HARMONOISE -IMAGINE road source model

A short overview for GRB September 2008

Erik de Graaff M+P consulting engineers

Informal document No. GRB-48-6(48th GRB, 1-3 September 2008,agenda item 7)

Transmitted by the expert from the Netherlands

No.No.22/17/17

EC Environmental noise directive 2002/49/EC• Requests noise maps and action plans for

- Agglomerations (populations > 100 000) - Major roads- Major railways- Major civil airports

• Ready in 2008

• Recommended calculation methods- Roads: NMPB-96 (the French method) - Railways: RLM2 (the Dutch method) - Airports: ECAC 29 - Industrial sites: ISO 9613

• Future calculation method: EU harmonised

No.No.33/17/17

EU research projects on harmonized methods

• Harmonoise (FP5 2001-2004)• Imagine (FP6 2004-2007)• 15 project partners from all over europe (D, F,

I, NL, PL, S, UK• 4 source models (road, rail, air, industry)• 1 propagation model• Validation with measurements

No.No.44/17/17

Harmonoise - IMAGINE traffic noise model

• Prediction of the noise emission of the average European road vehicle, based on:- vehicle class- vehicle speed

• With optional calculations for:- vehicle acceleration/deceleration- road surface type, age, gradient, meteo- directivity- regional variations

No.No.55/17/17

Model structure

• Separate calculation of rolling and propulsionnoise:- Rolling noise:

- Propulsion noise:

• Coefficients A, B and C are known for each vehicle class, per 1/3-octave frequency band

)log()()( refRRWR vvfBfAL ⋅+=

aCv

vvfBfAL P

ref

refPPWP .)()( +

−⋅+=

No.No.66/17/17

Vehicle classes

category name description vehicle category in EU/ECE type

approval

1 Light motor vehicles Passenger cars, delivery vans

? 3.5 tons, SUV’s, MPV’s including trailers and caravans

M1 and N1

2 Medium heavy vehicles

Medium heavy vehicles, delivery vans > 3.5 tons, buses, touring

cars, etc. with two axles and twin tyre mounting on rear axle

M2, M3 and N2, N3

3 Heavy vehicles Heavy duty vehicles, touring cars, buses, with three or more axles

M2- and N2 with trailer, M3 and N3

4a mopeds, tricycles or quads with ? 50 cc L1, L2, L6

4 Powered two-wheelers 4b motorcycles, tricycles or

quads with > 50 cc L3, L4, L5, L7

No.No.77/17/17

Source geometry

• Two source heights:- Rolling noise : 80% to lower and 20% to higher source- Propulsion noise: 20% to lower and 80% to higher source- Motor cycle : no rolling noise, 100% to single source

source at 30 cm

No.No.88/17/17

Corrections factors (1)

• Regional variations- engine type (only cat 1) (Otto, Diesel)- tyre width (only cat 1) through its relation with

weight- tyre mounting (summer, winter, studded)- age (only cat 1)- fraction of IRESS (illegal replacement exhaust

silencing systems) (all categories)- fraction of VANs in cat 1. - distinction between three and multi-axle HDV’s.

No.No.99/17/17

Corrections factors (2)

• Meteo conditions- Temperature- Road surface wetness

• Type of road surface- Acoustic classification scheme developed in EU 6th

framework project SILVIA fits in this calculation scheme,

Reference condition DAC/SMA 0-11Effect of other surface defined for passenger cars and trucksFrequency dependence and speed dependence formulated

No.No.1010/17/17

Examples of data acquisition program, trucks

Volvo truck test chamber

TRL pull away test

M+P road side testing

No.No.1111/17/17

Examples of data acquisition program cars

TUG and M+P pass-by testing

PolandM+P pass-by testing Italy

M+P accelerated pass-by testing

TUG controlled single vehicle

testing

TRL pass-by testing UK,

SP pass-by testing Sweden

No.No.1212/17/17

Examples data acquisition program motorcycles

M+P on board testing

JRC, TUG, Autostrade road side testing

M+P road side testing

TUG test bench testing

No.No.1313/17/17

Fraction rolling noise and propulsion noise

• Depends on speed and vehicle class

20 40 60 80 100 120 140 160vehicle speed [km/h]

soun

d po

wer

leve

l L W

category 1 - Light motor vehicles

propulsion noiserolling noisetotal noise

5 dB

10 20 30 40 50 60 70 80 90 100vehicle speed [km/h]

soun

d po

wer

leve

l L W

category 3 - Heavy duty vehicles

propulsion noiserolling noisetotal noise

5 dB

No.No.1414/17/17

Vehicle acceleration

• Increase in propulsion noise; not in rolling noiserolling & propulsion noise at 30 km/h

light motor vehicle (cat. 1)

40

50

60

70

80

90

25 40 63 100

160

250

400

630

1000

1600

2500

4000

6300

1000

0frequency [Hz]

soun

d po

wer

leve

l [dB

(A)]

propulsion noise @ 30 km/h

rolling noise @ 30 km/h

total noise @ 30 km/h

prop. noise @ 30 km/h,acceleration +1.5 m/s^2total noise @ 30 km/h,acceleration +1.5 m/s^2

No.No.1515/17/17

Effect of road gradient on propulsion noise

approximate effect on overall LWP level

-12 -8 -4 0 4 8 12

road gradient (%)

⎠L W

P,gr

adie

nt [d

B(A

)]

cat. 1 & 4cat. 2 & 3

No.No.1616/17/17

Effect of illegal silencers on propulsion noise level,standard: 1% for cars and trucks, 35% for motorcycles.Effect of an IRESS is 12 dB on propulsion noise

⎪⎪⎩

⎪⎪⎨

⎧

−

−

=

⋅−⋅=Δ

4category for%100

%35%

3 and 2 1,category for%100

%1%

2429 2,

IRESS

IRESS

p

ppL

IRESS

IRESSIRESSIRESSWP

No.No.1717/17/17

conclusion

• A complete and state-of-the-art model for the noise emission of an EU vehicle is developed. - Defined in Lw, fits into propagation calculations- Easy to use and to implement in computerized noise mapping tools- Allows adaptation to local situations and to future developments in

vehicle technology (such as hybrid cars)

• Reports available on IMAGINE website:- www.imagine.org

• First noise maps show the need for serious action plans• Depending on action plans, many agglomerations may urge

EC/ECE on noise reduction of tyres and vehicles