KERS as engine starter? [Archive]

ioan

14th February 2009, 11:50

Did you think of that yourself ioan or find it on a forum? In any case that's the first time I've heard it and I think its genius. :up:

I've been wondering about this since the Ferrari was launched and the first info about the KERS set-up were known.

Besides here I only post in another F1 related forum, the F1M which is about modeling but people have great in depth technical knowledge about f1 cars from all eras, but I didn't read about it anywhere else, so iI thought that I'll start a thread in my favorite forum. :D

I have a doubt that using KERS to start the engine might be strictly forbidden, but I didn't yet take my time to read through the whole technical regulations.

SteveA

14th February 2009, 12:32

I'm not sure if it would be easier to do it by using the electrical engine to move the car or to use the KERS batteries to directly start V10, but it is certainly doable.

I should think using the KERS motor to bump-start the car in gear would be enough. I don't expect they want the extra weight of a separate starter motor.

ioan

14th February 2009, 15:01

I should think using the KERS motor to bump-start the car in gear would be enough. I don't expect they want the extra weight of a separate starter motor.

I always thought they have a stater motor but they don't have a strong enough, build in, energy source, thus they had to use those manual starters on the grid and in the pits.

K-Pu

16th February 2009, 10:00

A nice idea, but we will see if it is allowed. Anyway, sounds great!

Knock-on

16th February 2009, 10:57

Where does KERS apply energy is the question. I would have thought that if it applies energy to the engine drive then you could use stored energy to restart it. However, I understood that it's the drivetrain and bumping a car in gear is a different matter.

However, it's a moot point these days as cars very rarely stall with the current SW regulations.

Mark

16th February 2009, 11:12

ioan

16th February 2009, 11:59

Where does KERS apply energy is the question. I would have thought that if it applies energy to the engine drive then you could use stored energy to restart it. However, I understood that it's the drivetrain and bumping a car in gear is a different matter.

As far as I know a good number of cars have the KERS electrical engine installed under the fuel tank. I assume the easiest way to use it is connecting it directly to the engine given that the gearbox is on the other side of it.

Knock-on

16th February 2009, 12:17

As far as I know a good number of cars have the KERS electrical engine installed under the fuel tank. I assume the easiest way to use it is connecting it directly to the engine given that the gearbox is on the other side of it.

Must admit, I don't know too much about all the different KERS systems.

Mechanical KERS recovers energy from the transmission during braking and feeds it back in under accelleration. Certainly, this method (the one favoured by the FIA) would be innefective for starting an engine.

With the battery KERS, it depends how they want to set it up. Doesn't Ferrari have their stored in the Nose section?

ioan

16th February 2009, 12:35

I would have thought the extra weight required for a mechanism to allow the engine to start would be enough to prevent the teams from doing it.

Anyway I believe starting an F1 engine is not just a simple matter of spinning it with the ignition on.

Didn't they already have a starter engine built in? I mean until now we only saw the guy with the portable battery that connects to the rear of the car in order to power it up in the case the engine stops.

ioan

16th February 2009, 12:42

With the battery KERS, it depends how they want to set it up. Doesn't Ferrari have their stored in the Nose section?

They were planing to have the batteries stored in the front wing, they even went as far as having a study done by one of NASA suppliers, but as far as I know they gave up on it.
Still it is possible for the teams using electrical KERS to store the batteries in the nose cone given that it would help them move some weight on the forward axle, but I think it needs lots of cooling.

From what I have seen until now, Ferrari, McLaren and other teams too does have the KERS batteries stored in the sidepods. You can see those air intake holes under the main sidepod intakes, these are for cooling the batteries. I saw somewhere a picture taken during last weeks test in Bahrain where cooling ducts were introduced into those holes while the car was in the garage between two stints.

Knock-on

16th February 2009, 12:46

ioan

16th February 2009, 12:53

I didn't think that cars have starter motors. They would have a small Battery for maintaining vital systems but are normally started by a starter motor pushed straight into the back.

I always wondered about what that thing they connect to the back end of the car was. And I always assumed it was some kind of battery, as I doubt that a person could withstand the torque needed to start a 3 liters engine. There is a chance that it is a starter motor and that they do it through the gearbox and because of use of a certain reduction coefficient the torque needed is not that big.

I'll try to get some answers to these questions today. :)

Knock-on

16th February 2009, 12:58

I always wondered about what that thing they connect to the back end of the car was. And I always assumed it was some kind of battery, as I doubt that a person could withstand the torque needed to start a 3 liters engine. There is a chance that it is a starter motor and that they do it through the gearbox and because of use of a certain reduction coefficient the torque needed is not that big.

I'll try to get some answers to these questions today. :)

You don't need to dig too much if you want to take my word for it ;)

You MUST have a seperate starter for the pits and grid and it IS the long thing they stick up the gearbox. It normally works OK but sometimes you have a car stuck in gear that must be started with the rear wheels spinning and drop the thing to get it going.

I don't know exactly how the starter motors work but there could be a spline that slots in to ensure it doesn't twist.

Mark

16th February 2009, 13:03

No, the cars don't have onboard starters, they would be too heavy to carry around when 99.9% of the time you don't need them. Especially with the modern anti-stall technology

Knock-on

16th February 2009, 13:03

http://www.f1technical.net/features/2267

Here you go.

ioan

16th February 2009, 13:11

I don't know exactly how the starter motors work but there could be a spline that slots in to ensure it doesn't twist.

I think you are right there and the solution is really simple, plus I think that on the rare ocassions when they use that thing to start cars during pit stops there was distinct noise coming from it. Not sure cause it is so rare nowadays that I have to base this on distant memories.

So they didn't have a starter motor.
Now they have one in the electrical KERS units. I'll go dig up the rules tonight and see if it's explicitly prohibited to use it to restart a stalled engine.

Any of you know if use of KERS is prohibited during the start (as it could have used as TC) or the cooling demands make its use improbable at such moment (cars standing still for 10 seconds or so)?

ioan

16th February 2009, 13:15

http://www.f1technical.net/features/2267

Here you go.

Thanks, great piece of info :thumbsup:, I'll have to improve my googleing skills. :/

This part is what I was after and clears it all:

[quote="f1technical.net"]"Because the motor has such a kick in it, there is a reaction arm which hooks up on to the rear wing to stop it coming out of the mechanic&#8217]

Knock-on

16th February 2009, 13:43

Thanks, great piece of info :thumbsup:, I'll have to improve my googleing skills. :/

This part is what I was after and clears it all:

Also:

5.15 Starting the engine :
A supplementary device temporarily connected to the car may be used to start the engine both on the grid
and in the pits.
5.16 Stall prevention systems :
If a car is equipped with a stall prevention system, and in order to avoid the possibility of a car involved in
an accident being left with the engine running, all such systems must be configured to stop the engine no
more than ten seconds after activation.

http://argent.fia.com/web/fia-public.ns ... %20Sum.pdf (http://argent.fia.com/web/fia-public.nsf/E280B4702B22A1E9C125753C0056FF76/$FILE/Formula%20One%20Technical%20regulations%20Sum.pdf)

In fairness, it says what may be used, but not what may not :rolleyes:

In theory, there is a potential loophole that will allow a KERS to start an engine but would it really be worth it?

ioan

16th February 2009, 17:39

http://argent.fia.com/web/fia-public.ns ... %20Sum.pdf (http://argent.fia.com/web/fia-public.nsf/E280B4702B22A1E9C125753C0056FF76/$FILE/Formula%20One%20Technical%20regulations%20Sum.pdf)

In fairness, it says what may be used, but not what may not :rolleyes:

In theory, there is a potential loophole that will allow a KERS to start an engine but would it really be worth it?

You bet it's worth it, especially now that championships are won by 1 point.

Thanks for looking it up. :up: :)

Sleeper

16th February 2009, 22:32

I always thought they have a stater motor but they don't have a strong enough, build in, energy source, thus they had to use those manual starters on the grid and in the pits.

As far as I know, no on board starter motor, the manuel starters turn over the gearbox to get it started. Problem is, starting an F1 car on the grid and in the garage requires an army of lap tops and technicians, so I'm not sure whether its do-able due to electronics and software, rather than mechanical requirments.

blito

16th February 2009, 22:54

Some interesting points here - especially the posts claiming that F1 engines are still 3.0 Litre V10`s ( is Ioan REALLY stuck in 2005?? ) but, TBH this post is a little bit on the pointless side as all F1 engines are fitted with anti-stall devices that kick the clutch plates open should the drivetrain resistance overcome the available output torque - ie a car coming to a stop in top gear :o

schmenke

17th February 2009, 21:42

They were planing to have the batteries stored in the front wing, they even went as far as having a study done by one of NASA suppliers, but as far as I know they gave up on it.
Still it is possible for the teams using electrical KERS to store the batteries in the nose cone given that it would help them move some weight on the forward axle, but I think it needs lots of cooling.....

I always thought that engineers strived to eliminate mass from the vehicle's extremities, e.g. front and rear, to improve handling (reduces the polar moment of inertia for you techno-geeks).

Besides, what would happen if the wing needed replacement during a race? :mark:

ioan

17th February 2009, 21:55

I always thought that engineers strived to eliminate mass from the vehicle's extremities, e.g. front and rear, to improve handling (reduces the polar moment of inertia for you techno-geeks).

It seems that because of the KERS engine being situated towards the rear of the car the CoG of the cars has moved further behind than the optimum.
Also it was reported that in order to get the new front tires to work optimally more weight is needed on the front axle.
Because of the introduction of KERS they have less ballast weight at disposal than in the previous years and many teams considered having the KERS batteries in the nose cone.
Ferrari's idea to have them in the front wing was extreme but it would provided a much lower positioning of the weight.

Besides, what would happen if the wing needed replacement during a race? :mark:

Well... they change it! :p :
Having connector pins on the nose cone that lock into sockets situated on the monocoque shouldn't be so complicated at F1 level.

The problem is rather the huge costs and also what happens if they have an accident and the driver or someone else gets some electro-shocks from those cables running from the nosecone towards the back of the car.

ioan

17th February 2009, 21:57

As far as I know, no on board starter motor, the manuel starters turn over the gearbox to get it started. Problem is, starting an F1 car on the grid and in the garage requires an army of lap tops and technicians, so I'm not sure whether its do-able due to electronics and software, rather than mechanical requirments.

It seems that he laptops and technicians are needed only when the engine is cold and parameters like oil temperature need to be optimal. Shouldn't be a problem for a just stalled engine.

ioan

17th February 2009, 22:00

Some interesting points here - especially the posts claiming that F1 engines are still 3.0 Litre V10`s ( is Ioan REALLY stuck in 2005?? )

Maybe Ioan is stuck in 1996! :rolleyes:

but, TBH this post is a little bit on the pointless side as all F1 engines are fitted with anti-stall devices that kick the clutch plates open should the drivetrain resistance overcome the available output torque - ie a car coming to a stop in top gear :o

Still engines stall occasionally and I don't remember a season when that didn't happen at least once.

SGWilko

17th February 2009, 22:26

It seems that he laptops and technicians are needed only when the engine is cold and parameters like oil temperature need to be optimal. Shouldn't be a problem for a just stalled engine.

When these engines are cold, the friction alone* makes them almost impossible to turn, such are the close tolerances. Heated oil has to be pumped round the engine to get it close to the lower range of operating temperature.

*It is entirely possible I am talking cobblers, but I swore I read that somewhere.

blito

17th February 2009, 22:42

nah, thats totally correct Wilko, i remember on Top Gear when Hammond had a "play" with a Renault F1 he spoke about exactly that.

call_me_andrew

18th February 2009, 08:13

Here's a thought: Why would an F1 engine stall? The PCM has a fail safe device and if revs, wheel speed, and throttle position read below a certain threshold the gear box automatically shifts to neutral. The only time an engine could stall is on the grid. And it'll probably be one of those problems that requires an army of laptops to solve.

ioan

18th February 2009, 10:03

Here's a thought: Why would an F1 engine stall?

Because nothing is perfect?

ioan

18th February 2009, 10:05

When these engines are cold, the friction alone* makes them almost impossible to turn, such are the close tolerances. Heated oil has to be pumped round the engine to get it close to the lower range of operating temperature.

That is pretty much possible.
Do they heat the parts in order to mount the engine?

Interesting points are being raised here. Thanks for everyone's input.

jjanicke

20th February 2009, 01:57

The reason it takes an army of people and cpu's to start an F1 engine is as Ioan states. The tolerances are so tight that a cold engine is actually seized up. It's the hot coolant and oil run thru the engine, and a whole slew of controls, that allow it to start up.

One post asks why restart the engine as the all have anti stall devices. Well... we've seen how effective these devices are with numerous stalls on the grids, and the famous Schumi stall during his Monaco qual run.

I would assume the limitations to using the KERS engine to restart the engine is the actual location within the drivetrain (not physical location but functional location). If the KERS engages the wheels after the gearbox/clutch you couldn't use the KERS to start the engine as it would simultaneously drive the wheels while it started the engine. The clearly wouldn't work on the starting grid and probably lead to issues in other circumstances (i.e. beach the car in a run-off)

However if there is a way to use the KERS engine to turn the V8 with the drive shafts disengaged (i.e. the clutch) it would theoretically be possible.

Let's see what happens in '10.

jjanicke

20th February 2009, 02:01

That is pretty much possible.
Do they heat the parts in order to mount the engine?

Interesting points are being raised here. Thanks for everyone's input.

It's not the mounting points that have the ubertight tolerances. It's the running gear within the engine (i.e. piston - cylinders, etc)

Rollo

20th February 2009, 05:43

I didn't think that cars have starter motors. They would have a small Battery for maintaining vital systems but are normally started by a starter motor pushed straight into the back.

There is some ambiguity (well, it is the FIA ;) ) that says a seperate starter must be used in the Pits or Grid but nothing about out on track apart from an automatic cut-off of the engine anti-stall after 10 sec.

http://argent.fia.com/web/fia-public.ns ... %20Sum.pdf (http://argent.fia.com/web/fia-public.nsf/E280B4702B22A1E9C125753C0056FF76/$FILE/Formula%20One%20Technical%20regulations%20Sum.pdf)

Article 5:15 of the Tech Regs states:
5.15 Starting the engine :
A supplementary device temporarily connected to the car may be used to start the engine both on the grid and in the pits.

I note the use of the word "may"; I don't think that that rules out the possibility per se.

5.16 does indeed state that to prevent a car involved in an accident being left with the engine running, all such systems must be configured to stop the engine no more than ten seconds after activation, it doesn't rule out the possibility of an internal system on track.

they would be too heavy to carry around when 99.9% of the time you don't need them. Especially with the modern anti-stall technology

That's the reason why they don't currently have a starter motor and probably why they'll most likely not have one in the future, but because the regulations don't expressly forbid it, I think it would be possible, but the associated weight disadvantage might rule it out.

ioan

20th February 2009, 10:58

It's not the mounting points that have the ubertight tolerances. It's the running gear within the engine (i.e. piston - cylinders, etc)

That's not what I meant, now I see that I should have said "assemble the engine", as mounting was the wrong term to use.

ioan

20th February 2009, 11:01

I would assume the limitations to using the KERS engine to restart the engine is the actual location within the drivetrain (not physical location but functional location). If the KERS engages the wheels after the gearbox/clutch you couldn't use the KERS to start the engine as it would simultaneously drive the wheels while it started the engine. The clearly wouldn't work on the starting grid and probably lead to issues in other circumstances (i.e. beach the car in a run-off)

However if there is a way to use the KERS engine to turn the V8 with the drive shafts disengaged (i.e. the clutch) it would theoretically be possible.

Let's see what happens in '10.

Most of the systems (the Ferrari one for example) are located under the fuel tank, just in front of the engine, and are they are directly connected to the the engine. So it should be possible as soon as the driver engages neutral.

Rollo

22nd February 2009, 21:49

jjanicke

22nd February 2009, 22:18

Does anyone know how much torque is required to start and F1 car? I suspect that due to the fact that the car throw so much torque through the transmission, then the componentry is built mighty heftily; as such would require a massive starter motor... hence the reason why they're not on board in the first place and why they'll continue not to be on board in the future.
... but I still don't see why it shouldn't rule out the use of KERS, it's just impracticable.

Actually F1 engines do not generate a lot of torque. Surprisingly your modern sports car V8 produces more, in some cases a lot more, torque than F1 engines. i read a stat that the modern V8 F1 engine produces something like 292 N-m of torque, about 216 lbs-ft. HP is a factor of torque and RPM. These engines produce so much HP because their usable range is some 15,000 RPM higher than your normal V8.

So I don't think the torque of the starter motor is going to be a factor.

call_me_andrew

23rd February 2009, 04:15

Just because an engine doesn't produce a lot of torque, there's no reason why it wouldn't take a lot to start. I'm sure the engines have a lot of compression to overcome.

ioan

23rd February 2009, 14:37

Does anyone know how much torque is required to start and F1 car? I suspect that due to the fact that the car throw so much torque through the transmission, then the componentry is built mighty heftily; as such would require a massive starter motor... hence the reason why they're not on board in the first place and why they'll continue not to be on board in the future.
... but I still don't see why it shouldn't rule out the use of KERS, it's just impracticable.

The engine components are in fact quite small and slim in order to minimize inertia, the same goes for the gearbox. But still those components are very strong due to use of material with excellent mechanical properties and also to shell machining.

The torque isn't as high as you would expect but that is fairly normal for a rather small (2.4 liter) very high revving (18k ATM) engine.

Knock-on

23rd February 2009, 15:02

The engine components are in fact quite small and slim in order to minimize inertia, the same goes for the gearbox. But still those components are very strong due to use of material with excellent mechanical properties and also to shell machining.

The torque isn't as high as you would expect but that is fairly normal for a rather small (2.4 liter) very high revving (18k ATM) engine.

This all seems rather complicated for my liking.

1. Starting from cold. Forget it. As has been said, a F1 engine is siezed in cold mode and has Oil and all sorts pumped around to get it started. Makes trying to start my old RD 500 look easy!

2. Forget about the gearbox. You ain't gonna start the beastie in Gear out on track.

3. Engine out of Gear. All we need to know is compression ratios to turn the engine. Then you gear up the starter to provide adequate turn speeds. It doesn't really matter what different componants are made out of as long as the starter motor can turn the engine.

However, it's all pretty hypothetical as nobody is going to stick a ruddy great starter motor off the back of a V8.

jjanicke

24th February 2009, 01:38

This all seems rather complicated for my liking.

1. Starting from cold. Forget it. As has been said, a F1 engine is siezed in cold mode and has Oil and all sorts pumped around to get it started. Makes trying to start my old RD 500 look easy!

2. Forget about the gearbox. You ain't gonna start the beastie in Gear out on track.

3. Engine out of Gear. All we need to know is compression ratios to turn the engine. Then you gear up the starter to provide adequate turn speeds. It doesn't really matter what different componants are made out of as long as the starter motor can turn the engine.

However, it's all pretty hypothetical as nobody is going to stick a ruddy great starter motor off the back of a V8.

Knock-on all good points but the last. That's what this thread is all about. They already have a motor to drive the wheels with energy regained under braking. This motor could double as the starter.

Just because an engine doesn't produce a lot of torque, there's no reason why it wouldn't take a lot to start. I'm sure the engines have a lot of compression to overcome.

Not following your logic. Let's say a motor produces X amount of torque and requires Y amount of torque to turn over and start. As Y approaches X the amount of torque left over = X-Y, which in this example approaches 0. There would be no torque left over to turn the gearbox and subsequently the wheels?

BTW Y is often referred to as parasitic loss. This loss of energy comes from friction, auxiliary drives (electricity, hydraulics, turbo's, super chargers, etc), and the drivetrain.

Knock-on

24th February 2009, 11:47

Knock-on all good points but the last. That's what this thread is all about. They already have a motor to drive the wheels with energy regained under braking. This motor could double as the starter.

I am not an electrical guru but as I understand it, you need different power delivery to start a motor than you would need to supliment power at speed.

Think of a battery. You get ones for short bursts such as a flash and more constant delivery units such as a radio.

I'm not sure a battery built for KERS would have sufficient "poke" coupled with a motor designed to turn the drive at high revs, to start an engine.

I'm also not sure why you would have a KERS fitted to the engine and not the transmission as there would be a loss of energy surely before drive to the track is achieved?

My last point surrounds the use of Battery itself. We know that Mein Furher favours mechanical KERS over battery so it may be a moot point for 2010.

ioan

24th February 2009, 16:27

I am not an electrical guru but as I understand it, you need different power delivery to start a motor than you would need to supliment power at speed.

80 HP should do for a 2.4 liter engine that is already at optimal temperature and lubrification parameters.

Knock-on

24th February 2009, 17:59

80 HP should do for a 2.4 liter engine that is already at optimal temperature and lubrification parameters.

And what do you base that on?

I have trouble understanding the corrolation between HP and Current that your comfortable with.

As I said, I am no expert in this field and cannot make the jump to light speed that you have come up with but the process as I understand it is as follows.

If we are talking about Electrical HP then you have about 750 Watts per HP and you can do some fancy calculations to work out Torque.

Once you work out the Torque, you can discover the multiple you need to transfer that Torque at a sufficient RPM to turn the engine enough to fire.

So, if you work out the power needed, then you can work out the rate of current (amperes) required.

Then you have to take into account initial inertia and compression of the engine so will have to have a higher peak and lastly to take into account where the power is fed into the drive of the car.

So, when you can answer some of the basics, we can start to understand whether the KERS system is suitable for starting the car.

ioan

24th February 2009, 21:16

And what do you base that on?

I have trouble understanding the corrolation between HP and Current that your comfortable with.

As I said, I am no expert in this field and cannot make the jump to light speed that you have come up with but the process as I understand it is as follows.

If we are talking about Electrical HP then you have about 750 Watts per HP and you can do some fancy calculations to work out Torque.

Once you work out the Torque, you can discover the multiple you need to transfer that Torque at a sufficient RPM to turn the engine enough to fire.

So, if you work out the power needed, then you can work out the rate of current (amperes) required.

Then you have to take into account initial inertia and compression of the engine so will have to have a higher peak and lastly to take into account where the power is fed into the drive of the car.

So, when you can answer some of the basics, we can start to understand whether the KERS system is suitable for starting the car.

:?:
You needn't calculate the intensity of current needed if you already know the output of the KERS unit, that is 60KW or roughly 80 HP.

F1 engines are high revving low torque engines, which means that you do not need impressively much torque in order to fire it up.

For now there is no info about how the combustion engine and the KERS engine are coupled so I can't say what it's rotation speed is so not way to know the torque it outputs towards the engine.

call_me_andrew

24th February 2009, 23:52

Not following your logic. Let's say a motor produces X amount of torque and requires Y amount of torque to turn over and start. As Y approaches X the amount of torque left over = X-Y, which in this example approaches 0. There would be no torque left over to turn the gearbox and subsequently the wheels?

BTW Y is often referred to as parasitic loss. This loss of energy comes from friction, auxiliary drives (electricity, hydraulics, turbo's, super chargers, etc), and the drivetrain.

You're forgetting that torque output changes with RPM.

ioan

25th February 2009, 01:04

Not following your logic. Let's say a motor produces X amount of torque and requires Y amount of torque to turn over and start. As Y approaches X the amount of torque left over = X-Y, which in this example approaches 0. There would be no torque left over to turn the gearbox and subsequently the wheels?

Why try to turn the gearbox and the whees using KESR when all you need is start the engine in Neutral and than use it to drive away?

jjanicke

25th February 2009, 01:44

I am not an electrical guru but as I understand it, you need different power delivery to start a motor than you would need to supliment power at speed.

Think of a battery. You get ones for short bursts such as a flash and more constant delivery units such as a radio.

I'm not sure a battery built for KERS would have sufficient "poke" coupled with a motor designed to turn the drive at high revs, to start an engine.

I'm also not sure why you would have a KERS fitted to the engine and not the transmission as there would be a loss of energy surely before drive to the track is achieved?

My last point surrounds the use of Battery itself. We know that Mein Furher favours mechanical KERS over battery so it may be a moot point for 2010.

An electric motor only has 2 states of "power delivery". It's either all the available torque, or none of it. That's the simple physics of an electrical motor.

I agree that the battery would become an issue, but only if all of it stored energy were exhausted. I believe that most KERS systems today use a capacitor style battery, meaning it builds up the juice under braking and then on demand delivers all of the stored up juice. So if the engine didn't start on the first try you would be done, because the KERS engine would have used up all of the juice.

The "poke" is actually the torque the electric KERS motor produces, which is also a variable of the power source. As we all know there's a lot of juice stored there. Remember the Williams mechanic that got shocked on an accidental discharge when the car pulled into the pits. I believe he had second or third degree burns. There's plenty of juice to start the engine.

And even with a mechanical system you could potentially re-start the engine. Go back to the days of old when you would crank start an engine. The same principle would apply here. And just like the energy issues with the capacitor you would have a limited window to re-start then engine. Use up all of the available stored kinetic energy and your done.

Now making any one of these ideas work in reality requires a lot more thought than just the available power of the KERS system to restart the engine.

You're forgetting that torque output changes with RPM.

I'm sorry but that's just incorrect. Torque is not relative to RPM. However HP is relative to RPM and Torque.

Actually electric motors product 100% instantly. Meaning the second the motor turns it's producing 100% of it available torque.

Why try to turn the gearbox and the whees using KESR when all you need is start the engine in Neutral and than use it to drive away?

You are correct. My point being that the V8 has enough torque to overcome the operational friction and parasitic loses AND power the drivetrain.

Were the KERS used to only start the engine it would have to be powerful enough to overcome the operational friction and parasitic loses and that's about it.

jjanicke

25th February 2009, 02:03

You're forgetting that torque output changes with RPM.

I believe I understand why you state that torque output changes with RPM. This holds true for an internal combustion engine, but not an electric engine. Your typical "reported" torque figures for an internal combustion engine is peak torque, whereas the reported torque figures of an electrical motor is across the entire operating range.

The "torque" curve of a internal combustion engine isn't actually a variable of RPM but the physics of combustion. For example look at the torque curve characteristics of a diesel engine and that of a gasoline engine. Very different. This is because of the behavior of combustion of the fuel in question.

ioan

25th February 2009, 10:34

You are correct. My point being that the V8 has enough torque to overcome the operational friction and parasitic loses AND power the drivetrain.

My bad, I misunderstood your post. Thanks for explaining it.

Knock-on

25th February 2009, 12:45

Why try to turn the gearbox and the whees using KESR when all you need is start the engine in Neutral and than use it to drive away?

Well, as we're at the guessing stage, I would suggest it was logical to recover energy from the KERS as close to output drive and as far away from the pistons as possible.

Logically, 99.999% of the time, KERS would be for adding drive and not starting the engine so they would want it to lose the least amount of power as possible in delivering drive.

Ergo, to restart the engine, it would have to be in gear in order to turn the pistons.

Knock-on

25th February 2009, 12:48

An electric motor only has 2 states of "power delivery". It's either all the available torque, or none of it. That's the simple physics of an electrical motor.

I agree that the battery would become an issue, but only if all of it stored energy were exhausted. I believe that most KERS systems today use a capacitor style battery, meaning it builds up the juice under braking and then on demand delivers all of the stored up juice. So if the engine didn't start on the first try you would be done, because the KERS engine would have used up all of the juice.

The "poke" is actually the torque the electric KERS motor produces, which is also a variable of the power source. As we all know there's a lot of juice stored there. Remember the Williams mechanic that got shocked on an accidental discharge when the car pulled into the pits. I believe he had second or third degree burns. There's plenty of juice to start the engine.

And even with a mechanical system you could potentially re-start the engine. Go back to the days of old when you would crank start an engine. The same principle would apply here. And just like the energy issues with the capacitor you would have a limited window to re-start then engine. Use up all of the available stored kinetic energy and your done.

Now making any one of these ideas work in reality requires a lot more thought than just the available power of the KERS system to restart the engine.

I'm sorry but that's just incorrect. Torque is not relative to RPM. However HP is relative to RPM and Torque.

Actually electric motors product 100% instantly. Meaning the second the motor turns it's producing 100% of it available torque.

You are correct. My point being that the V8 has enough torque to overcome the operational friction and parasitic loses AND power the drivetrain.

Were the KERS used to only start the engine it would have to be powerful enough to overcome the operational friction and parasitic loses and that's about it.

Thanks, good explanation.

With the last paragraph, and if my previous post makes sense, it would be unlikely that KERS would indeed be feasible for starting a car.

ioan

25th February 2009, 13:41

Well, as we're at the guessing stage, I would suggest it was logical to recover energy from the KERS as close to output drive and as far away from the pistons as possible.

Logically, 99.999% of the time, KERS would be for adding drive and not starting the engine so they would want it to lose the least amount of power as possible in delivering drive.

Ergo, to restart the engine, it would have to be in gear in order to turn the pistons.

As far as I know, at least in Ferrari's case, the KERS is situated in the front of the engine under the fuel tank and thus it should transmit power directly through the engine.

Knock-on

25th February 2009, 14:05

As far as I know, at least in Ferrari's case, the KERS is situated in the front of the engine under the fuel tank and thus it should transmit power directly through the engine.

That would mean adding energy directly at the crank :confused:

Any link as it doesn't make sense to me?

ioan

25th February 2009, 15:56

That would mean adding energy directly at the crank :confused:

Any link as it doesn't make sense to me?

Here:

The KERS on the F60 was designed by Ferrari in collaboration with Magneti Marelli and is centrally mounted on the engine under the rear part of the chassis...
http://www.f1technical.net/news/11382

Knock-on

25th February 2009, 17:48

Here:

http://www.f1technical.net/news/11382

This link is interesting.

http://lightbulbs.org/ferrari-tested-at-least-three-different-kers-configurations-in-f1-car

Is the position they are talking about in the F1 Tech article the mounting of the battery I wonder?

Also, they mention that it's centrally mounted (logically) under the rear of the Chassis. Knowing how Journo's often fail to differentiate between engine and transmission, does this sound to you more like it's mounted behind the engine? If they were going to mount the power input directly into the emgine, I would have thought the ideal mount would be infront of the crank behind the driver under the fuel tank?

Bagwan

25th February 2009, 18:05

Does it actually matter whether the power goes through the transmission or directly to the wheels ?
We know they are getting power from the deceleration of the car , to charge the batteries on-board .
Close to the same amount of energy needed to slow one of those cars , and , even though they are light , that's significant , is stored

If the amount of power is significant enough to effect the racing , it seems like it should be enough to get the thing going from a stop .

It is admittedly a stretch , but might be worth mentioning , that none of the General Motors EV-1s ever required a brake job . Such is the power of momentum .
It's another element of change added to the mix , as brakes will last longer with the KERS in tandem .

ioan

25th February 2009, 18:24

Is the position they are talking about in the F1 Tech article the mounting of the battery I wonder?

It's the mounting of KERS, so I assume it's the electric motor + the batteries.
Remember those small air intakes that are situated under the main air intakes? Those are used for cooling KERS.

Also, they mention that it's centrally mounted (logically) under the rear of the Chassis. Knowing how Journo's often fail to differentiate between engine and transmission, does this sound to you more like it's mounted behind the engine? If they were going to mount the power input directly into the emgine, I would have thought the ideal mount would be infront of the crank behind the driver under the fuel tank?

I think it's actually the Ferrari press release not what some journo dreamed up, so I suppose they meant engine.

Now, given that is mounted on the engine and under the rear part of the chassis (which as far as I know ends behind the tub in which sits the driver), that it is in fact mounted on the front side of the engine under the fuel tank.
Mounting it there, very close to the CoG means that it will not affect to much the balance of the car even if they decide not to run in it during the season.

IMO, having it coupled directly to the engine's crank shaft simplifies things in the transmission compartment as they don't have to design a completely different gearbox that would have an entry from the engine and one from KERS.

Anyway the biggest troubles are with providing sufficient cooling for it and anything that would be behind the engine would be difficult to cool down as there is no more cold air available at that point, not to mention the very tightly packaged rear of the Ferrari.

jjanicke

25th February 2009, 18:34

As far as I know, at least in Ferrari's case, the KERS is situated in the front of the engine under the fuel tank and thus it should transmit power directly through the engine.

That could just be the location of the battery and engine for weight/balance purpose. How the KERS ties into the drivetrain/engine is what we would need to know. As Knock-On points out you would want the KERS system tied as close to the intended source/target as possible to avoid parasitic losses. Which leads me to believe the system engages at the drive-shaft/wheel, and after the gearbox.

ioan

25th February 2009, 18:54

That could just be the location of the battery and engine for weight/balance purpose. How the KERS ties into the drivetrain/engine is what we would need to know. As Knock-On points out you would want the KERS system tied as close to the intended source/target as possible to avoid parasitic losses. Which leads me to believe the system engages at the drive-shaft/wheel, and after the gearbox.

That's something very complicated and prone to failures.
I suppose we'll get some info about it during the season though.

Knock-on

26th February 2009, 11:33

That's something very complicated and prone to failures.
I suppose we'll get some info about it during the season though.

Really?

I would have thought that running additional power into the tranny would be inherently easier than drilling a bloody great hole in the bottom of the crank and trying to balance the power generated from the engine with recovered energy input into the crank.

In fact, although I have no evidence to support my opinion apart from common sense, I would have said it would be horrendously complicated and fraught with never concieved problems to attempt this.

Forget about loss of energy etc, it just makes no sense whatsoever whereas the gearbox is designed to transmit power to drive and is ideally suited to accept the additional power from the KERS.

I'm sorry ioan. I know you say you like F1 for the technical aspect rather than the spectacle but mounting the kers on the front of the engine makes as much technical sense as making pistons out of chocolate.

ioan

26th February 2009, 12:33

I'm sorry ioan. I know you say you like F1 for the technical aspect rather than the spectacle but mounting the kers on the front of the engine makes as much technical sense as making pistons out of chocolate.

At your request, I provided you with a link from the Ferrari press release that states that the KERS in mounted on the front of the engine.
Till you provide a link saying otherwise I'll stick to my guns!

Cheers! :)

Knock-on

26th February 2009, 13:05

At your request, I provided you with a link from the Ferrari press release that states that the KERS in mounted on the front of the engine.
Till you provide a link saying otherwise I'll stick to my guns!

Cheers! :)

Sorry, I must have missed that link and looking back, can't seem to find it.

Can you repost it please.

ioan

26th February 2009, 17:45

http://forums.motorsport.com/forums/showpost.php?p=594218&postcount=61

:rolleyes:

Knock-on

26th February 2009, 18:16

http://forums.motorsport.com/forums/showpost.php?p=594218&postcount=61

:rolleyes:

At your request, I provided you with a link from the Ferrari press release that states that the KERS in mounted on the front of the engine.
Till you provide a link saying otherwise I'll stick to my guns!

Cheers! :)

Sorry ioan, that is an article from F1 Technical which is a commercial site a bit like motorsport.com

It appears that a lot of the article may have been lifted from a Ferrari press release but is not credited with it.

Have you got the genuine press release?

Also, it says the KERS is mounted on the engine at the back of the chassis. Have you a link or exploded diagram of the chassis for reference?

It could well be mounted on a central line at the back of the engine feeding into the transmission via the connecting rod from engine to tranny. This is the earliest they would put it in my opinion and if feeding into the tranny not the engine.

ioan

26th February 2009, 20:42

Sorry ioan, that is an article from F1 Technical which is a commercial site a bit like motorsport.com

It appears that a lot of the article may have been lifted from a Ferrari press release but is not credited with it.

Given that several sites published exactly the same text it is clearly the official Ferrari press release. Not being a Ferrari accredited journo I haven't received the original press release.

Other sources:
http://www.motorsport.com/news/article.asp?ID=316524&FS=F1
http://www.pitpass.com/fes_php/pitpass_news_item.php?fes_art_id=36816

Also, it says the KERS is mounted on the engine at the back of the chassis. Have you a link or exploded diagram of the chassis for reference?

It could well be mounted on a central line at the back of the engine feeding into the transmission via the connecting rod from engine to tranny. This is the earliest they would put it in my opinion and if feeding into the tranny not the engine.

This part of your post makes it obvious that you do not know what an F1 chassis is all about, and you are only trolling.

I refuse to lose my time continuing to debate with someone that doesn't have the slightest clue about what an F1 chassis looks like.

FYI:
http://www.f1technical.net/articles/63

PS: I'm sorry, for the other people who read this thread and maybe found it interesting until now, that you felt the need to drag it into the mud of your ignorance because of your need for a fight.

Knock-on

27th February 2009, 10:51

Given that several sites published exactly the same text it is clearly the official Ferrari press release. Not being a Ferrari accredited journo I haven't received the original press release.

Other sources:
http://www.motorsport.com/news/article.asp?ID=316524&FS=F1
http://www.pitpass.com/fes_php/pitpass_news_item.php?fes_art_id=36816

Thank you. The Motorsport article credits the piece to Ferrari which is what I asked for. Isn't it easy when you actually use facts that can be quantified ;)

This part of your post makes it obvious that you do not know what an F1 chassis is all about, and you are only trolling.

I refuse to lose my time continuing to debate with someone that doesn't have the slightest clue about what an F1 chassis looks like.

FYI:
http://www.f1technical.net/articles/63

PS: I'm sorry, for the other people who read this thread and maybe found it interesting until now, that you felt the need to drag it into the mud of your ignorance because of your need for a fight.[/QUOTE]

ioan. There is no reason at all to be rude.

Because I cannot understand why they would mount the KERS at the front of the engine as you claim, doesn't give you licence to carry on like a child.

The Chassis in F1 cars use the engine as a stressed member which bolts onto the rear. We all know this. It isn't rocket science and there is no reason to go around calling people ignorant who obviously appreciate this fact.

The press release is suitably vague to not give away exactly what they are doing with it as you would expect.

For example, the nose section of the Ferrari is positioned in front of the gearbox is it not? Factually correct and as vague as possible.

All I am saying is that there are a lot of assumptions we are both making because there are no facts.

But you are right in one matter. This has descended into a discussion to your usual personal insults and as such, I am not going to contribute unless more information comes availiable.

:wave:

ioan

27th February 2009, 11:23

Thank you. The Motorsport article credits the piece to Ferrari which is what I asked for. Isn't it easy when you actually use facts that can be quantified ;)

I'm glad you accepted the facts with 3 links to support them, I was already thinking you'll ask for the original PDF document issued by Ferrari.

FYI:
http://www.f1technical.net/articles/63

PS: I'm sorry, for the other people who read this thread and maybe found it interesting until now, that you felt the need to drag it into the mud of your ignorance because of your need for a fight.

ioan. There is no reason at all to be rude.

I wasn't being any more rude that you when you asked me for the same link twice on the same page of the thread!

Because I cannot understand why they would mount the KERS at the front of the engine as you claim, doesn't give you licence to carry on like a child.

It isn't me claiming that, it's in their press release.

The Chassis in F1 cars use the engine as a stressed member which bolts onto the rear. We all know this. It isn't rocket science and there is no reason to go around calling people ignorant who obviously appreciate this fact.

The engine is a stressed part of the F1 car, but the Chassis and the engine are 2 different structural parts and accordingly have different names.

The press release is suitably vague to not give away exactly what they are doing with it as you would expect.

The press release is pretty exact if you look at it trying to make use of the info and not trying to prove that it's wrong.

Centrally mounted on the engine under the back side of the chassis points to a very specific location.

For example, the nose section of the Ferrari is positioned in front of the gearbox is it not? Factually correct and as vague as possible.

You love to ridicule everything that doesn't suit your POV even when there are proves that you are not in the right, and this is extremely childish.

All I am saying is that there are a lot of assumptions we are both making because there are no facts.

Yes there are facts, it's all written black on white in Ferrari's press release.
You don't want to accept that you were wrong? Well that's a huge problem you have always had and I believe you'll keep it forever, cause you can't surpass that level.

But you are right in one matter. This has descended into a discussion to your usual personal insults and as such, I am not going to contribute unless more information comes availiable.

You say what you like, but you started the mudslinging while I was more than happy to provide plenty of data to support a serious technical debate that was looking interesting and many people did take part in it.

PS: Please do attribute the quotes the right way next time.