Honda Power Unit Hardware & Software

[Wazari]

What i understand, is that Honda aimed for a compact, very high reving turbocharger. But got a lot of trouble overheating this turbo, so i needs limit the turbo's rpm. Now the target pressure, flow and harvesting, aren't achieved. On top of that, stressing the turbo for to long, will cause failure, so drivers are instructed to drive calm.

I think you hit the nail right on the head. I think Honda overestimated how much heat they could bleed off in the "size 0" bodywork constrictions. The speed of the shaft to the MGU-H unit in generating mode I believe was well below target.

The other issue I think they ran into was underestimating velocity loss in the induction plumbing. I looked up close at the turbo plumbing at Suzuka and thought to myself, there has to be a better way to place the intercoolers and get the air faster back into the plenum. But hey, what do I know.....

[Abarth]

Regarding VGT, it has advantages when there is a wide range of exhaust gas mass flow that must be used efficiently.
In this formula, engines are working most of the time in a pretty small range, and transients can be handled by MGU-H.
I don't think VTG would bring any advantages, and adds mostly complexity.

[Joseki]

What i understand, is that Honda aimed for a compact, very high reving turbocharger. But got a lot of trouble overheating this turbo, so i needs limit the turbo's rpm. Now the target pressure, flow and harvesting, aren't achieved. On top of that, stressing the turbo for to long, will cause failure, so drivers are instructed to drive calm.

I think you hit the nail right on the head. I think Honda overestimated how much heat they could bleed off in the "size 0" bodywork constrictions. The speed of the shaft to the MGU-H unit in generating mode I believe was well below target.

The other issue I think they ran into was underestimating velocity loss in the induction plumbing. I looked up close at the turbo plumbing at Suzuka and thought to myself, there has to be a better way to place the intercoolers and get the air faster back into the plenum. But hey, what do I know.....

You mentioned how much heat they can handle with the Size 0 concept as a problem, and I was wondering if having a air-air intercooler instead of a air to water one like Mercedes and Ferrari was part of this problem.

I think now it's crucial for McLaren to continue with the size 0 concept for 2016.

[GoranF1]

What i understand, is that Honda aimed for a compact, very high reving turbocharger. But got a lot of trouble overheating this turbo, so i needs limit the turbo's rpm. Now the target pressure, flow and harvesting, aren't achieved. On top of that, stressing the turbo for to long, will cause failure, so drivers are instructed to drive calm.

I think you hit the nail right on the head. I think Honda overestimated how much heat they could bleed off in the "size 0" bodywork constrictions. The speed of the shaft to the MGU-H unit in generating mode I believe was well below target.

The other issue I think they ran into was underestimating velocity loss in the induction plumbing. I looked up close at the turbo plumbing at Suzuka and thought to myself, there has to be a better way to place the intercoolers and get the air faster back into the plenum. But hey, what do I know.....

there were 2 major problems
1. overheating of compressor and everything local to him
2. terrible vibrations by TC when spining at 120k RPM

A quote from a source simillar to "the nephew"

It all starts with the "size 0" body that the designers wanted at the back end of the car. The extra-narrow pinch at the back would have certain aero advantages: better downforce directly over the rear axle, better rear grip, less drag, and so on.
Problem: this means less space for the engine. In particular, there wasn't a good spot to put the compressor for the turbo.
Solution: they'll fit the compressor right into the "V" of the engine, instead of ahead or behind.
Another problem: that's a pretty small space to begin with. A normal compressor wouldn't fit there. You could squeeze in a small one, though.
Another solution: since it'll be smaller, the compressor will have to cycle faster to deliver the same power. About 130,000rpm instead of the more typical 110-120krpm. Most other teams aren't sure they could even make a (normal sized) compressor cycle faster than 120k without blowing up -- if they could get more power they'd already be running them faster. But Honda are confident that they can make a smaller one go that fast.
Season starts. To everyone's surprise, the small compressor does go that fast, without blowing up.
But, it has extreme, violent vibrations at max speed. Connections get shaken loose. When they are attached more securely, they get snapped and broken from the thrashing. Honda redesigns the connections.
Next problem is the compressor gets too hot. Unexpectedly hot. It's frying the nearby connections and electronics with heat. Honda tries to fix this, add cooling or insulate the rest somehow.
They don't find a way to completely fix the thermal issues (it's not exactly easy trying to route cooling airflow through the middle of your engine), and ultimately the only solution is to turn down the compressor so it doesn't get as hot.
Problem: with the compressor turned down so far, the ICE is losing a lot of power. Like 60-80bhp at least. At the lower power level, there's less heat created exhaust power available for the MGU-H to collect, meaning a further loss of power -- the hybrid batteries don't get fully charged, and so on. The losses just cascade and multiply through the entire power plant.
Honda spends the rest of the season making incremental efficiency improvements to the ICE (making the most of what they get from the turned-down compressor) and riding the edge of how high they can run the compressor before ruining the works. They squeeze out many tens of additional BHP but it's nowhere near enough to make up for the shortfall.
Most sessions cost them an engine but they do manage to get a couple of them through entire races, always at the back of the midfield because of the compromised power levels.

[Wazari]

What i understand, is that Honda aimed for a compact, very high reving turbocharger. But got a lot of trouble overheating this turbo, so i needs limit the turbo's rpm. Now the target pressure, flow and harvesting, aren't achieved. On top of that, stressing the turbo for to long, will cause failure, so drivers are instructed to drive calm.

I think you hit the nail right on the head. I think Honda overestimated how much heat they could bleed off in the "size 0" bodywork constrictions. The speed of the shaft to the MGU-H unit in generating mode I believe was well below target.

The other issue I think they ran into was underestimating velocity loss in the induction plumbing. I looked up close at the turbo plumbing at Suzuka and thought to myself, there has to be a better way to place the intercoolers and get the air faster back into the plenum. But hey, what do I know.....

You mentioned how much heat they can handle with the Size 0 concept as a problem, and I was wondering if having a air-air intercooler instead of a air to water one like Mercedes and Ferrari was part of this problem.

I think now it's crucial for McLaren to continue with the size 0 concept for 2016.

Well typically air to water intercoolers are more efficient than air to air but they again they require more plumbing and space. However, Honda's main issue IMO is not the temp of the incoming charged air but dissipating the heat coming off the turbo components.

Goran's post above IMO does an excellent job of summing up Honda's issues. Do you mind Goran-san sharing where you received that information.

[FW17]

^

May be http://www.motorsportmagazine.com/f1/ex ... into-2016/ or https://www.reddit.com/r/formula1/comme ... community/

[KingHamilton01]

reading the post above doesn't fill me with confidence unless engineer's at McLaren have said to Honda they need to fundamentally change there approach to certain components and change the Engine layout. This would certainly go with the fact McLaren say they are frustrated because Honda being stubborn to against there original layout and design. Let's hope they do find a balance and get on top of ERS and ICE they certainly cannot afford a winter like last year's.

Got to have a solid foundation in which to build there season from early on, otherwise 2017 will turn into the main focus. Which to be honest imo will be there best chance to mount a comeback depending on what technology and how much of a head start Mercedes have had with 2017 spec engine.

[Brian Coat]

reading the post above doesn't fill me with confidence unless engineer's at McLaren have said to Honda they need to fundamentally change there approach to certain components and change the Engine layout. This would certainly go with the fact McLaren say they are frustrated because Honda being stubborn to against there original layout and design. Let's hope they do find a balance and get on top of ERS and ICE they certainly cannot afford a winter like last year's.

Got to have a solid foundation in which to build there season from early on, otherwise 2017 will turn into the main focus. Which to be honest imo will be there best chance to mount a comeback depending on what technology and how much of a head start Mercedes have had with 2017 spec engine.

Hi,

McLaren formed a partnership with a world class power unit engineering company (which McLaren never pretended to be) so I doubt they'll be giving Honda much advice on the "... approach to certain components ...".

They will be expecting Honda to deliver of course.

I doubt that there is much pressure that McLaren could apply which is not exceeded by the internal pressure at HRD.

Imagine - you work for a proud company which has been scoring GP points on and off since 50 years ago with several world titles under its belt. You have been hand-picked to write the next chapter of the illustrious Honda Racing legend and you find yourselves under the spotlight with a problem like this.

For the engineers in the thick of it, 'character-building' probably doesn't begin to describe it.

[GoranF1]

^

May be http://www.motorsportmagazine.com/f1/ex ... into-2016/ or https://www.reddit.com/r/formula1/comme ... community/

Yes,a known user on reddit.

[trinidefender]

^

May be http://www.motorsportmagazine.com/f1/ex ... into-2016/ or https://www.reddit.com/r/formula1/comme ... community/

Yes,a known user on reddit.

The same user also says this though "I have no inside info, this is all just gleaned from articles over the season." It appears he has just been doing the same thing we have all season.

[mrluke]

On the other hand if he identifies himself as a current honda engineer that would undoubtedly be in breach of NDA or similar.

[trinidefender]

On the other hand if he identifies himself as a current honda engineer that would undoubtedly be in breach of NDA or similar.

Yea so what. Of course that would probably be a breach of an NDA. Doesn't make him seem any more like a Honda engineer though.

By that logic, if he said this to trick us so he must be a Honda engineer then we are all insiders and that Wazari is really Arai. This give me a chuckle.

[GoranF1]

On the other hand if he identifies himself as a current honda engineer that would undoubtedly be in breach of NDA or similar.

Yea so what. Of course that would probably be a breach of an NDA. Doesn't make him seem any more like a Honda engineer though.

By the logic of he said this to trick us so he must be a Honda engineer then we are all insiders and that Wazari is really Arai. This give me a chuckle.

Wazari speaks to good English to be Arai.

Regarding the reddit user,he is most likely not an insider but it does sound logical what he says no?

[NL_Fer]

But i still keep wondering. Ferrari in 2014 admitted, they compromised the turbo size and exhaust harvesting, for a more compact engine, to allow better aero. Chassis department tried to gain the speed lost, by the pu department, with mor downforce. They failed.

So did Honda another way, design a compact pu, which does deliver the maximum performance? Or did they copy Ferrari's strategy, set a lower target, to be able to design a smaller pu. And did they result in a compromised design, which on top of that, didn't even reach the (lower) targets?

[Wazari]

I am definitely not Arai-san. I am old enough to be his father.