I was commenting on the idea that one 2014 engine could have 100hp more - and yet still be slower in a straight line.atanatizante wrote:These increased speeds could be due to ? :wuzak wrote:100hp less at 336km/h (Alonso's recorded maximum speed) would require ~12% less drag. Condsidering that the cars are said to be 15% less draggy compared to last year, it is unlikely that one has almost the same improvement against the others.tuj wrote:The Ferrari engine is the most compact laterally and uses an air-water-air intercooler, therefore it can run significantly smaller sidepods, thus reducing drag. Also, don't forget that top speed is often also an indicator of a lack of down-force in F1.
Next top speed was Magnussen at 330km/h. He has the Mercedes engine, supposedly with the 100hp extra. That would suggest the Macca is carrying ~20% more drag.
Seems very unlikely to me.
1. A lower AoA RW main flap
2. A rear wing flap this year is 20mm smaller than last year and therefore the flap is slightly shallower in profile
3. A DRS flap can now open as wide as 65mm, 15mm wider than last year.
4. No beam wing.
Nonetheless, this situation is very interesting coz this year car is 48kg heavier, at least in Qualy trim
and tyres are harder now so therefore car is slower
The 1988 cars were restricted to 150l of fuel. Which is about 113kg, depending on the fuel's density.Wayne DR wrote:I agree. Due to the fuel flow limits, running a lambda of 0.98 (similar to the Honda RA168E) you can only run 2.5 bar to around 11,000RPM. The limit at 12,000 around 2.3 bar, 2.1 bar at 13k, 2 at 14k and less than 1.9 at 15k. Honda's testing on the RA168E showed a drop off in efficiency greater than 18% for boost pressures less than 2.1 bar! You can lean out further, but this also has efficiency and power generation penalties.Abarth wrote:Which is a bit odd, I didn't think they will go much higher than 13/13.5k. I understand that with compounding the friction losses are traded in for less pumping losses/boost requirements and therefore higher MGU-H power harvest to be sent to the MGU-K, therefore improving WOT efficiency. However, I thought there is no point about going all up to 15'000. This also because the broad power band.motobaleno wrote:in the comments on an exclusive interview with vettel autosprint reports that merc engine is revving 14.000 and renault 12.500 so far. also, they implicitly suggest that all the teams are looking for 15.000 despite the decrease in power above 10.500 due to friction...
The other significant factors to note from the 1988 FIA Regulations:
- There was no limit on the ingredients in the fuel (the RA168E ran on a cocktail of 84% Toluene and 16% n-Heptane to get combustion stability)
- The cars were allowed 150kg of fuel per race (although we do have ERS now).
Honda achieved a minimum Brake Specific Fuel Consumption (BSFC) of 272g/kWh on this engine (32.2% efficiency). This was over 25 years ago, and engine management and lubricants have come a long way, and direct injection engines will be inherently more efficient.
The numbers I saw from the Cosworth "still born" V6 project quoted minimum BSFC around 190g/kWh, an efficiency around 40% very impressive but what is the combustion stability of pump fuel at 2.5bar? At 25% Toluene content, Honda found volumetric fuel consumption increased by 14% (BSFC increased by 3.5%). The F14T's "backfiring" in the garage shows they are obviously working on the limit...
I am in awe of what the engine manufacturers have achieved to date!
Sorry, you are right it is 150L, not kgs.wuzak wrote: The 1988 cars were restricted to 150l of fuel. Which is about 113kg, depending on the fuel's density.
That 150l of fuel had to do the race, the out lap (to the grid), the formation lap and the in-lap (back to the pits). And the rules allowed, as now, to do multiple passes through the pits on the way to the grid. Not sure if they were allowed to refuel on the grid - they certainly aren't now.
The 2014 cars are allowed to use a maximum of 100kg from the start of the race (when the lights go out) to the chequered flag. Roughly a 13kg reduction in fuel usage after 25 years shouldn't be beyond the realms of possibility.
Also, F1 fuel may share many of its ingredients with "pump fuel", but it is not in fact "pump fuel" and is highly tailored to the task.
If time is in seconds then it must be kilos both sides of the =. So kiloWatts & kiloJoulesDel Boy wrote:I don't think you fully understand joules? The joule is the same as a watt second. That means that the MGUK can produce 120 kilowatts for 33 seconds 120 x 33.3= 3,996 or just about 4MJ. The MGUK can only produce 120 kilowatts (160 hp) but 4 mega joules it can take from the ES has a time limit 33.3 seconds. Or if you reduce the watts you can increase the time. Here is the formulaMaxion wrote:They're not limited to 33s. They're limited to 120KW from the MGU-K and 2MJ from the ES. This year, since they don't have a KERS button, the MGU-K will apply it's power as part of the engine mapping. The teams will probably not use it as a "turbo boost" but rather use the MGU-K to improve acceleration and to make the PUs' torque curve flatter.ringo wrote:The cars don't look as zippy to me. They have the electric torque for 33s and the gearing and the low downforce body and pirelli tyres. The truth about the top speeds is somewhere in the middle of that.
Time x kiloWatts = megajoules
Edited to kilowatts thanks to Dren my mistake typo
This is the only graph from Cosworth which I question, not quantitatively but qualitatively.ringo wrote:[....]The power does drop after the fuel limit peaks. Well according to theory, however the cosworth engine graphs show otherwise.[...]
Could it be that Cosworth are reporting the standalone ICE power as if the mgu-h were attached, and just not counting the extra 120 kw?Abarth wrote:This is the only graph from Cosworth which I question, not quantitatively but qualitatively.ringo wrote:[....]The power does drop after the fuel limit peaks. Well according to theory, however the cosworth engine graphs show otherwise.[...]
And they do contradict themseves with the BSFC graph, where they show the BSFC of the engine without MGU-H, reaching a best point of approx. 225 g/kWh @ 9'000/min and then raising all up until >260g / kWh @ 15'000/min.
If you use all the allowed fuel flow, max. performance must be at around 10'500 / min with these BSFC numbers.
With compounding, cou can use the almost constant exhaust mass flow above 10.5k. The higher you are revving, the less you need for compressing the charge air and therefore you use it for electrical power generation.
In that case, Cosworth calculates a best point of approx. 190 g /kWH @ 12'000/min.
With a fuel having 45.5 MJ/kg, this results in an efficiency of around 41.5%.
Thinking aloud here, the more efficient you can make the ICE at higher rpm the better. Ideally if you manage to achieve the same efficiency at 15k as at 10k then you are still using the same amount of fuel (as it is fixed) to make the same amount of power from the ICE, however you will have far more "excess boost" which will show itself as MGU-h regeneration -> mgu-k power.Abarth wrote:Which is a bit odd, I didn't think they will go much higher than 13/13.5k. I understand that with compounding the friction losses are traded in for less pumping losses/boost requirements and therefore higher MGU-H power harvest to be sent to the MGU-K, therefore improving WOT efficiency. However, I thought there is no point about going all up to 15'000. This also because the broad power band.motobaleno wrote:in the comments on an exclusive interview with vettel autosprint reports that merc engine is revving 14.000 and renault 12.500 so far. also, they implicitly suggest that all the teams are looking for 15.000 despite the decrease in power above 10.500 due to friction...
Conventional thinking would suggest that the addition of a turbo would require a lower CR but with DI being allowed, perhaps the CR has stayed the same or even increased?The BMW paper tells us that the E41/4 had a bore of 94.0 mm, and with four titanium valves per cylinder it had 40.5 mm intake and 31.2 mm exhaust valves. BMW used compound valve angles throughout but the valve angles remain undisclosed. The timing drive was always at the front of the engine. Valve operation used finger cam followers, and intake valve lift was in the region of 16 mm. Throughout, the compression ratio was in the region of 14.5-15.0:1.
Usually stratified charge is used to improve part load efficiency.tuj wrote:[...]if above 10k they could run a lean but stratified charge to prevent knock. Supposedly stratified charge engines have been developed with CR's as high as 20:1 running normal petrol. [...]
You do not believe in 650 bhp from the engine?ringo wrote:sorry if it's beating a dead horse with my power graphs.
But i've done some refinements calculation wise. It's a bit bumpy around the 10,000 to 11,000rpm mark because i didn't include the 10,500rpm point. I just wanted 1,000rpm increments for expedience.
http://i1010.photobucket.com/albums/af2 ... 6138ae.png
The power does drop after the fuel limit peaks. Well according to theory, however the cosworth engine graphs show otherwise.
What i do notice though with my calculations is that reducing the fuel pressure does have positive effects on the power output in some cases. Maybe direct injection is a different case. But yeah, the teams can also manipulate that as well.