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KERS won't influence fuel-consumption - it's not a roadcar...

Metar wrote:KERS won't influence fuel-consumption - it's not a roadcar...

I disagree...

First, we understand that accelerating is the most fuel-intensive part of driving. I don't think anything else is possible.

If KERS is used as boost coming out of turns, it's helping the car to accelerate. Because there is an ultimate maximum RPM the engine can run at, KERS is only helping it get to max rpm sooner.

Helping it get there sooner means it's doing some of the work of the engine, meaning the engine isn't having to do as much work, or work for as long, however you wish to look at it.

That's my .02 at least.

The FOZ wrote:

Metar wrote:KERS won't influence fuel-consumption - it's not a roadcar...

I disagree...

First, we understand that accelerating is the most fuel-intensive part of driving. I don't think anything else is possible.

If KERS is used as boost coming out of turns, it's helping the car to accelerate. Because there is an ultimate maximum RPM the engine can run at, KERS is only helping it get to max rpm sooner.

Helping it get there sooner means it's doing some of the work of the engine, meaning the engine isn't having to do as much work, or work for as long, however you wish to look at it.

That's my .02 at least.

I would agree if the KERS system was giving the same rate of acceleration as the engine alone (i.e. the KERS is taking some of the load) but since it's causing it to accelerate faster than without it requires the same amount of power from the engine otherwise it wouldn't accelerate faster.

And since KERS can only engage at over 100km/h and when full throttle is depressed it cannot be used to save fuel.

The FOZ wrote:Helping it get there sooner means it's doing some of the work of the engine, meaning the engine isn't having to do as much work, or work for as long, however you wish to look at it.

Perhaps, although KERS only kicks in after 100kph, and it also means the engine is running at max rpm for longer, hence using more fuel.

I think the overall effect is neglible because it is used for a small momentary boost, but you would get fuel savings if it had unlimited use.

Metar wrote:KERS won't influence fuel-consumption - it's not a roadcar...

you can set the KERS to save fuel
I think it will useful next year.

Scania wrote:

Metar wrote:KERS won't influence fuel-consumption - it's not a roadcar...

you can set the KERS to save fuel
I think it will useful next year.

Fuel energy content is in the range of 45-50 MJ/kg. With 2.5 kgs of fuel per lap it is 112.5-125 MJ. KERS capacity is 0.4 MJ per lap. Won't matter much.

KERS can save fuel.

80 more HP from KERS

You just set the ECU to make 80 less HP from the engine at the same time.

The car will not be faster but Same horsepower less fuel used.

for 6.67 secs.. for the rest you are getting smoked by the other cars

timbo wrote:Fuel energy content is in the range of 45-50 MJ/kg. With 2.5 kgs of fuel per lap it is 112.5-125 MJ.

Is this with or without engine efficiency (25%-30%) factored in?

I believe 45 MJ/kg is a good approximation of the thermal-energy you get if you simply burn the gasoline.

Fuel consumption in 2010 is going to be more than in 2009 because the cars are heavier at the beginning.

But yeah KER saves gas but come to think of it the factional amount of gas saved will be offset by the lack off precision in the pit stop refueling process in 2009. Eg.. you save 1kg of fuel for one stint so you have an extra 1/2 lap.. but all of that advantage is gone because you can't pitstop halfway through the lap and the fueling rig is not precise enough to inject precisely 1kg less fuel that you are not going to use anyways. So yeah it saves fuel but that advantage is not really useful in 2009.


In 2010, I don't know.. the fuel consumption is much worse because of the heavier cars, then it gets better as the race continues. And no refueling so if KERS could give an extra lap or two you would notice it. But then AGAIN.. I don't think any team is bold enough to make the fuel the car just enough to make it across the line and a race is so unpredictable! That one or two laps less fuel in the car can be risky!! And it will only give the advantage at the start of the race if you assume that all the cars weigh more or less the same after crossing the line.

in 2010, the team have 800kj of KERS power per lap. For those of F1 track, it is around 1 min for full thottle.

for Pt=E, we have 800kj in 60sec.

the k of power & energy are cancel out, that means
"Power X 60sec=800kj"
"Power=800/60"
"Power=13.33kW"
"13.33/0.7=19.05hp"

that means new KERS can apply 20hp/each hole lap.

if you don't use Power booste, you can tune down the engine power 20hp but won't lose any wheel power(exclude Booste power).

joseff wrote:

timbo wrote:Fuel energy content is in the range of 45-50 MJ/kg. With 2.5 kgs of fuel per lap it is 112.5-125 MJ.

Is this with or without engine efficiency (25%-30%) factored in?

Yep, I screwed up.
But even with 25-30% efficiency estimate you'd get not less than effective 28 MJ per lap. So 0.4 MJ is less than 1.5 percent. With 50 lap race it is about 1.9 kg of saved fuel.

And all that is just assuming that carrying those 1.9kg less fuel, or letting the engine burn 1.9kg more, ends up faster over the distance than using that small KERS boost in addition.