WhiteBlue wrote:It appears to me that you are not aware of the consequences of your choice. You need 4MJ of ES to be able to qualify competitively. In qualifying you can drive the out lap without power assistance from the ES and use the full 4MJ of the ES for your qualifying lap unless you have compromised the storage capacity as you just proposed. You will be significantly slower in qualifying because your one lap energy budget is 1.21 MJ short of the optimum. There will be competitors who will have full power from using all the energy a four MJ system can store.
The idea here, my dear boy, is to recover energy and use it.
If you can recover 2MJ in a race lap you can certainly recover 2MJ on a qualifying lap.
So, you only actually need to start the lap with 2MJ stored.
Plus, once qualifying starts you are expressly forbidden to charge the system.
5.2.2 Energy flows, power and ES state of charge limits are defined in the energy flow diagram shown in Appendix 3 of these regulations.
When the car is on the track a lap will be measured on each successive crossing of the timing line, however, when entering the pits the lap will end, and the next one will begin, at the start of the pit lane (as defined in the F1 Sporting Regulations).
ES state of charge cannot increase whilst car is in the pit lane or garage during the qualifying session.
Measurements will be taken at the input to and the output from the ES.
A fixed efficiency correction of 0.95 will be used to monitor the maximum MGU-K power.
So, your first flying lap will be with 4MJ in Q1. Thereafter you can only use what you can recover.
If you use the full 4MJ on that first lap, and recover 2MJ that means you will only have 2MJ for the next qualifying lap. After which you will only have 2MJ for qualifying, unless you put 2 or 3 pretty serious laps without using the MGUK to power the car in order to bumpt that 2MJ up to 4MJ.
If you start with 2MJ, use 2MJ and you can recover 2MJ you finish with 2MJ. Then on your last qualifying effort you can start with 2MJ, recover 2 MJ and use 4MJ.
WhiteBlue wrote:That is the lesser evil compared to a reduced power density or a reduced energy density. I have already covered both cases in my original post. Opting for just battery cells and no supercapacitor would be worse than going for a supercap ES only.
I honestly would only be speculating. As you are.
You would need some clever electronics to be able to dump some into a battery and some into a supercapacitor.
I am really not sure how the power density thing works. Are you?
For example, this year's cars can harvest 60kW in the KERS.
Using your numbers - 60kW/(1.1kW/kg) = 54.5kg. Do you really think that they are carrying around 54.5kg of batteries this year and wearing it, considering that the minimum weight was increased to account of the whole KER system by aroun 20kg? Adrian Newey elected to not run KERS in 2009 because h ethought it too heavy - I'm sure he would have thought the same if he had to carry 55kg worth of batteries!
WhiteBlue wrote:I do not know how much you have seen of the race and what commentators you followed. I followed the race on Eurosport with German commentators. They had guests all the time from Audi, Toyota, Porsche, Michelin and from just about everybody who is somebody in LMP racing. I also followed the analysis after Le Mans. It became clear from the experts comment that the Toyota energy recovery system was by far superior to the Audi system. Audi's performance advantage was completely based on their superior top end power generation and their aerodynamic sophistication. Toyota had massively more power to weight ratio in their ES system than Audi had and Audi knew this before January 2013. They had asked the ACO to use a gas accumulator system for ES which was not allowed for some reason by the ACO to cure the problem. There were reports that Audi will come with a new system next year when the rules change and it is unlikely to be the Williams flywheel in its present incarnation. I think the flywheel is too far behind in energy density to be competitive with supercaps.
It's good you include the words "I think".
Fair enough that other factors may have been at play in Audi's superiority at Le Mans.
WhiteBlue wrote:wuzak wrote:WhiteBlue wrote:3. Ultra capacitors by energy density:
15.4 kg * 0.1116 MJ/kg = 1.72 MJ (2.28 MJ still missing)
I don't think you need to have 4MJ capacity.
For example, you cross the start finish line with 4MJ. You use 600kJ on the run down to the first corner, which is the biggest braking zone on the track and can give you 800kJ of your 2MJ braking recovery allowance. But you are only allowed to store 600kJ, so you throw away 200kJ and can't make 2MJ on that lap.
But, if you have 2MJ capacity and store 1MJ then you can use your 600kJ and gain back 800kJ and be ahead, with room to store extra.
So why not just have 25kg of supercapacitors.
(using your numbers) 25kg * 0.1116 MJ/kg = 2.79MJ.
Don't ever actually store more than 2MJ - as you use it as you go. Recover energy in braking zone, use it to assist the ICE to accelerate on the next straight.
It appears to me that you are not aware of the consequences of your choice. You need 4MJ of ES to be able to qualify competitively. In qualifying you can drive the out lap without power assistance from the ES and use the full 4MJ of the ES for your qualifying lap unless you have compromised the storage capacity as you just proposed. You will be significantly slower in qualifying because your one lap energy budget is 1.21 MJ short of the optimum. There will be competitors who will have full power from using all the energy a four MJ system can store.
wuzak wrote:Flywheels are not competitive as I have already pointed out above. Supercaps do not significantly degrade at all.
So you think.
Capacitors do have limited life spans. The life span reduces with high temperatures. It may be more than enough to do a whole season of F1, but then again it might not. Who knows? These things could get seriously hot.
Flywheels are limited by their mechanical components. Which means they have much longer life. Maybe not important in F1 terms.
Bosch made a modular flywheel system. Add capacity - add another module. And flywheels can have energy densities approaching that of batteries.
WhiteBlue wrote:F1 does not specify the energy density or the power density or the physical principle of your ES, but they have defined the capacities and max/min weight of the ES in such a way that it tweaks the rules completely in favour of of a mixed system unless of course someone will come out with an ultracap that raises the bar in energy density to somewhere north of 60 Wh/kg.
You are still aiming for 4MJ. How quaint.
WhiteBlue wrote:I have not been saying that Red Bull is only using 20 kW. The thermal load is calculated by using the time factor build by comparing the use time of all operation with 60 kW with the average lap time. You have roughly 12 s of braking at full power and 8 seconds of KERS push button time. That 20 s is compared to the 95 s of the total average lap time. It gives you the load factor for all KERS machines not only for Red Bull because braking and KERS time is the same for all. The difference is in the over load factor that you decide to use based on that thermal load. My point was that Newey typically cuts it to the bone in cooling capacities and I expect him to be no different in this case. He will rather try to save a few kg of weight and gain performance than allowing a bigger safety margin in thermal layout.
Seriously, what?
Newey would compromise a system so that more often than not it is dead weight?
If it is the same for all KERS equiped cars, then why did you mention the 20s time and 21% "utilisation" factor?
Maybe Newey skimps on cooling a bit, but I doubt very much it is by a factor of 5, as you claim.