Mercedes Power Unit Hardware & Software

[Maritimer]

Lets say ES mode with optimum boost delivers 5% power increase but can only be used 10 seconds per lap.

What if ES mode with reduced boost delivers 4% power increase but can be used 15 seconds per lap?

Which delivers the better lap time?

IIRC, in the Honda PU thread this was discussed and, with information released by Honda, it was clearly shown that "thick and short" is better than "thin and long".

So, once you are not traction limited is better to have 5% power increase during 10 seconds than 4% power increase during 15 seconds.

There is a difference. Honda are talking about the best way to distribute a given amount of energy. In the example I gave there is significantly more energy in the 4% power increase x 15 sec/lap.

Back when KERS was first being developed Honda found the same thing, better to use all the power in one lump than to try and spread it out over half the lap. Given the cars spend a good portion of a given lap already traction limited it doesnt make sense to worry about having an extra 5 seconds of deployment to use between corners, better to have ten second down the main straight(s) when you can actually put it down.

[subcritical71]

IIRC, in the Honda PU thread this was discussed and, with information released by Honda, it was clearly shown that "thick and short" is better than "thin and long".

So, once you are not traction limited is better to have 5% power increase during 10 seconds than 4% power increase during 15 seconds.

There is a difference. Honda are talking about the best way to distribute a given amount of energy. In the example I gave there is significantly more energy in the 4% power increase x 15 sec/lap.

Back when KERS was first being developed Honda found the same thing, better to use all the power in one lump than to try and spread it out over half the lap. Given the cars spend a good portion of a given lap already traction limited it doesnt make sense to worry about having an extra 5 seconds of deployment to use between corners, better to have ten second down the main straight(s) when you can actually put it down.

I think something is getting lost here. The Honda scenario was how best to deploy a fixed amount of energy either in stages or all at once. What gruntguru I believe is saying is that if you could get more energy in the second scenario (4% for 15 sec) would it then be wise to do it. Honda are saying how to deploy, for example, 2 J of energy in two different cases. Gruntguru is saying case one may be 2 J, but case two could be some value larger than 2 J. Would it then make sense to do the second scenario.

[Maritimer]

If you just think of peak output as a fixed amount, say 10 seconds of 1000hp or 15 of 985hp with an average nominal output of 970hp, id say it would still be best to go with the 10s of 1000hp on sections where the vehicle isnt traction limited.

While recovery and deployment arent fixed like they were with KERS it's safe to assume over an average race lap the energy available will be about the same, every lap. Works out more or less the same way.

[gruntguru]

It all depends on where the line sits - to give a less ambiguous scenario:

If your baseline power is 900 hp plus and you can have 950 for 10 seconds a lap or 945 for 20 seconds a lap, there is no way you would use your entire "allocation" at the 950 level (you might use some - at particularly beneficial points on the track).

The additional energy provided is 375 kJ at the higher output or 675 kJ at the lower.

[Just_a_fan]

If your baseline power is 900 hp plus you can have 950 for 10 seconds a lap or 945 for 20 seconds a lap, there is no way you would use your entire "allocation" at the 950 level (you might use some - at particularly beneficial points on the track).

Hence the drivers have "overtake buttons" to make use if everything they have to attack/defend, usually on the one straight each track has that allows overtaking.

[henry]

I don’t think it’s possible for anyone outside a select few in the PU teams to know the benefit or otherwise of offsetting crank power output against MGU-H power input. I think we can discuss the likely factors that come into play but the actual gains and losses in lap time we can’t know.

If a team thought there might be a benefit then they would need to run dyno tests to establish crank output and H power consumption for levels of boost. They would then need put this into track specific simulations to determine where the best lap time lies. They would probably need to include the effect of the exhaust mass flow on rear downforce and hence traction.

And as @Just_a_fan points out they might have a different mapping for overtake buttons.

Having raised the question of reducing boost with wastegates open I realised that some of the increased power comes from the pressure differential between intake and exhaust on intake. Does this make it less likely?

[gruntguru]

Having raised the question of reducing boost with wastegates open I realised that some of the increased power comes from the pressure differential between intake and exhaust on intake. Does this make it less likely?

Yes, IMHO.

[djones]

Last years Ferrari trick aside (which stopped after some rule clarifications), the Mercedes has always had the biggest boost in qualifying until this year.

I wonder if Mercedes sat on that advantage and spent all of their development on race characteristics. There is no denying they are generally the most solid team in race pace vs qualifying pace.

Halfway through the season and they are 150 points ahead of the nearest rival. So whatever they are doing in terms of deployment or development is clearly working well.

The talk of them needing "more power" as the rest are catching up and Ferrari is more powerful is panic for no reason IMO. Mercedes have the highest downforce and therefore most drag of any team, so of course, their straight-line speed will be compromised.

The PU is a package and its rating is not just power, but many other factors like reliability, fuel usage, race deployment, smoothness of delivery to protect the tyres etc. In that respect and in my humble opinion, the Mercedes is still comfortably ahead of any other team.

[dans79]

Mercedes have the highest downforce and therefore most drag of any team, so of course, their straight-line speed will be compromised.

This is the part that most people and even a lot of the press either don't understand, or just ignore.

[De Jokke]

Hmm, I don't think RBR has that much less downforce to be honest.
And Honda keeps on throwing updates. At this rate, Merc must be worried for next year if they don't come up with something radical for the engine (Ferrari is now way ahead and Honda almost on a par).

No way Ferrari will make the mistake of building another 'straightliner' for 2020.
And Honda will match merc in Monza (they claimed), so it must be very worrying for Andy Cowell and his team as they can only find small steps compared to the competition and if I'm not mistaken: this year's engine was a new layout already?

I don't know what feeling came over you but for me spec2 was a disappointment: almost no power boost compared to Fer and RBR's updates. Luckily they still have the advantage in the fuel economics, I think. But this will also be caught up sooner or later...

I read something about a new combustion method for next year's engine? Hopefully they have something radical going on which will propel them back to the top of the grid or atleast level with Ferrari. Also, I hope the energy spent in Formule E will pay off for the F1 team (improved knowledge of the ERS stuff etc.)

I really hope this team wins at least 8 titles. So close to the 6th but still many things can go wrong. A demotivated Bottas (if they would replace him by Ocon) bagging way less points than he could/should could be somekind of a revenge, you never know… It would be awesome to see Lewis ending this regulations period with 7titles under his belt and then at least winning one more in the new 'era' before he decides to call it quits. 10 titles would be awesome, but perhaps that a bit too much dreaming as the competition has closed the gap significantly…

First things first: securing these 6th titles!

[yelistener]

Mercedes have the highest downforce and therefore most drag of any team, so of course, their straight-line speed will be compromised.

This is the part that most people and even a lot of the press either don't understand, or just ignore.

Is that so, or it's just everyone recognizes it but also thinks the PU difference plays a bigger part, hence all the talk about the engine power?

[GPR-A]

Mercedes have the highest downforce and therefore most drag of any team, so of course, their straight-line speed will be compromised.

Is that so, or it's just everyone recognizes it but also thinks the PU difference plays a bigger part, hence all the talk about the engine power?

Pat Symonds, in his mid-year report on Autosport explains this well. Not sure how many people have autosport premium, not exactly worth, but once in a while there are good articles. Here is what he say.

Read full article at Autosport.com.
https://www.autosport.com/f1/feature/93 ... erm-report
A Small excerpt from the article.

But what of the challengers? Ferrari's pre-season form flattered to deceive. Its straightline speed was widely put down to an improved power unit, which perhaps even exceeded the performance of the long-dominant Mercedes engine.

In reality, acceleration data showed the two engines to be very evenly matched and the prodigious terminal speed of the Ferrari had more to do with lower drag than higher power.

The 5km/h difference seen in typical terminal speeds would have required a further 50bhp on a car with equal drag, but if we assume the power units to be equal it could also be achieved with around five points less drag.

Now, if we assume the two cars have equal aerodynamic efficiency then the five points of lower drag might equate to around 18 points less downforce, which in turn would show as a lap time deficit of around five or six tenths which, Bahrain excepted, is about what we are seeing.

[SSScoffee]

PGTech "Mercedes fired up its 2020 engine prototype which will be their biggest performance gain since 2014"

They're very, very reliable and always have inside info from both Ferrari and Mercedes.

https://twitter.com/SmilexTech/status/1 ... 0625012736

[roon]

Last years Ferrari trick aside (which stopped after some rule clarifications), the Mercedes has always had the biggest boost in qualifying until this year.

What was it?

[godlameroso]

Then it means all engines expect to be relatively even. If F1 wants parity then they themselves have to do track testing. Only the teams can fund that, but then one of them could get a huge advantage.

They should pool money into a design prototype that the FIA can test in public, make their findings public, and then let the teams develop that baseline. Granted this is a bit off topic.