saviour stivala wrote: ↑
Wed Jul 03, 2019 8:05 pm
stevesingo wrote: ↑
Wed Jul 03, 2019 2:57 pm
saviour stivala wrote: ↑
Wed Jul 03, 2019 12:06 pm
Suggesting that a particular formula car/one engine peak power was being produced at 11500 rpm means that car/engine maximum fuel flow has been shifted from the mandatory 10500 rpm to 11500 rpm.
Conventionally you would expect peak power to coincide with the lowest rpm where max fuel flow is available.
These engines are not conventional. Add in the effects of MGU-K and MGU-H in particular and I don't suppose it is clean cut.
The rules mandate a maximum fuel flow of 100kg/h @ 10500rpm, and it is at this maximum fuel flow and maximum RPM were each of the 31500 combustions per minute produced will peak their outputs. Each of these combustions will peak their outputs by using the 0.0528 grams of fuel permitted by the rules. Past that maximum RPM the number of combustions per minute increases, any additional increase in the number of combustions per minute will have to share the same 0.0528 grams of fuel permitted with the other 31500 combustions, this means less grams of fuel per combustion, less grams of fuel per combustion means each combustion is being weakened from the peak they had reached at the maximum permitted fuel flow.
The above is correct although you continuously specify 10,500 rpm as the point of maximum fuel flow which is not correct. Maximum fuel flow is available from 10,500 to 15,000 rpm.
The quote below is not correct.
Each combustion of the best of these engines at its peak at the permitted maximum fuel flow/RPM, are bettering 0.0266 BHP per combustion, which means each cylinder is bettering 140 BHP at their highest possible racing mode.
1. It is not correct to equate fuel-per-combustion event (fuel/CE) to power/CE. It should be energy/(CE).
2. Although the fuel/(CE) and energy/(CE) will reduce as rpm increases above 10,500, the power available is constant because there are more CE per unit time. (Power = energy per unit time).
3. (As I said previously) the only reason power reduces above 10,500 is increasing friction and other losses and this will be a gradual tapering of power.
4. It is relatively easy to shift the peak power rpm slightly (to say 11,000) by optimising various engine parameters for the higher rpm. Because of friction etc the peak power will be slightly less than it would be if optimised for 10,500. However the average power across the rpm range used will be higher if optimised for the higher rpm. I have created two power curves to illustrate the difference. Look at the operating range from 10,500 to 11,500 and decide which power curve you would prefer.