Honda Power Unit Hardware & Software

[NL_Fer]

Wazari, can you help me with this question?

Was the original PU design ever able to run a full lap of deployment? Did they choose to have less harvesting for a smaller pu, or was the ERS problem all caused by the turbo/mgu-h not working as designed?

[DarkAlman]

Correct me if I'm wrong here, but a smaller turbine means they have to run the turbo compressor at higher RPM to maintain boost. Higher speed means less torque so less energy that can be harvested by the MGU-K and harder to spin back up on the reverse side no?

[gruntguru]

No. Energy rate = torque x speed. So less torque x more speed = similar energy flow.

[Wazari]

Wazari, can you help me with this question?

Was the original PU design ever able to run a full lap of deployment? Did they choose to have less harvesting for a smaller pu, or was the ERS problem all caused by the turbo/mgu-h not working as designed?

Hmmm. I can't say too much except yes the MGU-H unit failed to meet expectations and yes at AD they did run at full deployment for at least one lap.

[mclaren111]

I hope this true. Getting bored with all Merc powered cars in the front. Also want to make the sponsors which decided to leave Mclaren regret.

I like your thinking =D> =D>

[FW17]

Wazari

From your personal experience with Turbocharged engines what is the line of thinking in the various projects you have worked with regard to the sizing of turbine and compressor.
What are essential for the turbine to generate maximum shaft power?
What are the pros and cons of small and large compressor in using shaft power?
Would MGU-H been always on generator mode of a VGT was allowed?

[hemichromis]

Arai has said the the compressor next year will be "probably about the same size more or less as Mercedes"
but still in the V.

Sounds good to me!

I will choose to remember the year by the Abui dhabi tire test!!

[GoranF1]

Arai has said the the compressor next year will be "probably about the same size more or less as Mercedes"
but still in the V.

Sounds good to me!

I will choose to remember the year by the Abui dhabi tire test!!

I will remeber it by that one 1,44,??? lap Honda gave Alonso full deployment in Abu Dhabi race.

[Postmoe]

Alonso said at the BBC that Honda made some "big changes" after the infamous "GP2 engine" team radio in Japan. He also said that he felt like this helped the team to focus more on what was needed to improve.

I think maybe Mr. Alonso might think too much of his comments. I don't think what Alonso said during the race had any bearing on the team's focus. The changes were already in the pipeline regardless of Alonso's comments. The only comments the Honda engineers pay attention to are from the race director and sometimes the drivers in designated staff meetings.

Actually was just some clickbait from BBCF1:

Formula 1: Fernando Alonso says public criticism helped Honda focus
Fernando Alonso says his criticisms of McLaren's Honda engine over team radio helped focus the company on the need to make drastic changes.

What Alonso said is:

"The actions we need to take next year to be competitive [are] quite extreme, for big problems you need big solutions, and I think maybe that helped a bit for the big solutions."



http://www.bbc.com/sport/formula1/35007148

He is basically saying that he was being Mclaren's way to put public pressure on Honda.

[PlatinumZealot]

He definitely knows what he is doing. Sometimes engineers need a swift kick up the backside to get their thinking straight.
A driver who doesn't complain either doesn't want any better rs is secretly planning to switch teams; so good on Alonso for that outburst.

[j.yank]

Hmmm. I can't say too much except yes the MGU-H unit failed to meet expectations and yes at AD they did run at full deployment for at least one lap.

What about Canada when Vetel wasn't able to pass him for two laps even with DRS? It was exactly the time when Alonso wanted over the radio to leave him to race without restrictions.

[godlameroso]

Hmmm. I can't say too much except yes the MGU-H unit failed to meet expectations and yes at AD they did run at full deployment for at least one lap.

What about Canada when Vetel wasn't able to pass him for two laps even with DRS? It was exactly the time when Alonso wanted over the radio to leave him to race without restrictions.

It goes to show how difficult a task it is. I'm sure the power unit is very good in bursts, but longevity is the key. I guess part of the problem is building an engine strong enough to take the abuse, not just one about having an engine being able to make power. The structures in the block are something no one ever even remotely mentions, because all everyone is concerned with is absolute power numbers and not usable power numbers. McLaren has been guided away from chasing peak numbers aerodynamically and instead focus in maximum usable downforce, it's paid off for them, the engine needs to follow suit.

One advantage of casting an engine as oppose to pure milling is that you can create parts of the block to have reinforced areas, but sometimes while being strong can increase the likelyhood of hot spots. Something like this would require a rework of certain areas of the block and these changes would be very costly token wise.

[NL_Fer]

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.

[Wazari]

Wazari

From your personal experience with Turbocharged engines what is the line of thinking in the various projects you have worked with regard to the sizing of turbine and compressor.
What are essential for the turbine to generate maximum shaft power?
What are the pros and cons of small and large compressor in using shaft power?
Would MGU-H been always on generator mode of a VGT was allowed?

Let's see, where to start. First off, when I was working with turbochargers for F1, things were much simpler. We didn't have this thing called a MGU-H attached to the turbo to act as a generator and motor. The overall theory seems simple enough on paper but when I start thinking about the actual application in a race engine with fuel flow restrictions, well it gives me a headache.

Turbocharging efficiency has many, many variables. In the very simplest of terms, not factoring cost and the MGU-H unit, it's a balancing act. How much exhaust gas are we working with, how much forced induction do we want to push into the combustion chamber, how much are we going to lose due to plumbing, etc. All these factors are weighed into the actual design of the turbo desired for that application.

When you mention the turbine generating maximum shaft power, are you talking about torque to the compressor or the compressor speed? Again in simple terms, you need to look at how much exhaust volume and velocity you're working with. People mention size of the turbine or compressor but there is much more than that. I think people are associating the radius of the actual turbine as being bigger. Vane design is everything in a turbocharger. The radius is one factor, but you need to take into considerations the width of each vane, how many vanes, the total surface area of the vane and curvature of the vane. This is the most important consideration when trying to factor maximum torque and speed to the compressor side.

[Wazari]

Wazari
<snip>
What are the pros and cons of small and large compressor in using shaft power?
Would MGU-H been always on generator mode of a VGT was allowed?

Generally speaking, a larger compressor (total surface area of the compressor vanes, not necessarily radius size) will deliver more pressure at a lower RPM. However the larger compressor will require more torque to drive it. So again, as I mentioned previously, it becomes a balancing act. Mercedes obviously has done the best job in balancing all these factors taking into account fuel flow which will dictate boost levels to the ICE, how much torque and the cut off point to send to the MGU-H unit, how much assist to send from the MGU-H unit to the turbine, etc.

I think the answer to your last question would be no. A VGT or VNT would probably allow longer periods for the MGU-H to be in generator mode, but I would think you would still want the MGU-H to keep your turbocharger spooled during certain periods on each lap. Even with a VGT, I am pretty sure that at lower RPM's you would want the MGU-H to be in motor mode. I am really no more of an expert that most of you when it comes to the MGU-H unit. I have seen one up close but have never worked with one or familiar with its inner workings or design.