Dunno, downshifting can be decisive factor. They probably want to get to as close to 15k as possible, making engine a big pump for ERS-H. Wonder what about throttle regs.xpensive wrote:I still believe the key here is the wide power-band, you don't necessarily need to have the gearing that precise?
I think this is likely. They would probably make a ratio change after Monaco ahead of Canada.Paul wrote:Also there is that allowed change of ratios once, so teams can divide the season in two parts and start it with, say, a "Monaco selection" and end it with a "Monza" one.
Why would the ICE produce more xhausts at 15k than 10.5, when the amount of fuel burnt is the same?timbo wrote:Dunno, downshifting can be decisive factor. They probably want to get to as close to 15k as possible, making engine a big pump for ERS-H. Wonder what about throttle regs.xpensive wrote:I still believe the key here is the wide power-band, you don't necessarily need to have the gearing that precise?
I meant during breaking when it would work as pump.xpensive wrote:Why would the ICE produce more xhausts at 15k than 10.5, when the amount of fuel burnt is the same?
The change is allowed only for 2014. And only because with the new car and engine regs teams may have made some cockups.Paul wrote:Also there is that allowed change of ratios once, so teams can divide the season in two parts and start it with, say, a "Monaco selection" and end it with a "Monza" one.
The xhausts would be relatively constant from 10,500-15,000rpms. The compressor work required will fall, however. The ratio between the change of xhausts and compressors could mean that the rise in MGUH power generated outstrips the increase in friction. That is, combined power would be greater at 15,000 than 10,000rpm (and not using power from the ES).xpensive wrote:Why would the ICE produce more xhausts at 15k than 10.5, when the amount of fuel burnt is the same?
Ideally, you would want to shift 10.5 - 13k to minimize friction, but it's no disaster if you go up to 15k.
Will it really, when fluid power is volumetric flow times pressure, should this not stay the same coming out of the compressor?wuzak wrote: ...
The xhausts would be relatively constant from 10,500-15,000rpms. The compressor work required will fall, however. The ratio between the change of xhausts and compressors could mean that the rise in MGUH power generated outstrips the increase in friction. That is, combined power would be greater at 15,000 than 10,000rpm (and not using power from the ES).
Aero philosophy depends more by tracks' design than by rules.timbo wrote:Already raised the same question. It also may change the aero philosophy as well.tok-tokkie wrote:Will not the fixed 8 gear ratios + increased recovered energy storage + 10500rpm - 15000rpm flat power curve not make overtaking much more likely next season? The following driver will not have the rev limiter ceiling except at Monza. Both the pursuer & the pursued will have the same options but the initiative lies with the pursuer. Can play out over many laps.
Tommy Cookers wrote:one last try here !
broadly speaking at 10500 rpm the engine has a designed boost and a (maximal) CR matched to this boost
the efficiency (of our lightly-compounded engine) is dominated by the CR
at 15000 rpm the cylinder contents will be 43% less so this CR is now much too low and will now cost engine efficiency ie power
(a lot more power than is available within the friction/rpm vs. supercharging work/rpm tradeoff)
at 15000 the engine is halfway to being N/A but the CR is not matched to this
whatever is done to somewhat alleviate this fundamental problem (I have made my suggestions)
the problem will surely be minimised (by minimising the speed range eg 10500-12300 is all we need)
This could be a stupid idea. But I want to hear peoples thoughts on this.Tommy Cookers wrote:one last try here !
broadly speaking at 10500 rpm the engine has a designed boost and a (maximal) CR matched to this boost
the efficiency (of our lightly-compounded engine) is dominated by the CR
at 15000 rpm the cylinder contents will be 43% less so this CR is now much too low and will now cost engine efficiency ie power
(a lot more power than is available within the friction/rpm vs. supercharging work/rpm tradeoff)
at 15000 the engine is halfway to being N/A but the CR is not matched to this
whatever is done to somewhat alleviate this fundamental problem (I have made my suggestions)
the problem will surely be minimised (by minimising the speed range eg 10500-12300 is all we need)
air density is proportional to absolute temperature, is the air before the intercooler hot enough?Holm86 wrote:This could be a stupid idea. But I want to hear peoples thoughts on this.Tommy Cookers wrote:one last try here !
broadly speaking at 10500 rpm the engine has a designed boost and a (maximal) CR matched to this boost
the efficiency (of our lightly-compounded engine) is dominated by the CR
at 15000 rpm the cylinder contents will be 43% less so this CR is now much too low and will now cost engine efficiency ie power
(a lot more power than is available within the friction/rpm vs. supercharging work/rpm tradeoff)
at 15000 the engine is halfway to being N/A but the CR is not matched to this
whatever is done to somewhat alleviate this fundamental problem (I have made my suggestions)
the problem will surely be minimised (by minimising the speed range eg 10500-12300 is all we need)
The way the regulations work now you have max performance at 10500 rpm. And as TC says this rpm spot is likely where the CR is designed top be optimal. Revving the engine beyond 10500 rpm would need the boost to decrease to maintain A/F ratio. This means that from 10500 rpm to 15000 the powercurve should dip slightly because of increased inner friction and moving away from the CR sweet spot.
And here is the idea that might sound silly. But what if you bypassed the intercooler after 10500 rpm?? This would mean that the density of the air decreases which means that you can run more or the same boost maintaining the amount of air that you compress in the cylinder. This means that the total CR is maintained as the volume stays the same as at 10500 rpm. But the air holds less oxygen which makes it possible to keep the A/F ratio without decreasing the boost.
Hope you guys understand what I mean
Problem with de-activating cylinders is that they keep the friction without adding power.chip engineer wrote:Tommy Cookers wrote:one last try here !
broadly speaking at 10500 rpm the engine has a designed boost and a (maximal) CR matched to this boost
the efficiency (of our lightly-compounded engine) is dominated by the CR
at 15000 rpm the cylinder contents will be 43% less so this CR is now much too low and will now cost engine efficiency ie power
(a lot more power than is available within the friction/rpm vs. supercharging work/rpm tradeoff)
at 15000 the engine is halfway to being N/A but the CR is not matched to this
whatever is done to somewhat alleviate this fundamental problem (I have made my suggestions)
the problem will surely be minimised (by minimising the speed range eg 10500-12300 is all we need)
That makes sense to me. Many pages back, someone suggested de-activiating some of the cylinders at high rpm. If withholding both fuel and air from some cylinders is allowed, it could extend the rpm range where the CR is optimum.
Under those conditions, the unused cylinders would also not be absorbing any combustion heat, further increasing efficiency.