2014-2020 Formula One 1.6l V6 turbo engine formula

[langwadt]

I told you all about the waste gate from the beginning but nooo.....

There is a fundamental difference with MGUH boost control and a waste gate. One is a load and one is a bypass.
If the MGUH is going to load the turbine to control speed, that kinetic energy is going to change to heat energy, and this is where their heat sink came in apparently; in the case where the battery cannot hold this energy. And even if it does hold this energy, the inefficiencies of the charging will produce a lot of heat.
It is my opinion that Renault got to greedy with harvesting, to the point that there was a lot of heat generated as the back pressure increased.
Just put a waste gate and let it out, you can't capture everything. There is a thermodynamic law relating to what is called "availability" but I can't bother get into that right now.

Yes, it looks like you were right that eliminating the wastegate is more difficult than some here thought, and maybe 'Renault got to greedy with harvesting' too soon. But I disagree than anyone will remain competitive long term if they do not harvest as much energy as is possible.
snip

thinking out loud here: could it be that the MGU-H boost control works just fine in theory and on the bench with a nice smooth application of power, but in reality the when driver modulates the accelerator more aggressively on-off (wheel spin?) it doesn't add up anymore. When he lets of the accelerator the boost peaks up but they can't dump power it in the
MGU-K because the torque request is low and the ES might be full, seems they anticipated this with the resistor dump
but maybe it is just a lot worse than they thought?

still whether with resistors or with a wastegate it sounds wrong to dump energy in a formula that is revolves around efficiency

[wuzak]

@wuzak : Thanx a lot man for enlighten me with these things!
1.

The MGU-H could supply 10MJ to the system - if the turbine could provide enough power.

a)Why the turbine couldn`t provide enough power?
b)There are mandatory turbine dimensions/size? coz I didn`t find anything regarding this matter in the rules …

It is the limits of the system. They could extract more power, but that would affect the power of the engine and could reduce efficiency.

There are no mandatory turbine dimension sizes, only that it can only be a single stage turbine.

2.

The MGU-K won't be recovering 2MJ per lap on most circuits - at least not from braking.

a)Why can`t MGU-K provide 2MJ per lap?
Coz to cope with 4MJ/lap this year isn`t MGU-K electric generator capability in the same amount with the electrical motor?
From The Renault Energy F1 release technical sheet : “The MGU-K is connected to the crankshaft of the internal combustion engine and is capable of RECOVERING or PROVIDING power (limited to 120 kW or 160 bhp by the rules).”
b) Could MGU-K recover other energy than braking? Your sure it`s not solely from braking?
c) Last year they could recover energy solely from rear brakes, right? This year could they recover even at the front one?

The 2MJ limit has been answered.

The MGU-K can, theoretically, generate by adding a drag on the ICE, reducing the power to the wheels and storing the energy for later use.

3.

No, the use of the MGU-H to power the MGU-K is not dependent on the ES.

Yeah I know that but was poor in explain it So I know they could “split” the power for ES and for MGU-K ...

Yes.

4.

It is unlikely that much of the MGU-H energy recovered will be sent to the ES.

a) Are you sure of that? I`m afraid it`s the other way around coz as I understand the MGU-H first priority is to harvest the ES with the remaining 2MJ/lap that MGU-K can`t do it due to the rules and in the end to reach the 4MJ/lap limit in order to get the max. power allowed for the latter …
b) Then what`s the reason behind the imposed rule for max. 4MJ/lap for ES?

Most of the time when the MGU-H will be harvesting will be when maximum or near maximum power is demanded. By routing the power from the MGU-H you lose energy through additional inefficiencies.

Not sure why the 4MJ rule was imposed. I suppose it enables some strategy play, where the ES isn't used to power the MGU-K for a few laps, while braking energy is stored. This then allows extra power for an attempt at overtaking (or at a fastest lap for someone like Seb).

5.

And basically any time the engine is at full throttle the MGU-H will be sending energy to the MGU-K.

a) So what you are saying here is that, let`s say, from a 90 sec. lap a driver has 33,3 sec available to release the max. power – 120KW – provided by MGU-K (the max. power mapping scenario) and for the remaining 56,7 sec he could use what power MGU-H is sending to MGU-K ?
b) What power delivers this MGU-H, in general, we don`t know (but we could assume which amount it has, isn`t it?) and manufacturers has a free liberty regarding this matter, right?
c) And if it`s free to develop it then until when they have this liberty? or when MGU-H it`ll become a “frozen” spec?

a) on a track like Monza, with roughly an 85s lap, the MGU-H will probably be sending power to the MGU-K for 70s or more.

It is best to look at it the other way. If the MGU-H can supply 60kW of power, the ES only needs to supply 60kW of power. Thus the 4MJ limit will last 67s.

b) We don't have a certain idea of what power the MGU-H will deliver.

However, there have been some graphs produced by Cosworth that indicate that the MGU-H provides ~110hp @ 12,000rpm (ICE) and up to 120hp towards 15,000rpm (but over all power is reduced). Useful power is generated by the MGU-H over ~8,000rpm.

c) Development is restricted. Generally, though, the aim is to improve efficiency, and this is one area that can help to deliver that.

Also, the long term plan for these rules is that the fuel flow limit will be reduced. The electrical power side of this should, therefore, be increased o compensate for power loss of the ICE.

6.

Some energy will be sent from the MGU-H to the ES, if only to be later used for spooling up the turbo.

So what you are implying is that they`d never use 4MJ/lap from ES solely for MGU-K coz they need energy for MGU-H in order to decrease turbo lag?

There is no limit as to the energy transfer between the ES and the MGU-H. The only limiting factor is the maximum storage of the ES, which is also 4MJ. My understanding of that is that you can transfer any amount in or out, so long as there is no more than 4MJ stored at any one time.

The other limit, 4MJ, applies only to transfer from the ES to the MGU-K.

7.

The MGU-H is linked via a fixed gearing ratio and clutch to the turbo

a) Where in the rules states which gearing size is mandatory?
b) Or they have freedom with it?
c) In this case why not have the same speed like ICE?

Gearing is not mandatory, but since the turbo is allowed to spin at 125,00rpm it is probably advisable.

The regulations specify:
5.2.4 The MGU-H must be solely mechanically linked to the exhaust turbine of a pressure charging system. This mechanical link must be of fixed speed ratio to the exhaust turbine and may be clutched.

[wuzak]

Re the H to K transfer
There are times when you can't (or wouldn't want to) transfer power from the H to the K but still need to limit turbo speed.

Think along the lines of a short burst of acceleration then slight deceleration then acceleration (such as feathering throttle for traction or in a switch back). The last thing the driver would want is for the K to feed power into driveline.

During those transitional situations Renault wanted to control the speed of the turbo by using the H to maintain shaft speed at or close to max rpm. It turned out (partly because of the driveability issues) that H was dumping to the heat sink far more than had been predicted or modelled. This was causing severe heat related issues in some cars at Jerez and the Renault 'patch' was to disable the H entirely and rely on the mechanical wastegate for the remainder of the test.

Obviously this resulted in dramatically increased lag and reduced performance but allowed some mileage to be put on the ICE.

I would have thought that the engine mapping would allow for this situation, in that when the driver demands power the computer decides ho much is required by the ICE and by the MGU-K. If at some point the driver wants 600hp, this can be delivered by the ICE alone using the 100kg/h fuel flow limit. But it could equally be achieved by reducing the fuel flow and using the MGU-K to add the extra power up to the required power delivery. Thus you could save fuel.

[OO7]

Thinking about the use of the MGU-H, perhaps this (in addition to the increased torque) explains why there are quite a few comments on just how powerful these power units are. If they are able to get 650bhp from the ICE and 110bhp from the MGU-H, that is already 760bhp with no time constraints. In 2013 the additional 80bhp from KERS was only available for 6.67 seconds, whereas now an additional 50bhp from the ES to the MGU-K will be available for so much longer.

[ringo]

Yes, it looks like you were right that eliminating the wastegate is more difficult than some here thought, and maybe 'Renault got to greedy with harvesting' too soon. But I disagree than anyone will remain competitive long term if they do not harvest as much energy as is possible.

Renault has apparently replaced their battery supplier; maybe the energy store was not meeting its spec for accepting power. There is no FIA rule or fundamental physical limit to the rate the energy store can accept energy from the MGU-H. How does the 'thermodynamic law relating to what is called "availability" ' have any impact on this?

If they figure out how to ensure there is always a flow of energy from the MGUH then they will have a formidable power unit.

I find this interesting, as in order to control the boost with the mguh, there must be a load added to the compressor load that equals the available power of the turbine. This must be constantly monitored as the air requirements and thus compressor demand changes.
Now the battery charging system may have to serve as this load. If the charging rate can be varied continuously to whatever would allow a balance for a specific turbine speed then you have yourself a boost control system. Notwithstanding, it must also have some form of temporary energy storage (capacitor) or flow path (MGUK) when the battery is full. There can't be a retarding load load if the current can't flow.

So it gets very tricky when there is nowhere to put that energy. Hence the heat sink; which to me is silly, since it's better to put that heat out a waste gate in the first place.
What Renault may have to do if this is to work is to ensure that the battery is never full, and that the charging rate is always higher than the excess power from the turbine. This would require MGUK to be constantly engaged to keep the energy flow. Sounds good in theory.. But what if you don't want MGUK all the time? maybe the torque is too much in low speed corners, what do you do with the MGUH retarding energy?
You could burn up your electronics with it maybe. Maybe use the heat sink to power some thermoelectrics.

All the above to me is too much to consider when a little flapper valve can just dump it away and simply the problems. No need to try save every last drop of energy. Just make a fast car that can do the race with less than 100kg of fuel and be done with it.

[mrluke]

I find this interesting, as in order to control the boost with the mguh, there must be a load added to the compressor load that equals the available power of the turbine. This must be constantly monitored as the air requirements and thus compressor demand changes.
Now the battery charging system may have to serve as this load. If the charging rate can be varied continuously to whatever would allow a balance for a specific turbine speed then you have yourself a boost control system. Notwithstanding, it must also have some form of temporary energy storage (capacitor) or flow path (MGUK) when the battery is full. There can't be a retarding load load if the current can't flow.

So it gets very tricky when there is nowhere to put that energy. Hence the heat sink; which to me is silly, since it's better to put that heat out a waste gate in the first place.
What Renault may have to do if this is to work is to ensure that the battery is never full, and that the charging rate is always higher than the excess power from the turbine. This would require MGUK to be constantly engaged to keep the energy flow. Sounds good in theory.. But what if you don't want MGUK all the time? maybe the torque is too much in low speed corners, what do you do with the MGUH retarding energy?
You could burn up your electronics with it maybe. Maybe use the heat sink to power some thermoelectrics.

All the above to me is too much to consider when a little flapper valve can just dump it away and simply the problems. No need to try save every last drop of energy. Just make a fast car that can do the race with less than 100kg of fuel and be done with it.

Agreed.

[WhiteBlue]

I told you all about the waste gate from the beginning but nooo.....

There is a fundamental difference with MGUH boost control and a waste gate. One is a load and one is a bypass.
If the MGUH is going to load the turbine to control speed, that kinetic energy is going to change to heat energy, and this is where their heat sink came in apparently; in the case where the battery cannot hold this energy. And even if it does hold this energy, the inefficiencies of the charging will produce a lot of heat.
It is my opinion that Renault got to greedy with harvesting, to the point that there was a lot of heat generated as the back pressure increased.
Just put a waste gate and let it out, you can't capture everything. There is a thermodynamic law relating to what is called "availability" but I can't bother get into that right now.

Well, we told you all about it as well. Renault simply do not have the know how of the recovery system that Ferrari and Mercedes have. In order to get maximum efficiency you have to utilize the waste gate close to zero. The other manuafcturers have mastered that problem which Renault are still in the process of cracking.

[dren]

Renault either underestimated the energy flow into the ES, or the demand of flow out of the ES, or a bit of both. There should never be a situation where the ES is full and there is regeneration going on unless there was some sort of failure. A wastegate should be utilized as a safety only, not as a controller.

There should be an energy level graph for the ES over a lap at each track. It would involve flow in and out from both MGUH and MGUK at each point over the lap. This would be part of the need for PU mapping at each race. Renault must have screwed up somewhere and likely were running really close to the ES limit of storage, hence the need for the resistors. Maybe the battery type and or capacity limit was part of the issue, too. Didn't they say they switched suppliers?

Maybe it is easier to just dump the energy in the quick off throttle stages and only charge the ES on high RPM turbine overrun.

[pgfpro]

I told you all about the waste gate from the beginning but nooo.....

There is a fundamental difference with MGUH boost control and a waste gate. One is a load and one is a bypass.
If the MGUH is going to load the turbine to control speed, that kinetic energy is going to change to heat energy, and this is where their heat sink came in apparently; in the case where the battery cannot hold this energy. And even if it does hold this energy, the inefficiencies of the charging will produce a lot of heat.
It is my opinion that Renault got to greedy with harvesting, to the point that there was a lot of heat generated as the back pressure increased.
Just put a waste gate and let it out, you can't capture everything. There is a thermodynamic law relating to what is called "availability" but I can't bother get into that right now.

Well, we told you all about it as well. Renault simply do not have the know how of the recovery system that Ferrari and Mercedes have. In order to get maximum efficiency you have to utilize the waste gate close to zero. The other manufacturers have mastered that problem which Renault are still in the process of cracking.

WB I have to agree with you on this one. I think RB pick to small of a turbine on their turbo.

At low rpm coming out of a corner running larger turbine, "after a long straight with battery full" the MGUH motor mode will spool the turbo to the correct boost level based on fuel limits. At this point I modeled a larger turbine being used then conventional thinking and no MGUH generator mode electricity would be made until just a hair below 9000 rpm because all exhaust will have to pass through the turbine with no load put on it from the MGUH. This will give the correct amount of compressor air flow to the engine.

Then from 9000 rpm up you start bringing in the K combine with the ICE. Also on switch backs just short shift the the car to make sure your running on ICE only with no power MGUH power back to the battery's.

The other thing I can't understand is why is the battery full or close to full??? IMO I would being using the MGUK on all the straights to accelerate the car as fast as possible. So in the first stages of road testing pull as much power out of the battery pack as you can then start mapping power down depending on the track to make sure you have enough battery power for maximum efficiency.

EDIT:

dren My thoughts exactly!! My third paragraph. You did a better at explaining it.

[OO7]

Renault either underestimated the energy flow into the ES, or the demand of flow out of the ES, or a bit of both. There should never be a situation where the ES is full and there is regeneration going on unless there was some sort of failure. A wastegate should be utilized as a safety only, not as a controller.

Correct me if I'm wrong but didn't Renault's own press release of their new power unit state that the waste gate was purely a safety device?

[mrluke]

That all works fine for your theoretical flying lap but it becomes complicated when you get down to the detail, for instance very short duration high throttle openings, where the driver is feathering the throttle.

If the driver is having lots of wheelspin (or perhaps doing donuts after the finish of the race ) where does the huge excess mgu-h power go? The ES has a finite capacity so that isnt going to work, you could send it to the MGU-k but this only serve to increase wheel spin. While this might be desirable for deliberate donuts it is clearly not the way you want to programme your ecu for racing.

What happens in the rain? The usual way to turn the boost down is to open the wastegate more, however current proposal will be to absorb more energy via the MGU-h.....how are you going to use or store this?

[langwadt]

That all works fine for your theoretical flying lap but it becomes complicated when you get down to the detail, for instance very short duration high throttle openings, where the driver is feathering the throttle.

If the driver is having lots of wheelspin (or perhaps doing donuts after the finish of the race ) where does the huge excess mgu-h power go? The ES has a finite capacity so that isnt going to work, you could send it to the MGU-k but this only serve to increase wheel spin. While this might be desirable for deliberate donuts it is clearly not the way you want to programme your ecu for racing.

What happens in the rain? The usual way to turn the boost down is to open the wastegate more, however current proposal will be to absorb more energy via the MGU-h.....how are you going to use or store this?

if you don't need the power in the rain you make less power with the ICE thus less power with the MGU-H
I think it is a transient problem, they can't just slam the throttle on and off, they have to be smooth else they'll
constantly have excess MGU-H power with no where to go

[dren]

That all works fine for your theoretical flying lap but it becomes complicated when you get down to the detail, for instance very short duration high throttle openings, where the driver is feathering the throttle.

If the driver is having lots of wheelspin (or perhaps doing donuts after the finish of the race ) where does the huge excess mgu-h power go? The ES has a finite capacity so that isnt going to work, you could send it to the MGU-k but this only serve to increase wheel spin. While this might be desirable for deliberate donuts it is clearly not the way you want to programme your ecu for racing.

Huge wheelspin would be an issue of pedal mapping, ecu mapping, and gear selection. The PU still has to put out torque based on pedal demand.

As for turbine overspeed control off throttle, you dump it to the ES. If the MGUH is sending 120hp or so to the MGUK and then the torque demand goes to 0, that 120hp will be sent to the ES but it will quickly drop since fuel is cut and for the need to keep the turbo spooled.

They should calculate energy use and flows and should never max out the ES. Over a lap the car will use ES for the MGUH to spool the turbo and to add to the MGUK. Renault got their calculations wrong somewhere and may have sized the turbine wrong as pgfpro stated above.

@pgfrpo - Autosport Live update feed was reporting Mercedes cars short shifting quickly on acceleration out of corners. This falls in line with your thoughts. Although the Ferraris were holding gears much longer.

If you take regenerative braking completely out of the picture, I find it hard to believe that you would charge the ES more with excess MGUH in these situations than you would pull from the ES to supliment the MGUK during max power demand.

[PhilS13]

Silly question maybe but I can't find the answer...

2013 V8 @ 30% efficiency and 750 bhp peak power -> 1750 "bhp" of heat generated (waste). Yes only at peak power operation but still.

2014 V6 @ 40% efficiency (self-sustained), 100 kg/hr fuel limit, 46MJ/kg fuel -> 1028 "bhp" of heat generated (waste)

We keep hearing the V6 needs massive cooling relative to last year. Where does that come from ?

[OO7]

Silly question maybe but I can't find the answer...

2013 V8 @ 30% efficiency and 750 bhp peak power -> 1750 "bhp" of heat generated (waste). Yes only at peak power operation but still.

2014 V6 @ 40% efficiency (self-sustained), 100 kg/hr fuel limit, 46MJ/kg fuel -> 1028 "bhp" of heat generated (waste)

We keep hearing the V6 needs massive cooling relative to last year. Where does that come from ?

Turbo cooling, intercooling, ES cooling, MGU-H cooling, MGU-K cooling etc.