Technical University of Gdansk, Poland
Transcript of Technical University of Gdansk, Poland
Technical University of 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
01.0
3.0
3800
200
r
ef
mr
NL
NW
WL
Ff
ReRr
LRF
LWR
m
yr
r
y
0)sin(
0)cos(
a
a
0101.0"20
0110.0'04
0187.0'30
0100.0'00
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
WL
Ff
amI
IRF
LWR
m
r
y
0
0
01.0
28*4.1
20
3.0
3800
200
r
ef
kgmm
kgm
mr
NL
NW
I
0107.0/1.0
0100.0/0.0
2
2
m
m
fsma
fsma
Errors in Rolling Resistance Estimations
(air drag)
Ry
Rr
W
L F
r
e
A
V
01.0
20
200
3.0
3800
200
r
ef
kgm
mmB
mr
NL
NW
WL
Ff
vrBcA
ARF
LWR
m
x
r
y
22
0
0
2
0172.0/20
0100.0/0
m
m
fsma
fsmv
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