Re: Honda Power Unit
Posted: 04 Aug 2017, 08:00
Does it? If one ICE produces peak 600 kWh @ 1.25 km/L and another 595 kWh @ 1.5 km/L, which would you consider the more efficient ICE ?
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Re: Honda Power Unit
Posted: 04 Aug 2017, 08:12
Re: Honda Power Unit
Posted: 04 Aug 2017, 08:37
I'm sure this was spoken about with last years PU. There was talk Honda actually had what we would call a competitive "peak power" figure however, it had comparatively peaky delivery.
When it comes down to it, we really have nothing solid to go on with these PU's as a whole, so who really knows. Speculation is fun though.
Information I would call solid, in regards to Honda's PU performance and the areas in which they are lacking, is Hasegawa's frank yet honest admissions that they ar enot satisfied and that it is the ICE itself that needs the most attention to draw out more power. Specifically, the much talked about combustion chamber design and injection system.
Re: Honda Power Unit
Posted: 04 Aug 2017, 08:53
The extra weight could explain the bigger lap differences at the beginning of the race, which become smaller at the end of the race, but I cannot see why if Honda have almost equal power with the other engines they cannot deliver better qualification laps when the weight in all cars is at minimum and almost equal?GhostF1 wrote: ↑04 Aug 2017, 08:37I'm sure this was spoken about with last years PU. There was talk Honda actually had what we would call a competitive "peak power" figure however, it had comparatively peaky delivery.
When it comes down to it, we really have nothing solid to go on with these PU's as a whole, so who really knows. Speculation is fun though.
Information I would call solid, in regards to Honda's PU performance and the areas in which they are lacking, is Hasegawa's frank yet honest admissions that they ar enot satisfied and that it is the ICE itself that needs the most attention to draw out more power. Specifically, the much talked about combustion chamber design and injection system.
Hm, OK - I forgot that with equal fuel the other engines could extract more power, so called qualification mode.
Re: Honda Power Unit
Posted: 04 Aug 2017, 09:36
I think, one is referring to the combustion process and the other to the pu as a whole
Re: Honda Power Unit
Posted: 04 Aug 2017, 09:40
I think you are being too subtle.
Obviously in conventional vehicle terms the second is more efficient. So efficiency in these terms is how the power is used to move the vehicle
For F1 efficiency is measured by lap time against fuel mass. (I haven't found a good metric for this, but it doesn't matter)
What wuzak is referring to is the power units ability to convert fuel to usable power.
Of course efficiency in lap time depends on how that power is mixed between ICE and MGU-H. And the further deployment of those two to achieve the best possible lap time. Equivalent to your km/L measure.
Most people on this forum don't make those distinctions. They are interested in "peak" power and fuel usage, "efficiency". They don't really make the link Wuzak does, let alone the complexities of deployment.
You are not helping people with their understanding when you, an expert, talk about "peak power" ( an earlier post), or offer confusing examples involving measures of efficiency that have no relevance to this F1 formula.
Re: Honda Power Unit
Posted: 04 Aug 2017, 10:44
Are not all engines 145 kg?
Re: Honda Power Unit
Posted: 04 Aug 2017, 11:13
I dunno.
The message is "it's not just about how high the line on the graph goes, the area under it is also important".
That's been the case ever since fuel rate limits and fuel capacity constraints were in the rules (and for the latter, a long time before that, since fuel=weight and weight hurts everything else).
Fuel economy leads to a lighter overall car weight (especially at the start of a race). This has a beneficial effect on power to weight ratio, on tyres, brakes, on various things like that.
It's a longwinded way of saying that a more economical PU - with less overall power - can still be faster in certain circumstances. For balance I should preemptively agree with anyone who points out that the cars spend most of their time in such a high drag aero state that straight "power to weight" is a secondary consideration.
Re: Honda Power Unit
Posted: 04 Aug 2017, 11:15
That's the minimum weight in the rules. It's entirely feasible that one or other of the PUs is over that number, especially if the manufacturer involved has been trying to make it into a very reliable unit (by using either more material or denser materials).
Re: Honda Power Unit
Posted: 04 Aug 2017, 11:22
IMO you made 2 mistakes here.godlameroso wrote: ↑04 Aug 2017, 00:14Maybe, maybe not.Tommy Cookers wrote: ↑03 Aug 2017, 22:10the crankshaft torque does not propel the car - the torque around the axle does
http://i.imgur.com/H4g7Qxw.jpg
Naturally aspirated engine with 4.11 final drive measured at the wheels.
http://www.svtperformance.com/wp-conten ... o-Test.jpg
Turbocharged engine with 3.67 final drive measured at the wheels.
Why does engine 2 produce nearly 100 ft lbs more torque than engine 1 when measured at the wheels, despite similar peak power?
First, your grafs show peak crank torque, but messured at wheels and calculated into crank torque.
Second, peak wheel tourqe doesn't happen at same rpm as peak crank torque, but at peak power.
(Maybe I misunderstood you here. It's not my intention to be a smarta*s)
Re: Honda Power Unit
Posted: 04 Aug 2017, 11:34
I think if second one produce more exhaust gass more powerful spin at mgu-h causing more electric prodoction, it could be good but power income can be zero because of heavier fuel loads. I don't know
Re: Honda Power Unit
Posted: 04 Aug 2017, 11:34
Oooops, tried to edit and can't remove.
Sorry for double post
Sorry for double post
Re: Honda Power Unit
Posted: 04 Aug 2017, 11:36
Re: Honda Power Unit
Posted: 04 Aug 2017, 11:38
The questions is at what cost this conversion is done. Less efficient engine could produce the same usable power but it needs more fuel. I don't see any difference between road cars and F1 in this. The lap time depends on usable power, on time per lap that this usable power is available, and the work that should be done (how much weight it should be moved around). Obviously, if you have the same power but less time at this power and more weight you will get worst lap time. Probably the crucial moment is the time at full power. If you have more weight you must spend more energy from ERS, and if you cannot compensate this with MGU-H you are ending with less time at full power and not very good lap time.
Re: Honda Power Unit
Posted: 04 Aug 2017, 11:43
Actually, no. I made a mistake there.
In gear acceleration is highest at peak torque rpm.
But, peak wheel tourqe at certain wheel rpm(certain vehicle speed) happens at peak power.