Rolling Resistance Influence on Fuel Consumption Decrease of tires - - PowerPoint PPT Presentation

Technical University

• f Gdansk, Poland

Rolling Resistance Influence on Fuel Consumption

[Silka W.: Energochłonność ruchu samochodu, Warszawa, WKŁ 1997]

Decrease of tires Rolling Resistance by 10% results in approximately 3% reduction of fuel consumption

Number of vehicles in Poland - 15 000 000, in USA – 250 000 000 Use of tires with 10% less Rolling Resistance would reduce daily fuel consumption by approximately 1000 tons (USA - 35 000 tons) Daily savings in CO2 emission would amount to 3000 tons (USA – 100 000 tons)

Resistance forces acting on typical passenger car

[Silka W.: Energochłonność ruchu samochodu, Warszawa, WKŁ 1997]

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% ECE cycle 90 km/h 120 km/h

Air drag Rolling resistance Inertia forces

Rolling Resistance

Rolling Resistance

Rolling Resistance

Road Methods of Rolling Resistance Evaluation Towing (car or trailer) Coast-down Torque measurements Fuel consumption

Laboratory Methods of Rolling Resistance Evaluation Measurement of:

* Spindle force * Torque of the power system * Coast-down time

Laboratory Methods of Rolling Resistance Evaluation

Errors in Rolling Resistance Estimations (misalignments / grade)

a

Ry Rr W L F r e

01 . 3 . 3800 200      r e f m r N L N W W L F f R e R r L R F L W R

m y r r y

             ) sin( ) cos( a a

0101 . " 20 0110 . ' 04 0187 . ' 30 0100 . ' 00            

m m m m

f f f f a a a a

Errors in Rolling Resistance Estimations (acceleration)

a

Ry Rr W L F r e I

W L F f a m I I R F L W R

m r y

         

01 . 28 * 4 . 1 20 3 . 3800 200         r e f kg m m kg m m r N L N W

I

0107 . / 1 . 0100 . / .

2 2

     

m m

f s m a f s m a

Errors in Rolling Resistance Estimations (air drag)

Ry Rr W L F r e A V

01 . 20 200 3 . 3800 200        r e f kg m mm B m r N L N W W L F f v r B c A A R F L W R

m x r y

             2 2

2



0172 . / 20 0100 . /      

m m

f s m a f s m v

Errors in Rolling Resistance Estimations (acceleration)

Generally, equipment constructed for Traction measurements is not appropriate for Rolling Resistance measurements as the Traction and Rolling Resistance forces are of different magnitude. Usually Rolling Resistance force is at about 100 times less than maximal possible Traction force.

Belgian Trailer for Rolling Resistance Measurements

Principle of Operation

ft = Wt/Z Pf Z 

Ciężar Kierunek jazdy

Wt 

7 4 3 2 6 1 5 8 9

LOAD

1-frame; 2-loading system; 3-axis of frame and loading device; 4-measuring arm; 5-test wheel; 6-adjustable load; 7-damper and spring

Polish Trailer Mk.1

Polish Trailer Mk.1

rama przyczepy wahacz pomiarowy

FRAME ARM

Polish Trailer Mk.2

Polish trailer Mk. 3

Calibration

5 3 4 2 1 6 7 9 8 l x a

B

C

A’ A C

α θ P b Wt

Examples of the results

Nawierzchnia odcinka pomiarowego P1 S5 P2 S3 S2 S1 S4 Wartość współczynnika

0,0106 0,0116 0,0117 0,0118 0,0135 0,0140 0,0159

Test section RR coefficient