# Can anyone explain kers in formula one cars?

1. Aug 26, 2009

### brandy

can anyone explain kers in formula one cars?
like how it works on a mechanical level.
and the difference between flywheel and electrical kers.

2. Aug 26, 2009

### xxChrisxx

There is an electric motor attached to the gearbox, under braking the gearbox isnt being used to drive the wheels its being used to drive the motor as a generator.

In electrical systems this makes electricity stored in a battery/supercapacitor.
In flywheel systems it spins up a flywheel.

When they press the KERS boost button, this stored energy spins the electric motor attached to the hearbox to provide the extra power.

The exact specifics are abviously a closely gaurded secret, but this is basically how it works.

3. Aug 26, 2009

### TheDestroyer

"A kinetic energy recovery system (KERS) is "a system that is designed to recover kinetic energy from the car during braking, store that energy and make it available to propel the car". Such a system is basically an efficient CVT gearbox joined to a flywheel that rotates when the cars undergo braking. Such systems are being developed for Formula One and they have been included in the FIA regulations in December 2006."

This was from Wikipedia, and the concept is very simple, it uses the conservation of angular momentum, since for a rotating wheel you have the energy:

E=1/2 I w^2

where E is the kinetic rotational energy, I is the moment of inertia, w is the angular momentum.

With this, you can upon breaking star rotating such a frictionless wheel and save the energy, and then restore it back ;)

Does this answer satisfy you? if not, ask more specifically so we can think of a better answer :)

Good luck :)

4. Aug 27, 2009

### brandy

so the wheel is spinning, in electric kers when braking the wheel has to spin the generator which is a retarding force because it is working against the magnetic fields, and thats how it stores energy.
is that right?

with mechanical kers i get even more confused,
when braking the kers cant aid the braking can it?
the wheel is spinning slower how does this make the flywheel spin faster?
and when the energy is released, is the wheel just connected to the flywheel through a CVT where the ratio of the flywheel-speed to the wheel-speed is; low:high, and the wheel spins cause the flywheel is spinning???

5. Aug 27, 2009

### xxChrisxx

The Williams KERS flywheel is just a storage device, it's still hooked up to an electric motor/generator connected to the gearbox.

With the flywheel system the generator spins the flywheel up to 100K RPM.

The specific details are sketch because its such a closely guarded secret.

You've got to remember in both systems en electric motor is the thing that is doing all the work. It's just the storage systems that are different.

6. Aug 27, 2009

### brandy

oooh ok.
so how does the flywheel connect to the motor?
and iv been looking on the web and u can get answers for this kind of stuff its just im too dumb to understand them :P

7. Aug 27, 2009

### xxChrisxx

Well thats the question isnt it...

I cant find a jot of specific information about how its all connected together.