911 GT3 R Hybrid
Discussion
Does anyone know if the flywheel is always turning , or does it only turn when breaking and when accelerating (with the button pushed)?
If it is the latter, then the gyroscopic effects on handling would be minimized as most (hard )breaking and acceleration is done whilst the car is straight and not turning (or when the button is pushed)
If it is the latter, then the gyroscopic effects on handling would be minimized as most (hard )breaking and acceleration is done whilst the car is straight and not turning (or when the button is pushed)
slivka said:
Does anyone know if the flywheel is always turning , or does it only turn when breaking and when accelerating (with the button pushed)?
If it is the latter, then the gyroscopic effects on handling would be minimized as most (hard )breaking and acceleration is done whilst the car is straight and not turning (or when the button is pushed)
if it's not spinning, then no energy stored....If it is the latter, then the gyroscopic effects on handling would be minimized as most (hard )breaking and acceleration is done whilst the car is straight and not turning (or when the button is pushed)
you brake into a corner, so if you want to have energy available to pull out of said corner, mid-corner the flywheel will be at peak rpm
JonnyVTEC said:
On the Z - axis is will help to control pitching and roll.
i dont think so. when you brake the car will pitch forward and the flywheel will roll the car, left or right depending on rotation. similarly when you corner and the car rolls the flywheel will be trying to pitch the car forward or back. i dont think it 'helps control' handling at all. would be interesting to see what size the forces are if anyone can remeber the maths?Scuffers said:
Graham E said:
gyro experst - coutld they run it asdual chamber, counterrotating? would that solve the balance issue?
that would solve the torque reaction issues, but not the gyroscopic ones...I don't want to labor a point, but what do you guys make of this:
"The system is comprised of an electrically driven flywheel and a motor/generator on the gearbox. During braking the gearbox mounted generator drives the flywheel to spin it up to 40,000 rpm. When needed for extra acceleration, the flywheel drives its integrated motor/generator to spin provide power back to the unit on the gearbox."
To the untrained and non-techie eye like mine, this sounds like the flywheel only spins when braking and accelerating (with button pushed).
"The system is comprised of an electrically driven flywheel and a motor/generator on the gearbox. During braking the gearbox mounted generator drives the flywheel to spin it up to 40,000 rpm. When needed for extra acceleration, the flywheel drives its integrated motor/generator to spin provide power back to the unit on the gearbox."
To the untrained and non-techie eye like mine, this sounds like the flywheel only spins when braking and accelerating (with button pushed).
slivka said:
I don't want to labor a point, but what do you guys make of this:
"The system is comprised of an electrically driven flywheel and a motor/generator on the gearbox. During braking the gearbox mounted generator drives the flywheel to spin it up to 40,000 rpm. When needed for extra acceleration, the flywheel drives its integrated motor/generator to spin provide power back to the unit on the gearbox."
To the untrained and non-techie eye like mine, this sounds like the flywheel only spins when braking and accelerating (with button pushed).
It's quite a simple system really:"The system is comprised of an electrically driven flywheel and a motor/generator on the gearbox. During braking the gearbox mounted generator drives the flywheel to spin it up to 40,000 rpm. When needed for extra acceleration, the flywheel drives its integrated motor/generator to spin provide power back to the unit on the gearbox."
To the untrained and non-techie eye like mine, this sounds like the flywheel only spins when braking and accelerating (with button pushed).
Under braking, the electric motors / dynamos (one and the same really) on the front axles send power to the motor on the flywheel.
This motor spins the flywheel, in effect transferring the kinetic energy from braking into kinetic energy in the flywheel, via 2 motors. The flywheel in effect has "power"* stored in it from braking.
Upon acelerating, the spinning mass of the flywheel is used to turn the flywheel drive motor - which now acts as a dynamo. This sends electrical power to the drive motors on the front axles, in effect transferring the kinetic energy of the flywheel to kinetic energy driving the car forwards.
In the system above, the flywheel is simply storing the energy so it can be used later (i.e store on brake, release on throttle). This is just an alternative to using a battery - a battery would replace the drive motor on the flywheel and the flywheel itself. IMO a battery would be heavier though.
- For the PH pedants, I am aware that that should say "energy", not "power". I just thought it read better that way.
fbrs said:
Scuffers said:
Graham E said:
gyro experst - coutld they run it asdual chamber, counterrotating? would that solve the balance issue?
that would solve the torque reaction issues, but not the gyroscopic ones...slivka said:
I don't want to labor a point, but what do you guys make of this:
"The system is comprised of an electrically driven flywheel and a motor/generator on the gearbox. During braking the gearbox mounted generator drives the flywheel to spin it up to 40,000 rpm. When needed for extra acceleration, the flywheel drives its integrated motor/generator to spin provide power back to the unit on the gearbox."
To the untrained and non-techie eye like mine, this sounds like the flywheel only spins when braking and accelerating (with button pushed).
Answer this question then, you have just braked down form silly speed to a corner, so:"The system is comprised of an electrically driven flywheel and a motor/generator on the gearbox. During braking the gearbox mounted generator drives the flywheel to spin it up to 40,000 rpm. When needed for extra acceleration, the flywheel drives its integrated motor/generator to spin provide power back to the unit on the gearbox."
To the untrained and non-techie eye like mine, this sounds like the flywheel only spins when braking and accelerating (with button pushed).
"During braking the gearbox mounted generator drives the flywheel to spin it up to 40,000 rpm"
right, you take your foot off the brakes, the flywheel will still be spinning at 40,000Rpm.
only thing that's going to stop it spinning is when you have recovered *all* the kinetic energy stored in said flywheel, else it will continue to spin indefinitely (apart from whatever friction is in the system slowing it down).
what you seem to be missing is that it;s the spinning of the flywheel that's the energy storage part of the system.
in reality, it's going to be spinning *all* the time, all be it at different speeds.
Edited by Scuffers on Tuesday 16th February 13:42
Graham E said:
In the system above, the flywheel is simply storing the energy so it can be used later (i.e store on brake, release on throttle). This is just an alternative to using a battery - a battery would replace the drive motor on the flywheel and the flywheel itself. IMO a battery would be heavier though.
The only reason I can see for using the flywheel rather than the battery in this particular configuration would be higher energy / weight than a battery. But I don't think it stacks up too well compared to modern battery technology, or things like super caps.- For the PH pedants, I am aware that that should say "energy", not "power". I just thought it read better that way.
A few decent sized Li-Ion battery packs could get you 1MJ (thats about 2.4Ah at 120V). Rapid discharge and charge might be complicated, and the control electronics would need to be good but you'll have to have some amount of complicated control electronics not to overspeed the flywheel and control the motors anyway.
I guess its designers sticking to what they know, but the mech/elec mish-mash is the confusing bit...
Still its good to see companies trying out new technologies in the real world of racing.
Scuffers said:
fbrs said:
Scuffers said:
Graham E said:
gyro experst - coutld they run it asdual chamber, counterrotating? would that solve the balance issue?
that would solve the torque reaction issues, but not the gyroscopic ones...
Edited by fbrs on Tuesday 16th February 15:30
fbrs said:
Scuffers said:
fbrs said:
Scuffers said:
Graham E said:
gyro experst - coutld they run it asdual chamber, counterrotating? would that solve the balance issue?
that would solve the torque reaction issues, but not the gyroscopic ones...Edited by fbrs on Tuesday 16th February 15:30
renrut said:
Erm wouldn't that spin the car without the grip of the tyres to change the direction of its momentum? Sounds like a fun gadget guaranteed to make your passengers puke
not really. with zero grip spinning or mid air or ice, whatever, the car will keep traveling in the same direction but you could control the angle. if the car is over or understeering, braking one flywheel or the other would exert a torque on the car to control it like dsc/esp do braking one wheel. i was thinking of it more as stability control.Edited by fbrs on Tuesday 16th February 16:02
fbrs said:
renrut said:
Erm wouldn't that spin the car without the grip of the tyres to change the direction of its momentum? Sounds like a fun gadget guaranteed to make your passengers puke
not really. with zero grip spinning or mid air or ice, whatever, the car will keep traveling in the same direction but you could control the angle. if the car is over or understeering, braking one flywheel or the other would exert a torque on the car to control it like dsc/esp do braking one wheel. i was thinking of it more as stability control.Edited by fbrs on Tuesday 16th February 16:02
Being serious I do know what you mean but still can't see the benefit of it. I'd imagine they'd have to be fairly big and require a lot of power to alter their relativistic spins, and by saving that weight you could make a lighter more nimble car. Still, it's be interesting to see it, maybe on an ICE RC car as a demo?
renrut said:
Ah gotcha. So you still slide off the road but can choose if you go off forwards or backwards? Cool.
Being serious I do know what you mean but still can't see the benefit of it. I'd imagine they'd have to be fairly big and require a lot of power to alter their relativistic spins, and by saving that weight you could make a lighter more nimble car. Still, it's be interesting to see it, maybe on an ICE RC car as a demo?
haha. presisely! seriously i imagine it could work in tandem with esp/dsc to control on the limit not nesesarliy to decide what shape hole to leave in the hedge. Being serious I do know what you mean but still can't see the benefit of it. I'd imagine they'd have to be fairly big and require a lot of power to alter their relativistic spins, and by saving that weight you could make a lighter more nimble car. Still, it's be interesting to see it, maybe on an ICE RC car as a demo?
regarding size the reason flywheels are interesting is the huge amount of energy they can store for their own weight (10x batteries i read somewhere) and the speed they can be (dis)charged. the mechanism for braking or accelerating them is already there; the motor/dynamo.
got to say this http://www.flybridsystems.com/F1System.html looks like a far more efficient/elegant solution than all these electric motors and dynamos
Edited by fbrs on Wednesday 17th February 15:26
renrut said:
The only reason I can see for using the flywheel rather than the battery in this particular configuration would be higher energy / weight than a battery. But I don't think it stacks up too well compared to modern battery technology, or things like super caps.
A few decent sized Li-Ion battery packs could get you 1MJ (thats about 2.4Ah at 120V). Rapid discharge and charge might be complicated, and the control electronics would need to be good but you'll have to have some amount of complicated control electronics not to overspeed the flywheel and control the motors anyway.
I guess its designers sticking to what they know, but the mech/elec mish-mash is the confusing bit...
Still its good to see companies trying out new technologies in the real world of racing.
Personally, having looked at a mobile phone Li-ion battery:A few decent sized Li-Ion battery packs could get you 1MJ (thats about 2.4Ah at 120V). Rapid discharge and charge might be complicated, and the control electronics would need to be good but you'll have to have some amount of complicated control electronics not to overspeed the flywheel and control the motors anyway.
I guess its designers sticking to what they know, but the mech/elec mish-mash is the confusing bit...
Still its good to see companies trying out new technologies in the real world of racing.
Carged daily, emptied daily. Thats 365 charges a year. I'm yet to see a mobile battery last 2 years and still be "useful" (this might be engineered in, but hey). We'll call a Nokia battery useless after 2 years, or 730 cycles.
Take Le Mans: 11 braking zones / accelerations of note per lap. 382 laps. Thats 4202 cycles, or 11.5 years for our Nokia battery.
I would be very impressed if a system could charge / discharge this amount (without overheating) this many times - a large capacator might be more suitable? (I'm no spark though, I have no idea how big / faesable a 1MJ capacator would be).
With a flywheel, IMO you're essentially looking at centrifuge technology. There are many (scarily many) machines in the UK scientific sector that are over 30 years old, and run to 40k RPM with a load of 4 litres or more. The stainless steel rotors for these old units are massively heavy, so in total way in excess of what you'd be looking at for Williams' application. The braking from 40k RPM is also done electromagnetically via the motor - the same as in the Williams design.
If people could do this 30 years ago (that lasts for 30 years), then I'm pretty confident that todays technology could handle the demands pretty easily - overspeed is easy (just cut electrical power to drive at 39.5k RPM, etc), and mdern centrifuges (which are made for science, not for fastest accel / decel) can come from 40k to a complete stop in about 2 minutes, without getting the sample over a certain rate of deceleration, which would "undo" the seperation of a fuge. Without that control, 40k - 20k rpm could be very, very rapid indeed.
The thing that I'd be really interested to read about is the gyroscopic effect people have been mentioning. I know very little about gyroscopes, other than having one as a kid, and sort of understanding their applications on ships. Could any of you gyroscopically minded people explain what impact a 'scope would have on a car? Is it just the resistance to roll that would be created by the spinning disc? Would it give extra effective forward momentum (you can spot the non physicist here easily). Alternatively, a link would also be appreciated =)
Ta
G
Graham E said:
Personally, having looked at a mobile phone Li-ion battery:
Carged daily, emptied daily. Thats 365 charges a year. I'm yet to see a mobile battery last 2 years and still be "useful" (this might be engineered in, but hey). We'll call a Nokia battery useless after 2 years, or 730 cycles.
Take Le Mans: 11 braking zones / accelerations of note per lap. 382 laps. Thats 4202 cycles, or 11.5 years for our Nokia battery.
I would be very impressed if a system could charge / discharge this amount (without overheating) this many times - a large capacator might be more suitable? (I'm no spark though, I have no idea how big / faesable a 1MJ capacator would be).
Phone battery's are not designed for this job, so it's hardly a surprise they would not last long doing something they are not made to do.Carged daily, emptied daily. Thats 365 charges a year. I'm yet to see a mobile battery last 2 years and still be "useful" (this might be engineered in, but hey). We'll call a Nokia battery useless after 2 years, or 730 cycles.
Take Le Mans: 11 braking zones / accelerations of note per lap. 382 laps. Thats 4202 cycles, or 11.5 years for our Nokia battery.
I would be very impressed if a system could charge / discharge this amount (without overheating) this many times - a large capacator might be more suitable? (I'm no spark though, I have no idea how big / faesable a 1MJ capacator would be).
in the old days, you would use super-capacitors for this kind of job, high current capacity, low storage timeframes - unlike a battery.
there are quite a few companies now working on battery's that can deal with the loads of a KERS type setup, people like http://www.a123systems.com/ with their nano-phosphate battery's.
not sure how these would stack up capacity/KG though compared with a flywheel based storage system?
Scuffers said:
Phone battery's are not designed for this job, so it's hardly a surprise they would not last long doing something they are not made to do.
Too bloody right - the cynic in me thinks phone batteries are designed specifically to be as useful as dale winton in a fight after 12 months, meaning you have to upgrade the thing every bloody year. Except now we all have 18 month contracts, it means you need to buy a new battery, THEN upgrade it ever 1.5 years. Vagabonds!
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