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Frictional loss distribution in passenger cars
Peter Andersson
VTT Technical Research Centre of Finland
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Background
“Global energy consumption due to friction in passenger cars”
by
Kenneth Holmberg*, Peter Andersson*, and Ali Erdemir#
*VTT Technical Research Centre of Finland
#Argonne National Laboratory, USA
Paper submitted to Tribology International on the 4th November 2011
Literature study (111 Refs.)
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- 612 million passenger cars are in use today worldwide
- One third of the car fuel energy goes to overcome friction
- The average annual passenger car mileage is 12 130 km
=> 340 l and 510 € used to overcome friction / car & year
- New technology can reduce friction with 10-80%
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Passenger Car Energy Balance
EXHAUST
33%
FUEL
ENERGY
Thermal
energy
losses
Total
energy
losses
COOLING
29%
100%
MECHANICAL
LOSSES
38%
(INDICATED
POWER)
FRICTION
LOSSES
33%
AIR DRAG 5%
ENGINE FRICT.
11.5%
TRANSM. 5%
ROLLING
RESIST. 11.5%
BRAKES 5%
AIR DRAG 5%
ENERGY
TO MOVE
THE CAR
21.5%
14 kW
Brake
Power
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GREAT POTENTIAL TO SAVE ENERGY BY NEW
TECHNOLOGY IN CARS AND MACHINERY
NEW SOLUTIONS FOR FRICTION REDUCTION
• Advanced coating structures: DLC, TS, nano-composites etc.;
10-50% friction reduction in lubricated contacts.
• New surface texturing methods: laser surface texturing;
25-50% friction reduction; 4% engine fuel reduction.
• New boundary lubrication additives and fluids: glycerol mono-oleate
in PAO vs DLC; nanomaterials as additives like WS2, MoS2 and H3BO3
• Low viscosity fluids
• Ionic liquids: 25-50% friction reduction.
• Biomimetics: biomolecular protein additives, brushes of charged
polyelectrolytes, porcine gastric mucin, glycoprotein mucin.
• Low friction tyre design: high pressure, low-friction design etc.
OIL CONSUMPTION AND POTENTIAL FRICTION SAVINGS IN PASSENGER CARS GLOBALLY
Gas and diesel oil used in passenger cars today
Energy used today to overcome friction in cars
Potential oil fuel savings
Potential CO2 savings
Potential economic savings
Short term (5-10 year):
117 000 million liters/a
210 million tonnes/a
174 000 million €/a
631 000 million liters/a
7.3 million TJ/a
Long term (15-25 year):
385 000 million liters/a
700 million tonnes/a
576 000 million €/a