class of the field performances at high altitude tracks) this is allowed by the regulations, we had decent reasons for both sides (complexity was one, even Renault said they wouldn't due to complexity), I still believe it's likely Honda do, even more so now with the onset of this anti-lag discussion. My main reason for believing in this clutch idea was the theoretical gain in compressor speed it allows. The turbo is not speed restricted but the MGU-H is restricted to 125,000rpm by the regulations, these two have to be geared 1:1 as well so it poses a hard limit on the turbo speed therefore maximum boost potential. So there was an argument Honda could decouple the MGU-H from the turbo at maximum power on straights to allow for an increase in turbine speed to compensate for the altitude deficit, it would also make sense as it seemed evident they may have gotten the mapping a little off sometimes, hence Max's mentioning of turbo lag out of some corners on occasion last year, that was the theory.

So now I am thinking.. why is this anti-lag sound/behaviour most prevalent during high power/quali laps since late last year and not really anything less than that (during sustained race modes, it is not present)? We are talking about it like it's primary use would be for energy recovery benefits and while it is possible, what I'm thinking, mainly because it's most obvious on fast laps, is what if this anti-lag is being used on high power modes as Honda have decoupled the MGU-H and are therefore free to run the turbo at as high an RPM as they want, no longer restricted to the 125,000rpm limit of the MGU-H. This anti-lag is a system which has become available to Honda with skip-fire use so are they using this to compensate for MGU-H motoring loss to sustain the turbo? Or is it to keep the turbine at a certain speed to recouple the H momentarily for power out of corners? Or would that even still be necessary if this is mapped correctly? Or a myriad of other things.

The work with Honda Jet, a lot of focus has been around the turbo from Honda, it's what they bring up all the time. I can't initially see why this is not a possibility for high power modes with the right engine and the right fuel allowing such high boost. Spec 4 and the special new fuel anyone?

[sn809]

Had another random idea.

A while ago we were debating whether or not Honda had a clutch between the MGU-H and turbo (brought on by their class of the field performances at high altitude tracks) this is allowed by the regulations, we had decent reasons for both sides (complexity was one, even Renault said they wouldn't due to complexity), I still believe it's likely Honda do, even more so now with the onset of this anti-lag discussion. My main reason for believing in this clutch idea was the theoretical gain in compressor speed it allows. The turbo is not speed restricted but the MGU-H is restricted to 125,000rpm by the regulations, these two have to be geared 1:1 as well so it poses a hard limit on the turbo speed therefore maximum boost potential. So there was an argument Honda could decouple the MGU-H from the turbo at maximum power on straights to allow for an increase in turbine speed to compensate for the altitude deficit, it would also make sense as it seemed evident they may have gotten the mapping a little off sometimes, hence Max's mentioning of turbo lag out of some corners on occasion last year, that was the theory.

So now I am thinking.. why is this anti-lag sound/behaviour most prevalent during high power/quali laps since late last year and not really anything less than that (during sustained race modes, it is not present)? We are talking about it like it's primary use would be for energy recovery benefits and while it is possible, what I'm thinking, mainly because it's most obvious on fast laps, is what if this anti-lag is being used on high power modes as Honda have decoupled the MGU-H and are therefore free to run the turbo at as high an RPM as they want, no longer restricted to the 125,000rpm limit of the MGU-H. This anti-lag is a system which has become available to Honda with skip-fire use so are they using this to compensate for MGU-H motoring loss to sustain the turbo? Or is it to keep the turbine at a certain speed to recouple the H momentarily for power out of corners? Or would that even still be necessary if this is mapped correctly? Or a myriad of other things.

The work with Honda Jet, a lot of focus has been around the turbo from Honda, it's what they bring up all the time. I can't initially see why this is not a possibility for high power modes with the right engine and the right fuel allowing such high boost. Spec 4 and the special new fuel anyone?

This is an excellent summation and likely true.

[JonoNic]

Had another random idea.

A while ago we were debating whether or not Honda had a clutch between the MGU-H and turbo (brought on by their class of the field performances at high altitude tracks) this is allowed by the regulations, we had decent reasons for both sides (complexity was one, even Renault said they wouldn't due to complexity), I still believe it's likely Honda do, even more so now with the onset of this anti-lag discussion. My main reason for believing in this clutch idea was the theoretical gain in compressor speed it allows. The turbo is not speed restricted but the MGU-H is restricted to 125,000rpm by the regulations, these two have to be geared 1:1 as well so it poses a hard limit on the turbo speed therefore maximum boost potential. So there was an argument Honda could decouple the MGU-H from the turbo at maximum power on straights to allow for an increase in turbine speed to compensate for the altitude deficit, it would also make sense as it seemed evident they may have gotten the mapping a little off sometimes, hence Max's mentioning of turbo lag out of some corners on occasion last year, that was the theory.

So now I am thinking.. why is this anti-lag sound/behaviour most prevalent during high power/quali laps since late last year and not really anything less than that (during sustained race modes, it is not present)? We are talking about it like it's primary use would be for energy recovery benefits and while it is possible, what I'm thinking, mainly because it's most obvious on fast laps, is what if this anti-lag is being used on high power modes as Honda have decoupled the MGU-H and are therefore free to run the turbo at as high an RPM as they want, no longer restricted to the 125,000rpm limit of the MGU-H. This anti-lag is a system which has become available to Honda with skip-fire use so are they using this to compensate for MGU-H motoring loss to sustain the turbo? Or is it to keep the turbine at a certain speed to recouple the H momentarily for power out of corners? Or would that even still be necessary if this is mapped correctly? Or a myriad of other things.

The work with Honda Jet, a lot of focus has been around the turbo from Honda, it's what they bring up all the time. I can't initially see why this is not a possibility for high power modes with the right engine and the right fuel allowing such high boost. Spec 4 and the special new fuel anyone?

This is an excellent summation and likely true.

Could also be the reason why the Honda PU ran about a 1000 revs higher than anyone else.

[PlatinumZealot]

Earlier in this thread this was discussed.
Using similar size turbochargers from the motorsport industry it was shown that therebis a lot of head room in turbine speed for the current level of boost pressure even in at high elevation race tracks and a clutch would be additional weight not really necessary when you can electrically decouple the MGUH.

The other issue of the clutch is balance. You now have an additional weight spinning in the middle of a long shaft at extreme rpms... I dont think any designer would do this. Even electric cars dont have any clutches.

[JonoNic]

Earlier in this thread this was discussed.
Using similar size turbochargers from the motorsport industry it was shown that therebis a lot of head room in turbine speed for the current level of boost pressure even in at high elevation race tracks and a clutch would be additional weight not really necessary when you can electrically decouple the MGUH.

The other issue of the clutch is balance. You now have an additional weight spinning in the middle of a long shaft at extreme rpms... I dont think any designer would do this. Even electric cars dont have any clutches.

Can the whole outside area of that shaft be used as a clutchclutch? Kind of like enclosing the shaft. So the engagement moves along the length of that surface?

[GhostF1]

Earlier in this thread this was discussed.
Using similar size turbochargers from the motorsport industry it was shown that therebis a lot of head room in turbine speed for the current level of boost pressure even in at high elevation race tracks and a clutch would be additional weight not really necessary when you can electrically decouple the MGUH.

The other issue of the clutch is balance. You now have an additional weight spinning in the middle of a long shaft at extreme rpms... I dont think any designer would do this. Even electric cars dont have any clutches.

We do not actually know the exact specifics of any F1 turbines or how the PU is run or anything of the sort to do with programming a device like the MGU-H attached to a turbo in the first place. So we can't just compare to typical road car turbos and write off the idea.
The idea of weight being a concern for said clutch hardly applies either as there is an imposed minimum total PU weight in the regulations, so the marginal weight gain can easily be saved elsewhere.
Clutching the device is literally mentioned in the regulations as allowed.. It's not the stuff of science fiction here. It is technically feasible and the idea is sound. A simple weight balance issue is something they can handle, and interestingly, have handled in the past without talking specifics (see the entire nightmare of getting the MGU-H right in 2017, not to mention Honda Jet sorting shaft balance issues out). I'm not suggesting "just any" designer would go for the idea, but someone designing the most advanced ICE-Hybrid units in history looking for every little gain.. absolutely. If he isn't looking at everything or experimenting and instead saying "no too hard", wrong job mate.

Electric car comment confuses me as there is zero need for them to do so.

[saviour stivala]

“The MGU-H must be solely mechanically linked to the pressure charging system. This mechanical link must be of fixed speed ratio to the exhaust turbine and may be clutched”.
The MGU-H being an electrical motor can of course be ‘decoupled’ electrically from the exhaust turbine, in which case the MGU-H electrically decoupled rotating part which is coupled to the exhaust turbine is still rotated by the exhaust turbine.
The advantage of having the MGU-H clutched to the exhaust turbine is the ability of eliminating the electrically decoupled rotating part from having to rotate with the exhaust turbine.
I believe that all four power unites employ a clutch between turbine and MGU-H because where there is an advantage nobody is going to skip-it.

[Bandit1216]

When waste-gate/s are open (party mode/free load mode) exhaust gasses are bypassing the turbine.

I mean harvesting in the corner/at breaking (that's why I first say "off throttle) and later on when you are on the strait you can use that energy in, what you call, free mode.

When waste-gates are open on the present F1 power unit the exhaust gasses are bypassing the exhaust turbine and not just Reliving the exhaust turbine of some of its pressure (regulating the pressure). Harvesting by the 'H'. There cannot be any harvesting by the 'H' when waste-gates are open because no work is being done by the exhaust gasses on the turbine which powers the 'H'.

Yes, and water is wet. Why are you trying to argue with someone that agrees with you? The harvesting I'm talking about is in the corner and/or at braking, when throttle and waste gates are closed. And unlike others who think they are always right, I'm just sharing a theory accepting I could be wrong.

[Jaisonas]

Had another random idea.

A while ago we were debating whether or not Honda had a clutch between the MGU-H and turbo (brought on by their class of the field performances at high altitude tracks) this is allowed by the regulations, we had decent reasons for both sides (complexity was one, even Renault said they wouldn't due to complexity), I still believe it's likely Honda do, even more so now with the onset of this anti-lag discussion. My main reason for believing in this clutch idea was the theoretical gain in compressor speed it allows. The turbo is not speed restricted but the MGU-H is restricted to 125,000rpm by the regulations, these two have to be geared 1:1 as well so it poses a hard limit on the turbo speed therefore maximum boost potential. So there was an argument Honda could decouple the MGU-H from the turbo at maximum power on straights to allow for an increase in turbine speed to compensate for the altitude deficit, it would also make sense as it seemed evident they may have gotten the mapping a little off sometimes, hence Max's mentioning of turbo lag out of some corners on occasion last year, that was the theory.

So now I am thinking.. why is this anti-lag sound/behaviour most prevalent during high power/quali laps since late last year and not really anything less than that (during sustained race modes, it is not present)? We are talking about it like it's primary use would be for energy recovery benefits and while it is possible, what I'm thinking, mainly because it's most obvious on fast laps, is what if this anti-lag is being used on high power modes as Honda have decoupled the MGU-H and are therefore free to run the turbo at as high an RPM as they want, no longer restricted to the 125,000rpm limit of the MGU-H. This anti-lag is a system which has become available to Honda with skip-fire use so are they using this to compensate for MGU-H motoring loss to sustain the turbo? Or is it to keep the turbine at a certain speed to recouple the H momentarily for power out of corners? Or would that even still be necessary if this is mapped correctly? Or a myriad of other things.

The work with Honda Jet, a lot of focus has been around the turbo from Honda, it's what they bring up all the time. I can't initially see why this is not a possibility for high power modes with the right engine and the right fuel allowing such high boost. Spec 4 and the special new fuel anyone?

This is a nice idea and all, but i dont think it can work in the split turbo design. If you were to clutch out the MGU-H, considering it sits between the turbo, you would disconnect the turbine from the compressor, basically shutting the turbo off. You would need a big-ass flywheel to maintain any momentum to the turbine when you were gonna clutch the compressor back in.

[saviour stivala]

“I don’t think it can work in split-turbo design. If you were to clutch-out the MGU-H, considering it sits between the turbo (compressor and turbine), you would disconnect the turbine from the compressor”.
“Sole single stage compressor linked to a sole single stage exhaust turbine by a shaft assembly, the shaft must be designed so as to ensure that the shaft assembly, the compressor and the turbine always rotate about a common axis and at the same angular velocity, an electrical motor generator (MGU-H) may be directly coupled to it”.
In the ‘split turbo system with the MGU-H sitting in between the compressor and the turbine both of which are mounted on a common shaft, the said compressor/turbine shaft is passing through the MGU-H ‘hollow’ shaft.