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Cold Fussion wrote:

Blaze1 wrote: xpensive posted of 600Hp from the ICE, with 160Hp from the ES/MGU-H leading to a total of 760Hp and a total efficiency of 44%.

This doesn't make any sense, unless the mgu-h output was 160 hp.

And where do you thing the power in the battery originally came from if not the fuel?

xpensive wrote:

Cold Fussion wrote:

Blaze1 wrote: xpensive posted of 600Hp from the ICE, with 160Hp from the ES/MGU-H leading to a total of 760Hp and a total efficiency of 44%.

This doesn't make any sense, unless the mgu-h output was 160 hp.

And where do you thing the power in the battery originally came from if not the fuel?

You have the braking regeneration as well.

Remove that ERS , its blocking overtaking omfg...

Kers Come back T_T

Actually, I think the "the new engine formula is blocking overtaking" thing is a bit overblown. Yes, you no longer have push to pass with KERS, but you do have DRS working better. You used to get DRS trains, where if the second driver couldn't overtake, then no one could, because they'd all hit the rev limiter no matter how big a drag reduction they got.

Now, that's not true, simply because they are all so far from the rev limiter all the time.

Cold Fussion wrote:

xpensive wrote:

Cold Fussion wrote: This doesn't make any sense, unless the mgu-h output was 160 hp.

And where do you thing the power in the battery originally came from if not the fuel?

You have the braking regeneration as well.

You do realise that energy also came from the fuel don't you?

wuzak wrote:

Pierce89 wrote:Do you guys not realize that any energy in the ES also came from the fuel?

The problem is, for efficiency calculations, you do not know how much fuel was burned to generate the stored electricity.

And the energy is not from the 100kg/hr fuel that is being run through the engine at the point in time at which the efficiency is measured/calculated.

Yes, we realize that. To get a legitimate TE figure on the PUs the power(with electrical powere)should be added up and averaged into kw/h. Then we could work on a legitimate overall TE.

No! That would include energy that has been used more than once. You cannot include regenerative braking in an efficiency calculation.

The total work (mechanical energy) produced from the fuel is crankshaft work from the ICE plus work put into the MGUH. (90+% of the MGUH work is converted into electricity). If you totalled all this work over the course of a race and divided by the total energy in the fuel consumed, you would have the average efficiency of the PU.

Mercedes claim of 40+% is the efficiency of the compounded ICE system.

gruntguru wrote:No! That would include energy that has been used more than once. You cannot include regenerative braking in an efficiency calculation.
...

"Energy that has been used more than once"? An interesting concept that, as energy is indestructible, kindly elaborate?

Pierce89 wrote:

Cold Fussion wrote:

xpensive wrote: And where do you thing the power in the battery originally came from if not the fuel?

You have the braking regeneration as well.

You do realise that energy also came from the fuel don't you?

The problem is that the fuel that is used to store energy in the ES is not part of the 100kg/s on which you are basing your efficiency calculation.

It is also, partly, chassis dependent. ie some cars are faster in a straight line, allowing more braking potential, some are better, more stable, under braking and can recover energy better.

xpensive wrote:

gruntguru wrote:No! That would include energy that has been used more than once. You cannot include regenerative braking in an efficiency calculation.
...

"Energy that has been used more than once"? An interesting concept that, as energy is indestructible, kindly elaborate?

Well, it has been recovered....

wuzak wrote: ....
Well, it has been recovered....

Like the energy is coming out of the MGU-H perhaps?

wuzak wrote:

Pierce89 wrote:

Cold Fussion wrote: ...
The problem is that the fuel that is used to store energy in the ES is not part of the 100kg/s on which you are basing your efficiency calculation.
...

I beg to differ, if the braking energy is not originating from the 100 kg/h, where in the world would it come from, the sun?

xpensive wrote:

wuzak wrote: ....
Well, it has been recovered....

Like the energy is coming out of the MGU-H perhaps?

Recovered and stored for use at a different time. Which can also be said for the MGUH.

Here is a simple calculation for you.

Assume fuel energy density is 45MJ/kg, and the MGUH generates 60kW to send to the MGUK. That means that to use the full 120kW an additional 60kW has to come from the ES.

This energy has been recovered and stored from braking/MGUH over the previous lap/laps. But how much fuel flow does it represent?

If we assume no losses in conversion anywhere, the 60kW equates to 4.8kg/hr of fuel flow - ie nearly 5% of the maximum allowed fuel flow.

Since the efficiency is the output power of the PU divided by the potential power of the fuel, should not the potential power of the fuel which was used to generate and store the energy to the ES be used in the calculation for efficiency?

xpensive wrote: I beg to differ, if the braking energy is not originating from the 100 kg/h, where in the world would it come from, the sun?

It is coming from the 100kg/hr fuel flow used somewhere else in the lap/race. Not from the point at which the 100kg/hr is being measured and efficiency calculated.

Nobody said it's as clear cut as MGU-H power going to the MGU-K, but one way or the other it is originating from the 100 kg/h fuel flow, there's no other way. Now, how to calculate the losses and time-lag from the previous lap is nothing I'd like to try.

But I'm certain that MHPE has developed a model for it.