Fuel System and Fuel Measurement - Decreasing Fuel Consumption and Exhaust Gas Emissions in Transportation - page 62

urban extra urban

-1
[8.2 l*(100 km) ]

-1
[5.1 l*(100 km) ]

part one

200 20

hight street cycle

basic city cycle

160 16

120 12

6.

5. 5.

80 10

4.

4.

3. 3.

40 4

2.

2. 2.

1.

1. 1.

0 0

0 200 400 600 800 1000

time [s]

fuel consumption
speed

Fig. 4.3 Fuel consumption of an average European car relative to time of NEDC

4.1.1.2 Heavy-Duty Vehicle Technology

Since trucks and buses are too heavy and too large, not the entire vehicle's but the
engine's emissions are controlled at an engine test bench with computer-supported
driving cycle programs [ 16 ].
In Europe, the emissions of heavy-duty vehicles are examined using Directive
70/220/EEC including amendments and corrections. The European Stationary
Cycle ESC is a steady-state procedure with a 13-point examination. The European
Load Response Cycle ELR has the purpose of opacity determination. In the
European Transient Cycle ETC, different driving conditions are represented by
three parts, including urban (maximum speed is 50 km h -1 (31.05 mi h -1 ), with
frequent starts, stops and idlings), rural (step acceleration segment, average speed
is 72 km h -1 ) (44.7 mi h -1 ), and motorway driving (average speed is 88 km h -1 )
(54.65 mi h -1 ). The duration of the entire cycle is 1,800 s. Each part lasts for
600 s [ 17 ].
However, with specific and large test dynamometers, which sometimes have
artificial cooling, pressurization, and air humidification, heavy duty trucks and
buses can be dynamically controlled for research and development experiments;
see Fig. 4.4 [ 18 ].
In the USA, the EPA Urban Dynamometer Driving Schedule (UDDS or Cycle D)
has been developed for chassis dynamometer testing of heavy-duty vehicles. The