appendix a - Velocidade

CONTENTS
4
The effect of speed on noise, vibration and emissions
from vehicles
May 1998
1 INTRODUCTION..............................................................................................................7
1.1 The cases to be considered ...........................................................................................7
1.2 Overview......................................................................................................................8
2 EMISSIONS .......................................................................................................................9
2.1 Vehicle emission production processes .........................................................................9
2.1.1 Overview of the production of exhaust gases ......................................................9
2.1.2 Catalytic converters ..........................................................................................12
2.1.3 Other emissions ................................................................................................12
2.1.4 Health impacts of emissions ..............................................................................12
2.2 The effects of speed and driving mode on emissions....................................................13
2.3 Environmental effects of speed control strategies........................................................18
2.3.1 Urban traffic calming ........................................................................................18
2.3.2 Inter-urban traffic calming ................................................................................21
2.4 Emission models.........................................................................................................22
2.5 Emissions databases ...................................................................................................22
2.6 Conclusions................................................................................................................23
3 NOISE EMISSION ...........................................................................................................25
3.1 Introduction ...............................................................................................................25
3.2 Noise perception and measurement.............................................................................25
3.3 Sources of road traffic noise .......................................................................................27
3.4 The effect of speed on sources of vehicle noise...........................................................29
3.5 Road traffic noise prediction models...........................................................................31
3.6 Choice of noise measure - equivalent or maximum noise levels?..................................33
3.7 Effects of acceleration and deceleration ......................................................................35
3.8 Effects of speed management devices .........................................................................35
3.9 Tempo 30...................................................................................................................35
3.10 Effects of gradients on the noise-vs-speed relation ....................................................36
3.11 Road surface effects .................................................................................................36
3.12 Distance effects ........................................................................................................37
4 VIBRATION.....................................................................................................................39
5 HOW THE MODELS FIT WITHIN THE MASTER FRAMEWORK...............................41
6 CONCLUSIONS...............................................................................................................42
ACKNOWLEDGEMENTS ..................................................................................................44
7 REFERENCES.................................................................................................................45