Environmental Engineering Reference
In-Depth Information
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
200
T
e
70
P
eng
60
150
215
22
230
210
50
250
100
40
270
30
300
50
400
20
700
BSFC
0
10
1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000
Engine speed (rpm)
Figure 1.29 Endura 1.8 L CIDI engine fuel map
indirect effect such as transmission gear selection. Transmission gear selection, or
powertrain matching, will impact fuel economy over a particular drive cycle due to
the location of the engine and driveline operating points over the drive cycle.
Table 1.14 Factors impacting fuel economy
FE contributor
Ranking (low, medium, high)
Vehicle rolling resistance/suspension geometry
M
Vehicle cross-sectional area
H
Vehicle weight
H
Transmission control strategy
M
Gear steps and gear shift ratio coverage
H
Transmission efficiency
H
Engine efficiency
H
Engine thermal management
M
Engine and ancillary inertias
L
Wheel and driveline inertias
L
Tyre rolling resistance
L
Power for ancillaries
M
The basic conversion between fuel economy and fuel consumption is given in
(1.31) according to Reference 16:
235
:
21
x
ð
L
=
100 km
Þ
mpg
ð
US
Þ¼
ð
1
:
31
Þ
21
x
ð
L
=
100 km
Þ
282
:
mpg
ð
UK
Þ¼
