No worries, The answer depends on how tight the radius of the oval/circular track is:-CAEdevice wrote:Another question: it's clear that inertial forces have the most important influence on fuel consumption, but what would happen in a track with little longitudinal inertial forces like Indianapolis?
1, If the radius is very large (or the banking is very steep) then the speed of the "normal" car will be limited by the power of the engine. In this case, dropping the car's drag by 10% can either result in the car going faster (gearing permitting), or if the driver lifts the throttle slightly; the same cornering speed with lower fuel consumption (similar to the examples in my earlier post).
2, If the corner radius is very small and the speed of the "normal" car is limited by the grip of the tyres/downforce (100mph in the example below) (or if the speed of the car is limited by some other outside source such as a safety car or speed limit), then switching to the low drag car he does not have the option of going faster (since the grip is unaffected by the drag), so he has no option but to save fuel. However you can also see from the chart that the fuel consumption that is saved at low cornering speeds is very small compared to higher cornering speeds (or indeed, when the car is accelerating and using the full power of the engine).
This all begs the question:-
"Why do we hear f1 driver's being told to save fuel every race, and why do we see Le Mans cars saving fuel to extend their stint lengths?"
The answer is that the perfect F1 race strategy is one in which the car completes the full race distance with no fuel remaining in the tank* (* except the amount required for post-race scrutineering), since if he finished the race with a lot of fuel in the tank that would mean he were carrying around some extra weight that was detrimental to race performance. The f1 teams try and get this "remaining fuel" amount down as small as possible; they even try and take into account expected safety car periods, and this means they actually under-fuel the car, meaning that the driver is sometimes asked to save fuel by short shifting or lifting off the throttle at the end of straights -but this will reduce his lap speed.
In races that allow refuelling it is quite common for the fuel capacity onboard to be slightly less than required to complete the race distance "flat out". E.g. imagine a situation where a car can complete 99 laps on two tanks of fuel (i.e. one mid-race pitstop) when driven "flat out", but the race distance is 100 laps; clearly it will be more beneficial for the driver to save a little bit of fuel (by reducing his lap speed slightly, hence reducing his fuel consumption, by short-shifting or lifting off the throttle) in order to save a bit of fuel and do 100 laps with just one fuel stop, rather than doing a final "splash and dash" on the penultimate lap.
In both instances the fuel saving is achieved by driving the car slower than the pace that it is capable of doing if it is driven flat out (i.e. the driver is exchanging lap speed for reduced fuel consumption by lifting off the throttle or short shifting), whether it is a "normal drag" car or a "low drag" one.
For the moment congratulations to everyone!
