sanredrose wrote:Can some explain what is KERS system ? Why some teams are opposed against bringing it in ??
This is a special solution using mechanical flywheel techonolgy developed by three companies:
“The mechanical KERS system utilises flywheel technology developed by Flybrid Systems to recover and store a moving vehicle’s kinetic energy which is otherwise wasted when the vehicle is decelerated. The energy is received from the driveline through the Torotrak CVT, engineered and supplied by Xtrac, as the vehicle decelerates, and is subsequently released back into the driveline, again through the CVT, as the vehicle accelerates. The FIA has defined the amount of energy recovery for the 2009 season as 400kJ per lap giving the driver an extra 80hp over a period of 6.67 seconds.
“Compared to the alternative of electrical-battery systems, the mechanical KERS system provides a significantly more compact, efficient, lighter and environmentally-friendly solution.
“The components within each variator include an input disc and an opposing output disc. Each disc is formed so that the gap created between the discs is ‘doughnut’ shaped; that is, the toroidal surfaces on each disc form the toroidal cavity.
“Two or three rollers are located inside each toroidal cavity and are positioned so that the outer edge of each roller is in contact with the toroidal surfaces of the input disc and output disc.
“As the input disc rotates, power is transferred via the rollers to the output disc, which rotates in the opposite direction to the input disc.
“The angle of the roller determines the ratio of the Variator and therefore a change in the angle of the roller results in a change in the ratio. So, with the roller at a small radius (near the centre) on the input disc and at a large radius (near the edge) on the output disc the Variator produces a ‘low’ ratio. Moving the roller across the discs to a large radius at the input disc and corresponding low radius at the output produces the ‘high’ ratio and provides the full ratio sweep in a smooth, continuous manner.
“The transfer of power through the contacting surfaces of the discs and rollers takes place via a microscopic film of specially developed long-molecule traction fluid. This fluid separates the rolling surfaces of the discs and rollers at their contact points.
“The input and output discs are clamped together within each variator unit. The traction fluid in the contact points between the discs and rollers become highly viscous under this clamping pressure, increasing its ’stickiness’ and creating an efficient mechanism for transferring power between the rotating discs and rollers.”
sanredrose wrote:Why some teams are opposed against bringing it in ??
Some road cars already use this technology so BMW and Honda can maximize the advantage of KERS system. I don't think it's a safety or cost issue as opposing teams claim. It is the performance gain they fear about.
You can also read this article from Wikipedia:
Max Mosley of the FIA has announced that all cars will become hybrid by 2013, along with other changes to the vehicles. The governing body of international motor sport, the FIA, has allowed the use of 60 kW "Kinetic Energy Recovery Systems" (KERS), in the regulations for the 2009 Formula One season. BMW and Honda are testing it.
The hybrid system that will be implemented in Formula 1 is known as KERS, which stands for Kinetic Energy Recovery System. The maximum power that can be released from such a system is restricted to 60 kW by the FIA. Energy can either be stored as mechanical energy (as in a flywheel) or can be stored as electrical energy (as in a battery or supercapacitor).
The first of these systems to be revealed was the Flybrid which appeared in an article in Racecar Engineering magazine.
The Flybrid F1 KERS System weighs 24 kg and has an energy capacity of 400 kJ after allowing for internal losses. A maximum power boost of 60 kW (81.6 PS) for 6.67 sec is available. The 20-cm diameter flywheel weighs 5.0 kg and revolves at up to 64,500 rpm. Maximum torque is 18 nm. The system occupies a volume of 13 liters.
Two minor incidents involved testing the KERS system in 2008 have been reported. The first occurred when the Red Bull Racing team tested their KERS battery for the first time in July, it malfunctioned and caused a fire scare, resulting in the team's factory being evacuated. The second was less than a week later when a BMW Sauber mechanic was given an electric shock when he touched Christian Klien's KERS-equipped car during a test at the Jerez circuit.
Automobile Club de l'Ouest, the organizer behind the annual 24 Hours of Le Mans event and the Le Mans Series is currently "studying specific rules for LMP1 which will be equipped with a kinetic energy recovery system."
Toyota has used a supercapacitor for regeneration on Supra HV-R hybrid race car that won the 24 Hours of Tokachi race in July 2007.
Some useful links about KERS:
1. Kinetic energy storage by a flywheel --> Lecture Notes
2. From FIA 2009 Sporting Regulations:
- 5.2.1 The use of any device, other than the 2.4 litre, four stroke engine described in 5.1 above and one KERS, to power the car, is not permitted.
5.2.2 With the exception of one fully charged KERS, the total amount of recoverable energy stored on the car must not exceed 300kJ. Any which may be recovered at a rate greater than 2kW must not exceed 20kJ.
5.2.3 The maximum power, in or out, of any KERS must not exceed 60kW.
Energy released from the KERS may not exceed 400kJ in any one lap.
Measurements will be taken at the connection to the rear wheel drivetrain.
5.2.4 The amount of stored energy in any KERS may not be increased whilst the car is stationary during a race pit stop.
Release of power from any such system must remain under the complete control of the driver at all times the car is on the track.
9.9.1 The KERS must connect at any point in the rear wheel drivetrain before the differential. If connected between the differential and wheel the torque applied by the KERS to each wheel must be the same.