Mercedes Power Unit Hardware & Software

[Muulka]

Then you create a better flowing turbine to manage that temperature difference. There's enough energy in the exhaust to run the MGU-H -> MGU-K at half power(60kW) and charge the batteries at the same time, it's believed Mercedes can do 80kW + battery charging.

And this actually makes a lot of sense. We all sing praises of Mercedes chassis, but there's something most people overlook. Relying less on the MGU-K to harness electricity has a big influence on chassis performance, particularly under braking.

I think a big part of their advantage is their chassis is designed around using less MGU-K and more MGU-H to harvest electricity.

*Merry Christmas everyone.

Surely the MGUK is the best energy to recover? By recovering under braking you lose nothing, but need less cooling on your rear brakes (improving aero). If you're relying more on the H recovery you'll be limiting your engine power more as well; backpressure is the enemy of power.

There's a lot of assertions in this forum without any real evidence behind them...

[godlameroso]

The MGU-K can only harvest 2MJ of energy, the fact that Mercedes has not bothered to revise their MGU-K all season gives evidence to my point of view. If you can harvest 3MJ per lap from the MGU-H, then you can get away with only 1MJ from the K, seeing as you can only use 4MJ per lap anyway. Nowhere did I say that you no longer use the MGU-K I said that you rely on it for harvesting less than your competition.

Do you suppose they use a lot of MGU-K recovery during qualifying? Wouldn't they if it increased performance?

[FPV GTHO]

I think that could work in qualifying, but in the race I don't feel they would have the liberty of picking and choosing where to harvest.

[wuzak]

The MGU-K can only harvest 2MJ of energy, the fact that Mercedes has not bothered to revise their MGU-K all season gives evidence to my point of view. If you can harvest 3MJ per lap from the MGU-H, then you can get away with only 1MJ from the K, seeing as you can only use 4MJ per lap anyway. Nowhere did I say that you no longer use the MGU-K I said that you rely on it for harvesting less than your competition.

Do you suppose they use a lot of MGU-K recovery during qualifying? Wouldn't they if it increased performance?

But if you can harvest 2MJ from the MGUK and 3MJ from the MGUH you can then have 5MJ for deployment rather than 4MJ.

[wuzak]

Do you suppose they use a lot of MGU-K recovery during qualifying? Wouldn't they if it increased performance?

I don't think they use much, if any, MGUK recovery in qualifying. That goes for all teams.

[Moose]

The MGU-K can only harvest 2MJ of energy, the fact that Mercedes has not bothered to revise their MGU-K all season gives evidence to my point of view. If you can harvest 3MJ per lap from the MGU-H, then you can get away with only 1MJ from the K, seeing as you can only use 4MJ per lap anyway. Nowhere did I say that you no longer use the MGU-K I said that you rely on it for harvesting less than your competition.

Do you suppose they use a lot of MGU-K recovery during qualifying? Wouldn't they if it increased performance?

But if you can harvest 2MJ from the MGUK and 3MJ from the MGUH you can then have 5MJ for deployment rather than 4MJ.

Right - which lets you make the MGU-K smaller. The MGU-K is the less favourable way to generate power, since it relies on specific track characteristics to have power generated at any one spot. Meanwhile, the MGU-H works anywhere where the engine is running (i.e. anywhere).

[godlameroso]

The MGU-K induces oversteer on corner entry, it's also not a light switch, but rather harvesting power is variable. To counter this oversteer tendency the engine accelerates a tiny bit which wastes a small amount of fuel. There is a careful balancing act in order to get good harvesting without being difficult to control, and without consuming too much extra fuel.

Of course a powerful and efficient ICE helps in this matter tremendously, because it's efficient so the engine can compensate for the oversteer of braking with the rear wheels without incurring too much of a penalty. Likewise, because of the powerful and efficient engine it can generate more electrical energy via the MGU-H and use a lower percentage of MGU-K harvesting and by consequence have better stability under braking.

The limits of tuning, and optimizing these power units still has another season or two, perhaps with the lack of token restrictions their advancement will be slightly accelerated.

[FPV GTHO]

The MGU-K can only harvest 2MJ of energy, the fact that Mercedes has not bothered to revise their MGU-K all season gives evidence to my point of view. If you can harvest 3MJ per lap from the MGU-H, then you can get away with only 1MJ from the K, seeing as you can only use 4MJ per lap anyway. Nowhere did I say that you no longer use the MGU-K I said that you rely on it for harvesting less than your competition.

Do you suppose they use a lot of MGU-K recovery during qualifying? Wouldn't they if it increased performance?

But if you can harvest 2MJ from the MGUK and 3MJ from the MGUH you can then have 5MJ for deployment rather than 4MJ.

Right - which lets you make the MGU-K smaller. The MGU-K is the less favourable way to generate power, since it relies on specific track characteristics to have power generated at any one spot. Meanwhile, the MGU-H works anywhere where the engine is running (i.e. anywhere).

The MGUK is deploying 4MJ+ regardless of the harvesting strategy, I wouldn't think that would have a big impact on the unit size.

[ME4ME]

The MGU-K can only harvest 2MJ of energy, the fact that Mercedes has not bothered to revise their MGU-K all season gives evidence to my point of view.

It doesn't really.. Did they revise the MGU-H or the battery pack? Some components are already at a highly developed stage. There is no need to induce unreliability or uncertainty for the sake of tiny weight-savings or whatever, on the MGU-K.

seeing as you can only use 4MJ per lap anyway.

You should know better.

[godlameroso]

Right 4MJ from the ES and whatever you can get bypassing the ES, via MGU-H to MGU-K.

That doesn't change the fact harvesting from the MGU-K affects chassis performance.

[Muulka]

Right 4MJ from the ES and whatever you can get bypassing the ES, via MGU-H to MGU-K.

That doesn't change the fact harvesting from the MGU-K affects chassis performance.

It won't really, though, will it? That's why they have the BBW systems; they make sure that the targeted brake bias is met regardless of MGUK recovery.

[Muulka]

The MGU-K can only harvest 2MJ of energy, the fact that Mercedes has not bothered to revise their MGU-K all season gives evidence to my point of view. If you can harvest 3MJ per lap from the MGU-H, then you can get away with only 1MJ from the K, seeing as you can only use 4MJ per lap anyway. Nowhere did I say that you no longer use the MGU-K I said that you rely on it for harvesting less than your competition.

Do you suppose they use a lot of MGU-K recovery during qualifying? Wouldn't they if it increased performance?

You misunderstand - you'll want to rely more on the MGUK for recovery, as the BBW systems mean that it has no impact on performance, but then you have more energy to deploy. On the other hand, recovering from the exhaust limits ICE power output, which will slow you down

[Muulka]

The MGU-K can only harvest 2MJ of energy, the fact that Mercedes has not bothered to revise their MGU-K all season gives evidence to my point of view. If you can harvest 3MJ per lap from the MGU-H, then you can get away with only 1MJ from the K, seeing as you can only use 4MJ per lap anyway. Nowhere did I say that you no longer use the MGU-K I said that you rely on it for harvesting less than your competition.

Do you suppose they use a lot of MGU-K recovery during qualifying? Wouldn't they if it increased performance?

You misunderstand - you'll want to rely more on the MGUK for recovery, as the BBW systems mean that it has no impact on performance, but then you have more energy to deploy. On the other hand, recovering from the exhaust limits ICE power output, which will slow you down

[wuzak]

Right 4MJ from the ES and whatever you can get bypassing the ES, via MGU-H to MGU-K.

That doesn't change the fact harvesting from the MGU-K affects chassis performance.

Maybe so, but more available energy affects lap performance more.

[wuzak]

You misunderstand - you'll want to rely more on the MGUK for recovery, as the BBW systems mean that it has no impact on performance, but then you have more energy to deploy. On the other hand, recovering from the exhaust limits ICE power output, which will slow you down

There is a point at which recovering more energy from the exhaust will reduce performance.

But, generally speaking, the overall system is more efficient when recovering energy below that point, so while you lose outright power you have more power available for a longer period and less (or no) fuel saving required.