ME4ME wrote:j.yank wrote:You are making wrong assumption that all of this 70% time per lap on full throttle has available 120 kw even for the top teams. Various sources suggest that the total harvested power (both MGU-K and MGU-H) on Monza is around 4.2 MJ per lap. All teams struggle for energy there but obviously some more than the rest. If you make several scenarios where the deficit in McLaren case is coming from, and compare them to what we saw in the reality, you will see that MGU-H problem is not very convincing. The behavior of the McLaren cars in several situations speaks that probably they have a problem with harvesting of MGU-K rather than with MGU-H.
Where does that number come from? I very much doubt any PU manufacturer would state such thing publicly. My assumption that Mercedes and Ferrari are able to use the MGU-K in motor-mode basically always when on full throttle are merely based on observations; Blachimont as an example where the Mercedes car would still accelerate while the Mclaren wouldn't. I also wonder why, as you stated, Honda would have issues with MGU-K harvesting. It's limited to 2 MJ, so the other PU's are limited as well in this respect. It's not new technology either; even though the current MGU-K is more powerful, it's not that different from KERS which the teams have much experience of using. I guess because of the lack of some crucial information, inevitably wrong assumptions will be made. I'll happily admit to that.
Lets try to verify the 4.2 MJ per lap. Data from Brembo shows that around 0.7 MJ per lap can be harvested by the MGU-K during full braking, which seems very low but looking at pure braking time at 120 kW does not deliver that much energy. Lets assume that the MGU-K also generates a bit when the ICE delivers more power than the car can handle: 0.3 MJ, plus 0.7 from braking makes 1 MJ.
This means that 3.2 MJ per lap is generated by the MGU-H. Lets assume that the MGU-H is harvesting when the driver is on full throttle, it might be the case all the time but it is quite close imo. When we take a lap time of 1.25 at Monza and 70% of the track is full throttle, this results in 3.2MJ/(85*0.7)=54kW of MGU-H harvesting power, which is not a unreal value I think.
Edit: I just checked the link to Omnicorse in the post above me, in which the figure shows that around 2/9 of the total harvested energy comes from the MGU-K and 7/9(!) from the MGU-H. When we divide the 0.7 MJ from the Brembo data by 2/9, it results in 0.7/(2/9)=3.2 MJ, which I just assumed as the energy generated by the MGU-H.