Offset cylinder explained.

[gruntguru]

How can an exhaust turbine still be developing significant power in electric supercharging mode with waste-gate open and exhaust gasses by-passing the turbine?.

. . . . Opening the waste-gate comes at the expense of a lower MGU-H recuperation: in fact, the average MGU-H recuperation (on straight) is roughly zero if the waste-gate is kept always open. . . .

If the turbine is not developing significant power, the "average MGU-H recuperation" would be negative. There are only two alternatives
1. The turbine still develops significant power with the wastegate open. or:
2. The quoted research paper is wrong.

[vorticism]

"Roughly zero recuperation" would not rule out motoring/expenditure i.e. negative recuperation. I would add that as a third option to your list. (3. The paper is correct; the turbine produces near zero power and requires MGU motoring of the compressor during WGO.)

[saviour stivala]

It is not like this here latest research paper quoted is the first one, there were others before it, so if this paper is wrong all others before it were wrong. But the most incredible is not doubting a published research paper, but what makes one persists in pushing-out his opinion that the MGU-H can in fact recuperate when the waste-gate is open so exhaust is bypassing the turbine. The simplest question that can be asked is, If when the waste-gate is opened with exhaust bypassing the turbine, the turbine power diminishes, how can it power either the MGU-H or the compressor, let alone both of them together? And, if the MGU-H is not recuperating at end of straight engine speed because of waste-gate being open and exhaust bypassing the turbine, with the result of the turbine not having the power to power MGU-H, and so neither the compressor, What does one expects the MGU-H will be doing other then motoring the compressor.

[gruntguru]

In which case the paper is badly worded which I doubt. The text elsewhere indicates they know the difference between zero and negative. You also have this:

By contrast, for the considered high-performance power unit the waste-gate is used to increase the engine power by diminishing the exhaust manifold pressure. The turbine power extraction is reduced and therefore the MGU-H power recuperation goes roughly to zero . . .

[Holm86]

Why do people have such a hard time staying on topic on this forum???

[saviour stivala]

In which case the paper is badly worded which I doubt. The text elsewhere indicates they know the difference between zero and negative. You also have this:

By contrast, for the considered high-performance power unit the waste-gate is used to increase the engine power by diminishing the exhaust manifold pressure. The turbine power extraction is reduced and therefore the MGU-H power recuperation goes roughly to zero . . .

Technically speaking the formula one turbocharger did not need a waste-gate, The pop-off/blow-off valve was enough as a control safety system, In addition the system has a mandated MGU-H which totally controls the turbocharger, They also use compressor intake throttling. As such the additional use of a waste-gate was solely intended to extract the maximum possible output from the power unit by relieving the ICE of any back pressure when waste-gate is opened.

[saviour stivala]

The 2021 quoted research paper ''is wrong or badly warded''. This research paper is by:- (1) Institute for dynamic systems ETH Zurich. (2) Department of mechanical engineering Politecnico Di Milano. (3) Power unit performance and control strategies FERRARI.
What is the possibility of the 2014 research paper by the department of engineering science at university of Oxford (optimal control theory and FERRARI'S turbo-electric hybrid) being also wrong or badly warded?. it quoted:-''Opening the waste-gate boosts ICE power because the back pressure in the exhaust system is reduced. - in its qualifying condition the engine is run with waste-gate open for sustained period of time when maximum power is needed. during these periods of time the energy store will be supplying both the MGU-K and MGU-H with the later used to drive the engine boost compressor".

[Brian.G]

Thats cylinder offset anyways...

Brian,

[gruntguru]

. . during these periods of time the energy store will be supplying both the MGU-K and MGU-H with the later used to drive the engine boost compressor".

Yes but no one is saying how much MGU-H power is required in this mode or whether any power is available from the turbine. Certainly the wastegate opening could be modulated to achieve the best compromise between exhaust back pressure and MGU-H power consumed. Reducing the ES drain during this mode would be highly advantageous by allowing the mode to be used for longer periods each lap.

[gruntguru]

Thats cylinder offset anyways...
Brian,

Topic offset.

[Brian.G]

Thats cylinder offset anyways...
Brian,

Topic offset.

Very good...

I'm thinking, if I was to redesign my straight 6 N52 engine with enough offset - I may not have to pay for the fuel?

Brian,

[vorticism]

Correct, with enough offset frictional losses, pumping losses, and fuel consumption are totally eliminated.

. . during these periods of time the energy store will be supplying both the MGU-K and MGU-H with the later used to drive the engine boost compressor".

Yes but no one is saying how much MGU-H power is required in this mode or whether any power is available from the turbine. Certainly the wastegate opening could be modulated to achieve the best compromise between exhaust back pressure and power required to drive the MGU-H. Reducing the ES drain during this mode would be highly advantageous by allowing the mode to be used for longer periods each lap.

I suspect that one of the reasons for the WG pipe rules being added was to limit development of this mode. Even so, it was the Ferrari engines which made the most noise during WGO even after the small diameter pipe rules were eliminated.

[Stu]

If there is nothing more on cylinder offset should I lock the thread?

There will be a clean-up (I would propose that the the MGU-H content be moved, rather than deleted).

[saviour stivala]

If there is nothing more on cylinder offset should I lock the thread?

There will be a clean-up (I would propose that the the MGU-H content be moved, rather than deleted).

Excuse me, but if I am permitted, at least from my side the subject matter truth lays on more than one technical research paper. this because as you said, personal opinion is just that after all.

[Zynerji]

I have one more question.

In a V8 configuration, one could deck the main-bearing cap interface on the block, say .020", reinstall the cap and align-hone the journals to raise the crank height in the block? In a 90 degree configuration, this would offset .010" as well as raise the piston at TDC by .010", thus needing shorter rods?

Thanks!