Honda Power Unit Hardware & Software

[godlameroso]

COTA has its surface ground down because the road surface itself becomes quite bumpy as the track settles. It'll need a repave soon.

[roon]

https://integralp.com/integral-e-drive/

There are quite a few other examples, I though the IP products were a bit special as the company was founded by Keith Duckworth's son together with other ex Cosworth people. Unsurprisingly, a few of their engineers moved to Mercedes a long while ago.

Interesting, thanks.

The cam covers and blocks have big buff ribs to take whatever load goes through the mounting points. Similarly, I think that the chassis side mounting can be easily designed to accommodate the thermal loads.

The obvious problem with a very compliant turbo/MGUH mounting is low natural frequency (vibration) and turbo twist under boost. The reason I brought up mounting is because unlike Merc, where the turbo sits very low, the Honda turbo sits quite high up and would need big old girders to mount to the block (bottom of the vee). That's why I though it's possible they might have mounted it to the heads or somewhere up the banks where relative thermal deformation is high (the LH and RH banks tend to come apart at temperature).

Someone brought up the bumpy nature of the circuit - I don't think this was a factor.
The shocks produced by hitting kerbs are significantly higher than those produced by track protuberances. I don't know how harsh kerbs are on COTA, but I can't recall drivers complaining about them.

Some thoughts:

-Are there CV joints or misalignment couplings which can operate at 100k RPM?
-If the shaft can slide axially as needed, and its bearings are encased within spherical carriers, this could accommodate some bending along the length of the shaft, or translation of the carriers.
-Perhaps Merc allow friction across the bearing surfaces during flex/distortion.

Andy Cowell notably said that the distribution of stresses through the engine block is the biggest factor on designing the split turbine housing. Did he say it took Mercedes maybe two years to solve or something?

Rule 5.1.6 comes to mind for me.

...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. The
shaft may not be mechanically linked to any other device.

I doubt they rigorously enforce that "the compressor and the turbine always rotate ... at the same
angular velocity." (If so, how?) By the wording, devices could be linked hydraulically or electromagnetically to the shaft.

[63l8qrrfy6]

Some thoughts:

-Are there CV joints or misalignment couplings which can operate at 100k RPM?
-If the shaft can slide axially as needed, and its bearings are encased within spherical carriers, this could accommodate some bending along the length of the shaft, or translation of the carriers.
-Perhaps Merc allow friction across the bearing surfaces during flex/distortion.

I doubt they rigorously enforce that "the compressor and the turbine always rotate ... at the same
angular velocity." (If so, how?) By the wording, devices could be linked hydraulically or electromagnetically to the shaft.

At that speed any misalignment in the CV joint would create catastrophic vibrations. Same goes for any significant shaft bending.

Any non-mechanical type of coupling that allows slip would cause losses and low efficiency.

[PlatinumZealot]

Normal shaft bending is not an issue. Let us get that off the table. There is no significan overhung load on the shaft. Even thermal loads at the hot end act purely radial in 360 degress at the same time.
Smaller scale bending due to vibration is there but remeber these shaft are balanced down the tiniest of tolerances. I would not expect any sigfinicant eccentricity in the center of mass of the shaft.

So i say forget about classical bending loads.

Did you guys botice that the Honda MGUH was more durable than the renault in the Mexico race? That rules out shaft length. And brings into the frame cooling as a significant factor.

[HPD]

Hasegawa: "I thought that the engine output would drop considerably, but in fact it was feeling that I was rather not falling down. Apart from the Mercedes AMG, I think that the fighting power was high here compared to Renault."
https://headlines.yahoo.co.jp/hl?a=2017 ... ports-moto

[restless]

Google translate gives different result:
"I thought that the engine output would drop considerably, but in fact it was rather a feeling that I was not falling down. Aside from the Mercedes AMG, the fighting power is here compared to Renault I think that it was expensive. "

Its obvious we can't understand from auto=translation what was really said, unless someone natively speaking Japanese helps

[etusch]

Google translate gives different result:
"I thought that the engine output would drop considerably, but in fact it was rather a feeling that I was not falling down. Aside from the Mercedes AMG, the fighting power is here compared to Renault I think that it was expensive. "

Its obvious we can't understand from auto=translation what was really said, unless someone natively speaking Japanese helps

Logicaly expensive is not the word belong there

[restless]

given the bizarre choice of words from the translator I don't think we have idea what was the meaning. At all.

[Craigy]

given the bizarre choice of words from the translator I don't think we have idea what was the meaning. At all.

Bing translate's version of this:

"I thought that the engine output would fall considerably, but in fact, it was a feeling that it was not likely to have fallen in the house rather. Apart from the Mercedes AMG, I think the fighting power here was higher compared to Renault. "

[godlameroso]

So they think they've closed the gap to Renault, perhaps the gap to Renault is similar to Renault's gap to Ferrari now?

[DFX]

So they think they've closed the gap to Renault, perhaps the gap to Renault is similar to Renault's gap to Ferrari now?

That's not what he has said at all. They fine tuned the PU for this race better than Renault, so in this conditions every PU had lost some power.. but let's say that Honda had lost 10hp less than Renault. That value has no basis, just as an example.

[HPD]

So they think they've closed the gap to Renault, perhaps the gap to Renault is similar to Renault's gap to Ferrari now?

That's not what he has said at all. They fine tuned the PU for this race better than Renault, so in this conditions every PU had lost some power.. but let's say that Honda had lost 10hp less than Renault. That value has no basis, just as an example.

Yes, as well as the friend @DXF says.

AMUS: In Mexico, the turbines have to turn higher to compensate for the power loss due to the thin altitude air. It was planned with an increase of 102 000 / min to 108 500 / min.

Honda did not turn the turbine higher. "However, we have found a way to compensate for the lost power by adjusting the engine," said Yusuke Hasegawa.

[HPD]

"The performance was much better than we thought," Hasegawa told Autosport.

"Before we came here, we thought our engine performance was worse than the other teams and the effect from the high altitude would be bad.

"But Sakura has worked hard to create a good set-up for this high altitude, which is why the engine power deficit was much smaller than we thought.

"This gap is smaller. The relative performance is still a bit behind, but we think we can catch up."

Hasegawa pointed to gains made on Honda's dynos at its Sakura base as a reason for its form in Mexico, where the high altitude puts a strain on the engines.

"Previously, we couldn't create a good dyno system to evaluate the high altitude situation," he said.

"But in the last week, we have made improvements in Sakura, regarding the operation of the engine. We made improvements here.

"[Correlation] is getting much better from the beginning of the season.

"It is not 100% copying the circuit situation, so still we need to work but we are almost satisfied with the situation.

https://www.autosport.com/f1/news/13276 ... erformance

[63l8qrrfy6]

So Honda scraped through by not increasing the turbo speed like everyone else. Regardless of what they say that must have been at the expense of quite a bit of performance and I think it indicates that they absolutely dread running the turbo faster due to resonances or instability issues.

Going back to the topic of potential bearing misalignment due to housing thermal deformation - in large industrial turbomachinery it is common to perform a catenary curve optimisation by intentionally misaligning the bearings so that they align under thermal and gravitational loads (rotors are so heavy that they distort the bearings significantly).
I haven't seen this applied to automotive turbochargers but maybe it is something worth exploring in F1 to alleviate thermal effects.

[Spud.Racer]

If see MGUH bearing issue as three part problem.

1. Gyroscopic angular momentum of the MGUH unit alone during a change of direction. How many Stone does the MGUH weigh?

2. Angular momentum from the turns being mounted high up in the engne V.

3. The engine deflection during a turn from the engine being used as a part of the chassis.

These must be calculated because the Dyno is not going to simulate this.

These are just my thoughts on this.