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Originally posted by desmo
As Duckworth pointed out years ago, if a maximum fuel flow rate is stipulated, there is really no point in further mandating a displacement limit, number of cylinders, turbo or non etc.. These sorts of restrictions can only impede the goal of increased thermodynamic efficiencies.
It seems like FIA will impose some more restrictions than just fuel flow, this in order to get engine speeds of around 15,000 rpm.
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Originally posted by Wuzak
I guess that depends how much weight is added to the drive train to have turbo-compounding.
An article on the R-3350 suggests recovery of about 20% of the exhaust energy. Maybe with modern technologies more can be attained.
NACA did some tests many years ago. They got something like 15% of the crankshaft power from the turbine. On the other hand, crank power decreased by 5%. This meant a net gain of about 10%.
But the turbine can only be optimized for one or a few conditions. So, as in the case of ordinary automobile engines, where engines are mostly run at part load you will get in trouble. But in F1 where engines are used mainly at full load it might be useful.
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Originally posted by desmo
I understand that. My problem with restrictor plates is that they create a design constraint that has no real world equivalent. No developments for a restrictor plate formula are likely to have any design relevance as intake area is something that is never decreed in the real World. It's as removed from reality as a design constraint as forcing 20,000rpm (or whatever arbitrary rpm limit) displacement limited engines is. Mandatory restrictor plates, arbitrary rpm and displacement limits essentially don't happen outside of racing.
Restricting fuel flow only makes sense if it is technically feasible to do so reliably and easily. The easiest, most enforcable and most robust means of restricting outputs is obviously a simple fuel quantity limit. It has the added benefit of being by far the most closely analogous constraint to real World requirements: How much motive power can be extracted from a given quantity of a given common commercial fuel? Real World cars (arcane tax laws aside) aren't designed around displacement or intake limits, it makes no sense to me to use those artificial constraints when a simpler and ever increasingly relevant means is available. Fuel/thermodynamic efficiency looks to me like the primary driver of automotive powerplant development for the foreseeable future. Why not lead the way in F1 instead of forcing development into another useless direction with few or no potential crossovers for the firms footing the bills?
To limit the fuel flow (energy flow) is technically feasible. Flow fuel is measured using an impeller style flow measuring device (impeller speed detected using a hall effect sensor) with a built in temperature sensor. For returnless systems a single flow measuring device is enough while systems with a fuel return must use two. The flow measureing devices are then connected to the engine control unit. Pi Research / Ricardo who make these devices, which have been used in BTCC for a few years now, claim that they are very accurate and cost about $3000. Each unit has its own serial number and a test certificate.
It seems that FIA also may give certain fuels an advantage based for example well-to-wheel efficiency. In other words, use a fuel that has low net emissions of CO2 and you can get more power.
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Originally posted by mariner
I think this has been pointed out already in the press but any discussion about "green" F1 cars is total hypocracy as long as the teams run wind tunnels 24/7 in search of tiny optimisation gains.
If you did an analysis of the carbon footprint of F1 in say the 1970's versus today the results would be horrific due to the huge growth in team's sizes and budgets. 300 people all sitting at powerful workstations in nice office complexes with one or two wind tuneels out the back are vastly more energy consuming than 30 people with drawaing boards in a single indusrtial unit.
I am not saying that the only answer is nostalgia but as mentioned above a fuel or air restriction formula gets the " green" job done just as well or simply limit the fuel load at say 20% below todayand get on with it.
The suspicious side of my mind notes that a BMW representative was central to one of Max's recent press shows. I wonder if the rules are going to be swung to favour turbo diesels because that is what BMW and Mercedes are the leaders at so they are pulling strings to get something that best suits there own marketing needs.
These regulations are really not about making F1 a "greener" sport, its about making the sport seem greener and to give the manufacturers a possebility to develop technology that is similar to what is used in energy efficient production cars.
I remember that I read somewhere that it took something like four (or was it two?) Boeing 747 cargo planes just to transport all the equipment needed for a F1 race. Even if the teams drove as much as possible during a weekend they would hardly comsume even 10 cubic meters of fuel combined while one of these 747's can comsume 100-200 cubic meters of fuel during long trips.
We can also look at the fuel usage of the teams. Each team use about 200 cubic meters each year, but I suspect that only about 10-20 cubuc meters are used during races while the rest is used for testing. If the goal was to reduce the emissions caused by F1 there are much better ways than trying to improve the efficiency of their powertrains. Examples include no engine development, very little car development, very little testing and fewer international races.
I believe that just the wind tunnels used for aero development cause more CO2 emissions than what the cars do when they race.
Not to mention the emissions caused by all the spectators watching the races...
Fuel efficiency as the cap on engine outputs is best not because it is Green, (although if you put enough lipstick on that pig...) but because it is the most logical, elegant, effective, robust and simple means to do so.
