Tiêu chuẩn iso 00362 3 2016

INTERNATIONAL STANDARD ISO 362-3 First edition 2016-07-01 Measurement of noise emitted by accelerating road vehicles — Engineering method — Part 3: Indoor testing M and N categories Mesurage du bruit émis par les véhicules routiers en accélération — Méthode d’expertise — Partie 3: Essais l’intérieur de catégories M et N Reference number ISO 362-3:2016(E) © ISO 2016 ISO 362-3:2016(E) COPYRIGHT PROTECTED DOCUMENT © ISO 2016, Published in Switzerland All rights reserved Unless otherwise specified, no part o f this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission Permission can be requested from either ISO at the address below or ISO’s member body in the country o f the requester ISO copyright o ffice Ch de Blandonnet • CP 401 CH-1214 Vernier, Geneva, Switzerland Tel +41 22 749 01 11 Fax +41 22 749 09 47 copyright@iso.org www.iso.org ii © ISO 2016 – All rights reserved ISO 362-3:2016(E) Contents Page Foreword v Introduction vi Scope Normative references Terms and definitions Symbols and abbreviated terms Acceleration for vehicles of categories M1 and M2 having a maximum authorized mass not exceeding 500 kg, and of category N1 5.1 General 5.1.1 Applicability and conditions 5.1.2 Calculation of total engine power 5.1.3 Battery state o f charge 5.2 Calculation of acceleration 5.2.1 Calculation procedure for vehicles with manual transmission, automatic transmission, adaptive transmission, and continuously variable transmission (CVT) tested with locked gear ratios 5.2.2 Calculation procedure for vehicles with automatic transmission, adaptive transmission, and CVT tested with non-locked gear ratios 5.3 Calculation of the target acceleration 5.4 Calculation of the reference acceleration 5.5 Partial power factor, kP 6 Instrumentation 6.1 Instruments for acoustical measurement 6.1.1 General 6.1.2 Calibration 6.2 Con formity with requirements 6.3 Instrumentation for speed measurement 6.4 Meteorological instrumentation 7 Test room requirements 7.1 General 7.2 Test room dimensions 7.3 Acoustical qualification o f the room 10 7.3.1 General 10 7.3.2 Validation o f free-field conditions 10 7.3.3 Qualification procedure 13 7.4 Condition o f the floor 14 7.5 Cooling, ventilation, air temperature, exhaust gas management 14 7.6 Background noise 14 Dynamometer requirements 15 8.1 Type o f texture o f the rollers 15 8.2 Diameter of the rollers 15 8.3 Reproducibility o f the pass-by dynamics 15 8.4 Single-axle or multi-axle operation 16 8.5 Noise emission limit under operating conditions produced by the dynamometer rollers 16 Test procedures 16 9.1 General 16 9.2 Microphone array — Hardware and so ftware 16 9.3 Vehicle fixing system 17 9.4 Conditions of the vehicle 17 9.4.1 General conditions 17 9.4.2 Test mass of the vehicle 17 © ISO 2016 – All rights reserved iii ISO 362-3:2016(E) 18 Operating conditions 19 9.5.1 Vehicles of categories M1, M2 having a maximum authorized mass not exceeding 500 kg, and N1 19 9.5.2 Vehicles of categories M2 having a maximum authorized mass exceeding 500 kg, M3, N2 and N3 19 9.6 Measurement readings and reported values 20 9.6.1 General 20 9.6.2 Data compilation 21 9.6.3 Vehicles of categories M1 and M2 having a maximum authorized mass not f 21 9.6.4 Vehicles of categories M2 having a maximum authorized mass exceeding 500 kg, M3, N2, and N3 21 21 10 Test methods and test report 22 10.1 General 22 10.2 Variant A 22 10.2.1 General 22 10.2.2 Power train noise 22 22 10.2.4 Calculation of the total vehicle noise using variant A 23 10.3 Test report 23 Annex A (normative) Validation of method 24 Annex B (normative) Procedure for measurement, evaluation, and calculation of tyre/road noise when using variant A 28 Annex C (informative) Procedure for measurement, evaluation, and calculation of tyre/ road noise when using variant B 41 Annex D (informative) Measurement uncertainty — Framework for analysis according to ISO/IEC Guide 98-3 43 Annex E (informative) Room length deviation from recommendation 49 Bibliography 51 9.5 Tyre s electio n and tyre co nditio n exceeding 0 kg, and o 9.7 M eas urement uncertainty 0.2 iv catego ry N Tyre/ro ad no is e © ISO 2016 – All rights reserved ISO 362-3:2016(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies) The work o f preparing International Standards is normally carried out through ISO technical committees Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters o f electrotechnical standardization The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part In particular the di fferent approval criteria needed for the di fferent types o f ISO documents should be noted This document was dra fted in accordance with the editorial rules o f the ISO/IEC Directives, Part (see www.iso org/directives) Attention is drawn to the possibility that some o f the elements o f this document may be the subject o f patent rights ISO shall not be held responsible for identi fying any or all such patent rights Details o f any patent rights identified during the development o f the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso org/patents) Any trade name used in this document is in formation given for the convenience o f users and does not constitute an endorsement For an explanation on the meaning o f ISO specific terms and expressions related to formity assessment, as well as information about ISO’s adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www.iso org/iso/foreword.html The committee responsible for this document is ISO/TC 43, Acoustics, Subcommittee SC 1, Noise ISO 362 consists of the following parts, under the general title Measurement of noise emitted by accelerating road vehicles — Engineering method: — Part 1: M and N categories — Part 2: L category — Part 3: Indoor testing M and N categories © ISO 2016 – All rights reserved v ISO 362-3:2016(E) Introduction The external sound emission of a vehicle is one out of a multitude of requirements that need to be protection reasons, the sound emission should be reduced under all relevant driving conditions considered by manu facturers during design and development o f vehicles For health and environmental However, there is a growing awareness that vehicles must not be too quiet either to ensure that they are still acoustically perceivable by pedestrians and don’t endanger them as they might be missed To meet all these demands, an e fficient test site is needed that can be operated the whole year round independent o f weather conditions or other outside factors In many countries, the meteorological conditions are so adverse that outdoor testing on a classical proving ground is only possible in a very limited timeframe While this was acceptable in the past, the increasing workload in the future will make it nearly impossible to the complete development o f a vehicle on a single test track at one particular place However, per forming sound emission tests on various test tracks highly increases the uncertainty and multiplies the workload for a manu facturer This part o f ISO 362 gives specifications for an indoor noise test bench and a test procedure that delivers precise results for indoor testing, comparable to a certified type approval test track The results are intended to be within the run-to-run variation of the actual valid exterior noise test described in ISO 362-1, which is the test standard used for type approval o f vehicles An indoor test bench requires tight specifications for the equipment and set up, such as the acoustical treatment, the microphone arrays, the roller bench, the adjustment for the dynamic behaviour o f the vehicle on the roller test bench, the preconditioning of the vehicle, as well as the thermal conditions for testing Special treatment needs to ensure that all rolling sound components of the tire are comparable to the rolling sound on a road sur face as specified in ISO 10844 and as applied in type approvals It is conceivable that in the future, certain sound emissions of vehicles (like e.g minimum sound emission o f electric vehicles) can be verified on an indoor test bench, as the natural background noise might prohibit testing on a classical outdoor test track The specifications set forth in this part o f ISO 362 could be transferred to a future minimum noise test procedure This part o f ISO 362 provides all necessary specifications and procedures to ensure comparability between todays common and well accepted testing on outdoor test tracks with future indoor facilities It incorporates all relevant International Standards for equipment, measurement uncertainty, and test procedures vi © ISO 2016 – All rights reserved INTERNATIONAL STANDARD ISO 362-3:2016(E) Measurement of noise emitted by accelerating road vehicles — Engineering method — Part 3: Indoor testing M and N categories Scope This part o f ISO 362 specifies an engineering method for measuring the noise emitted by road vehicles o f categories M and N by using a semi anechoic chamber The specifications are intended to achieve an acoustical correlation between testing the exterior noise of road vehicles in a semi anechoic chamber and outdoor testing as described in ISO 362-1 This part of ISO 362 provides all necessary specifications and procedures for indoor testing to obtain results which are comparable to typical run-to-run variations o f measurements in today’s type approval tests This part o f ISO 362 provides a method designed to meet the requirements o f simplicity as far as they are consistent with the reproducibility o f results under the operating conditions o f the vehicle NOTE The results obtained by this method give an objective measure o f the noise emitted under the specified conditions o f test It is necessary to consider the fact that the subjective appraisal o f the noise annoyance o f di fferent classes o f motor vehicles is not simply related to the indications o f a sound measuring system As annoyance is strongly related to personal human perception, physiological human conditions, culture, and environmental conditions, there is a large variation and annoyance is there fore not use ful as a parameter to describe a specific vehicle condition NOTE I f measurements are carried out in rooms which not fulfill the requirements stated in this part o f ISO 362, the results obtained can deviate from the results using the specified conditions Normative references The following documents, in whole or in part, are normatively re ferenced in this document and are indispensable for its application For dated re ferences, only the edition cited applies For undated re ferences, the latest edition o f the re ferenced document (including any amendments) applies ISO 362-1:2015, Measurement of noise emitted by accelerating road vehicles — Engineering method — Part 1: M and N categories ISO 1176, Road vehicles — Masses — Vocabulary and codes ISO 2416, Passenger cars — Mass distribution ISO 3745, Acoustics — Determination of sound power levels and sound energy levels of noise sources using sound pressure — Precision methods for anechoic rooms and hemi-anechoic rooms ISO 10844, Acoustics  —  Specification  of  test  tracks  for  measuring  noise  emitted  by  road  vehicles  and  their tyres ISO 26101, Acoustics  —  Test  methods  for  the  qualification  of  free-field  environments IEC 60942, Electroacoustics — Sound calibrators IEC 61672-1, Electroacoustics  —  Sound  level  meters  —  Part  1:  Specifications © ISO 2016 – All rights reserved ISO 362-3:2016(E) IEC 61672-3, Electroacoustics — Sound level meters — Part 3: Periodic tests ISO/IEC Guide 98-3, Uncertainty of measurement — Part 3: Guide to the expression of uncertainty in measurement (GUM) Terms and definitions For the purposes o f this document, the terms and definitions given in ISO 362-1, ISO 1176, and ISO 2416, and the following apply 3.1 pre-acceleration application of acceleration control device prior to the virtual line AA’ for the purpose of achieving stable acceleration between line AA’ and line BB’ on the test track Note to entry: See Figure 3.2 virtual test track length l virtual length of test track used in the calculation of acceleration Note to entry: The virtual length o f test track from line AA’ to line BB’ is denoted lAB and the virtual length from line PP’ to line BB’ is lPB Note to entry: See Figure Symbols and abbreviated terms Table lists the symbols used in this part of ISO 362 and the clause number where they are used for the first time Table — Symbols used and corresponding clauses Symbol Unit Clause BB’ — 3.1 C dabsorb droller FCor FTEX h kcrs kP kwot lAB lmin,room lPB lveh Lcrs rep dB/°C B.2.4 7.2 5.1.1 C.4 D.2 D.2 D.2 5.5 D.2 3.2 7.2 3.2 7.2 D.2 a, aPTN AA’ m/s — m m dB(A) % — — — m m m m dB(A) B.3.3 3.1 Designation vehicle acceleration (at power train noise measurement) line perpendicular to vehicle travel which indicates beginning of zone in which to record sound pressure level during test line perpendicular to vehicle travel which indicates end of zone in which to record sound pressure level during test temperature correction coe fficient thickness of absorbing elements diameter o f dynamometerroller correction for tyre/road noise in variant B texture of the test track surface relative air humidity weighting factor partial power factor weighting factor virtual length of test section for calculation of acceleration from AA’ to BB’ minimum length of the test room virtual length of test section for calculation of acceleration from PP’ to BB’ length of vehicle reported vehicle sound pressure level at constant speed © ISO 2016 – All rights reserved ISO 362-3:2016(E) Table Symbol Unit LFRN dB(A) LPTN dB(A) LPTNi dB(A) LTRN dB(A) LTRNi dB(A) LTRNo dB(A) LTVN dB(A) LTVNi dB(A) LTVNo dB(A) Lurban dB(A) Lwot rep dB(A) m ac max kg md kg m fa load unladen kg m kerb kg mra load unladen kg m ref kg m ro kg mt kg m target kg m unladen kg m xload kg Mwheel Nm n BB’ n n PP’ n roller AA‘ test i n stat pair hPa Pref hPa Ptest hPa PP’ Qref kg Qtest kg r0 m rx m Tair Texhaust Tintake Ttrack v vAA’ r/m i n d yn r/m i n r/m i n r/m i n r/m i n — °C °C °C °C km/ h km/ h Clause B.4.1 10.2.4 C.3 10.2.4 C.3 C.4 10.2.4 B.6 C.5 D.1 D.2 9.4.2.2.3 9.4.2.2.3 9.4.2.2.3 9.4.2.2.3 9.4.2.2.3 9.4.2.2.3 9.4.2.2.3 9.4.2.2.3 9.4.2.2.3 9.4.2.2.3 9.4.2.2.3 D.2 10.3 D.2 10.3 5.1.1 D.2 D.2 B.2.3 B.2.3 3.2 B.2.3 B.2.3 7.3.2.4 7.3.2.4 D.2 D.2 D.2 D.2 B.4.2 5.1.1 © ISO 2016 – All rights reserved (continued) Designation free rolling noise sound pressure level power train noise sound pressure level power train noise sound pressure level indoor tyre/ro ad noi s e s ou nd pre s s u re le vel tyre/ro ad noi s e s ou nd pre s s u re le vel i ndo or tyre/ro ad noi s e s ou nd pre s s u re le vel o utdo o r total vehicle noise sound pressure level total vehicle noise sound pressure level indoor total vehicle noise sound pressure level outdoor reported vehicle sound pressure level representing urban operation reported vehicle sound pressure level at wide-open throttle m a xi mu m re a r a x le c ap ac ity mass of driver unladen front axle load kerb mass of the vehicle unladen rear axle load kerb mass + 75 kg for the driver mass in running order vi r tu a l or ac tu a l p hys ic a l te s t m a s s o f the veh icle , th at i s u s e d a s a n i nput fo r s i mu l ati ng the veh icle tra n s ient b eh aviou r b y the dyn a mome ter control s ys tem target mass of the vehicle unladen vehicle mass extra loading torque on the wheel engine speed when the reference point passes BB’ engine speed during wide-open-throttle (wot) tests engine speed when the reference point passes PP’ i engine speed during cruise tests and in the approach of wot tests barometric air pressure ro tatio n a l s p e e d o f the dyn a mo me ter ro l ler fo r the te s t r u n i n fl ation pre s s u re re co m mende d b y the m a nu fac tu rer te s t i n fl ation pre s s u re line perpendicular to vehicle travel which indicates location of microphones weight of the vehicle to be tested indoor weight o f the tyre te s t veh icle reference path length of the centre measurement position path length to the microphone at distance x air temperature temp eratu re o f e x h au s t s ys tem temperature of intake air temperature of the test track surface vehicle speed vehicle speed when reference point passes line AA’ ISO 362-3:2016(E) Table (continued) Symbol Unit vAA’ test i km/ h vBB’ km/ h vd yn km/ h vPP’ km/ h vPTN km/ h vstat vtest vTRN km/ h km/ h km/ h m wsingle,room m wdual,room m wveh m x m xmicro m dB wroom α ,   β — γ — δ Δ Lx dB(A) dB(A) dB(A) dB(A) dB(A) Δ n r/m i n Δ s Δ L me a s u re s ys Δ Ln Δ Δ Δ Δ Δ Δ Ls LTI dB L crsmax dB L urbanmax dB L wotmax dB L max — ε — ζ ϑ λ cut off L urban σ m °C m dB Clause 5.1.1 10.3 D.2 10.3 B.5 D.2 9.5.1.2 B.4.3 7.2 7.2 7.2 7.2 B.3.3 7.3.2.4 B.4.2 B.4.3 B.4.3 D.2 D.2 D.2 B.3.3 7.3.2.4 D.2 D.2 D.2 D.2 D.2 D.2 B.4.3 B.3.3 B.2.4 7.2 D.2 Designation vehicle speed when reference point passes line AA’ for the test run i (see 5.1 f f f vehicle speed when reference point or rear of vehicle passes line BB’ (see 5.1 f f f vehicle speed during wide-open-throttle tests vehicle speed when reference point passes line PP’ (see 5.1 f of reference point) vehicle speed at the power train noise measurement indoor vehicle speed during cruise tests and in the approach of wot tests target vehicle test speed or de fi n itio n o re erence p o i nt) or de fi n itio n o re erence p o i nt) o r de fi n ition veh icle s p e e d at the tyre/ro ad noi s e me a s u rement outdo or width of the room width o f the ro o m fo r a s i n gle - s ide d width o f the ro o m fo r a du a l- s ide d fac i l ity fac i l ity width of the vehicle vehicle position on the (virtual) test track p o s ition o f the m ic ro p hone i n the a r rays i n d ri vi n g d i re c tion co e ffic ients o f fre e rol l i n g no i s e co e ffic ient o f the e xac t to rque i n fluence co e ffic ient o f the e xac t to rque i n fluence me a s u rement s ys tem er ror qu a ntity en gi ne s p e e d er ror qu a ntity acceleration p o s ition er ro r qu a ntity torque i n fluence o f the s o u nd p re s s u re le vel rel ative s o u nd p re s s u re le vel de c ay at p o s ition x m a xi mu m p a me ter va r i ab i l ity i n the te s t s itu atio n fo r the engi ne s p e e d m a xi mu m p a me ter va r i ab i l ity i n the te s t s itu atio n fo r the acceleratio n position maximum total deviation of sound pressure level maximum total deviation of Lcrs maximum total deviation of Lurban maximum total deviation of Lwot co e ffic ient o f the e xac t to rque i n fluence co e ffic ient o f s ta nda rd torque i n fluence measured temperature of test track surface wavelen g th at the c ut- o ff fre quenc y standard deviation of Lurban © ISO 2016 – All rights reserved ISO 362-3:2016(E) T he rel ate d tyre/ro ad noi s e s ou nd pre s s u re level free rolling noise L TRN (a v x ϑ ) = α ( x) + β ( x) ⋅ , , , lg    v PTN 50 LTRN is calculated from the data set as follows: ( x)  km h (B.8)  and either e xac t torque i n fluence + γ ( x ) ⋅ a PTN ( x) + δ ( x) ⋅ a PTN ( x) + ε ( x) or s tandard torque i n fluence + ⋅ ζ ⋅ a PTN ( x ) + ζ ⋅ a PTN ( x ) and temperature correction +C ) ⋅ (2 ° C − ϑ where a PTN is the vehicle acceleration at the power train noise measurement; C i s the temp eratu re corre c tion co e fficient; vPTN x α , γ ,     a re the co e ffic ients o f β δ ,   ε ζ ϑ Figure B.9 38 is the vehicle speed at the power train noise measurement; is the x-position of the vehicle; fre e rol l i ng noi s e; a re the co e ffic ients o f the exac t torque i n fluence; i s the co e ffic ient o f the s tanda rd torque i n fluence; is the measured temperature of the test track surface s hows an e xample for the c a lc u l ate d tyre/ro ad noi s e a nd the rel ate d fre e rol l i ng noi s e © ISO 2016 – All rights reserved ISO 362-3:2016(E) Key X x-position, m Y sound pressure level, dB(A) free rolling noise tyre/road noise Figure B.9 — Example for calculated tyre/road noise and related free rolling noise B.6 Disturbance noise correction of power train noise measurement When evaluating the power train noise indoor, it shall be checked whether the remaining tyre/roller noise of the slicks is at least 10 dB below the measured maximum power train noise If not, a correction shall be applied This check should be carried out even i f slick tyres are used to minimize that disturbance noise First step for this check is to determine the coe fficients o f free rolling noise indoor analogously to the procedure on the test track outside (see B.4.2 ) A determination o f the torque influence coefficients is not necessary since the torque influence can be neglected for slicks Next step is the calculation of the power train noise measurement related free rolling noise as mentioned in B.5 If the distance between the two curves in the area of the maximum level is less than 10 dB, the free rolling noise has to be subtracted from the measurement of the power train noise to achieve the corrected power train noise sound pressure level, LPTN L PTN where LTVNi LFRN = 10  ⋅   lg L TVN i 10 − L FRN 10 10     dB (B.9) is the total vehicle noise sound pressure level indoors; is the free rolling noise sound pressure level © ISO 2016 – All rights reserved 39 ISO 362-3:2016(E) Figure B.10 shows a n exa mple for a pro ce du re to che ck i f a d i s tu rb a nce noi s e corre c tion i s ne ce s s ar y Vehicle with slick tyres on roller bench Measure noise with Measure cruise Measure free rolling wide open throttle (WOT) noise (CRS) noise (FRN) CRS – FRN > dB WOT – FRN > dB yes Engine noise yes Engine noise NO TE no = measurement measurement ⊝ FRN Engine noise = measurement measurement ⊝ FRN for Engine noise = = ⊝ s ta nd s no energe tic a l s ub trac tio n Figure B.10 — Example for a procedure to check if a disturbance noise correction is necessary 40 © ISO 2016 – All rights reserved ISO 362-3:2016(E) Annex C (informative) Procedure for measurement, evaluation, and calculation of tyre/ road noise when using variant B C.1 General When using variant B (see 10.1 ) , the me tho d u s e s an i ndo or me as u rement o f a veh icle a na lo gou s ly to I S O 62 -1 with norma l tyre s and a corre c tion fi lter to come to a n outdo or pre d ic tion T he corre c tion fi lter s l l b e eva luate d once and c a n then b e u s e d for a cer tai n range o f veh icle/tyre combi nation s C.2 Principle Figure C.1 shows, in general, how to derive an outdoor prediction from an indoor measurement Key indoor measurement outdoor prediction correction Figure C.1 — Principle of variant B C.3 Decomposition of L TVNi A decomposition of the total vehicle noise indoor, LTVNi, into the both main components power train noise indoor, LPTNi LTRNi be done for LTRNi It is assumed that LPTNi equals the power train noise outdoor, LPTNo , a nd tyre/ro ad noi s e i ndo or, © ISO 2016 – All rights reserved , i s ne ce s s ar y, b e c au s e the corre c tion ne e d s on ly to 41 ISO 362-3:2016(E) For th i s pu rp o s e, it i s ne ce s s a r y no t on ly to p er form accelerate d me a s u rements on the dynamome ter (ana lo gou sly to I S O 62 -1) but a l s o rol l i ng me as u rements o f the tyre/rol ler noi s e (without p ower trai n noise measurements) The component power train noise sound pressure level indoor LPTNi is determined as follows:  L TVNi L TRNi    10 − 10 10  dB L PTN i = 10 ⋅ lg  10     (C.1) where LTVNi LTRNi is the total vehicle noise sound pressure level indoors; i s the tyre/ro ad noi s e s ou nd pre s s u re level i ndo ors C.4 Correction of L TRNi To come to a pre d ic tion o f the tyre/ro ad noi s e s ou nd pre s s u re level outdo ors , LTRNo , the tyre/ro ad noise indoor, LTRNi, shall be corrected with the so called correction function, FCor = f (x), which shall be defi ne d s ep arately LTRNo for e ach s i ngle ro om/track combi nation = LTRNi + FCor (C.2) where LTRNi FCor i s the tyre/ro ad noi s e s ound pre s s ure level i ndo ors; is the correction function for the total vehicle noise sound pressure level C.5 Calculation of L TVNo The prediction of the totel vehicle noise sound pressure level outdoor, LTVNo 10.2.4, the energetical sum of the corrected LTRNo and LPTNi:  L TRNo L PTNi     10 + 10 10  dB L TVNo = 10 ⋅ lg  10    , i s then, a na lo gou s ly to (C.3) where LTRNo LPTNi 42 i s the tyre/ro ad noi s e s ound pre s s ure level outdo ors; is the power train noise sound pressure level indoors © ISO 2016 – All rights reserved ISO 362-3:2016(E) Annex D (informative) Measurement uncertainty — Framework for analysis according to ISO/IEC Guide 98-3 D.1 General T he me as u rement pro ce du re i s a ffe c te d b y s evera l fac tors c au s i ng d i s tu rb a nce that le ad to variation s in the resulting level observed for the same vehicle under test The source and nature of these p er turb ation s are no t comple tely known and s ome ti me s a ffe c t the end re s u lt i n a non-pre d ic table way T he accep te d format for expre s s ion o f uncer ta i ntie s genera l ly a s s o ci ate d with me tho d s o f me as u rement i s that given i n I S O/I E C Gu ide -3 T h i s format i ncorp orate s a n u ncer ta i nty budge t, i n wh ich a l l the variou s s ou rce s o f u ncer tai nty a re identi fie d a nd qua nti fie d, a nd from wh ich the combi ne d s tandard fol lowi ng fac tors: u ncer tai nty c an b e ob tai ne d Uncer ta i ntie s are due to the — va riation s i n me as u rement device s , s uch a s s ou nd level me ters , c a l ibrators , and s p e e d me a s u ri ng — va riation s i n veh icle s p e e d and i n veh icle p o s ition duri ng the p a s s -by ru n s; — measurement of Lurban; devices; va riation s in lo ca l envi ron menta l cond ition s that a ffe c t s ou nd prop agation at the — va riation s i n lo c a l envi ron menta l cond ition s that a ffe c t the charac teri s tics o f the s ou rce; — e ffe c ts o f envi ron menta l cond ition s (ai r pre s s u re , a i r den s ity, hu m id ity, of ti me a i r temp eratu re) th at i n fluence the me ch an ica l cha rac teri s tic s o f the s ou rce, mai n ly engi ne p er formance; — e ffe c ts o f envi ron menta l cond ition s that i n fluence the s ou nd pro duc tion o f the propu l s ion s ys tem (ai r pre s s ure, r den s ity, hu m id ity, r temp eratu re) and the rol l i ng noi s e (tyre and ro ad s u r face temperature, humid surfaces); — te s t s ite prop er tie s (te s t s u r face te xtu re and ab s orp tion, s u r face grad ient) 9.7 f the manufacturer The variations in the urban sound pressure level of identical vehicles of a production process are outside the scope of this part of ISO 362 repre s ents the u ncer tai nty a s s o ci ate d with th i s p ar t o T he uncer ta i nty de term i ned accord i ng to I S O 62 I t e s no t cover the u ncer tai nty a s s o ci ate d with the va riation i n the pro duc tion pro ce s s e s o f T he u ncer tai nty e ffe c ts sources (see 9.7): a) for i ndo or te s ti ng c an b e group e d i n th re e are as comp o s e d o f the fol lowi ng r u n-to -r u n variation s: uncer tai nty due to cha nge s i n the veh icle op eration with i n s e c utive ru n s a nd me as u rement s ys tem u ncer ta i nty; cha nge s i n cl i matic cond ition s a nd i n b ackgrou nd noi s e level s are prac tic a l ly negl igible; b) d ay-to - day vari ation s: u ncer tai nty due to ch ange s in the veh icle op eration, change s me a s urement s ys tem p er formance over longer p erio d s , changi ng prop er tie s o f the te s t in the faci l ity over ti me, a nd s ma l l cha nges i n cl i matic cond ition s th roughout the ye ar; c) s ite -to - s ite va ri ation s: u ncer tai nty due to d i fferent veh icle op eration, me a s u rement s ys tem s , te s t s ite lo c ation s , a nd ro ad s ur face ch arac teri s tics (tyre/ro ad noi s e data T he s ite -to - s ite variation compri s e s u ncer ta i nty s ou rce s compri s e s uncer ta i nty s ou rce s © ISO 2016 – All rights reserved from from from d i fferent te s t tracks) a) , b) , and c) T he day-to - day va riation a) a nd b) 43 ISO 362-3:2016(E) D.2 Expression for the calculation of measurement uncertainties for measured sound pressure levels of vehicles in urban operation The general expression for the calculation of the urban-operation sound pressure level Lurban is given by Formula (D.1): Lurban = Lwot rep − kP (Lwot rep − Lcrs rep) (D.1) where Lwot rep is the reported A-weighted sound pressure level from wide-open-throttle tests; Lcrs rep is the reported A-weighted sound pressure level from cruise tests, if applicable; kP is the partial power factor, if applicable NOTE For vehicles o f category M2 with authorized mass exceeding 500 kg, and categories M3, N2, and N3, kP is always zero For the creation o f a su fficiently precise uncertainty model, it is necessary to subdivide the sound pressure level, Lwot, crs rep, into the main source contributions: power train noise and tyre/road noise: L wot,crs rep  L = ⋅ lg  10   PTN 10 + 10 L TRN 10    dB  (D.2) where LPTN is the A-weighted sound pressure level from power train noise contribution; LTRN is the A-weighted sound pressure level from tyre/road noise contribution From this fact, the weighting factor kwot,crs is defined as: L k wo t, crs = 10 L PT N (D.3) 10 wo t crs , re p 10 Both main contributions LPTN and LTRN can be described with respect to the most important systematic dependencies as follows: LPTN = f (n dyn, n stat, x, Texhaust, Tintake, Tair, pair, h) (D.4) 10 and LTRN = f (vdyn, vstat, Mwheel, x, Ttrack, FTEX, Tair, pair, h) (D.5) where FTEX is the texture of the test track surface; h is the relative air humidity; Mwheel is the torque on the wheel; ndyn is the engine rotational speed during wide-open-throttle (WOT) tests; 44 © ISO 2016 – All rights reserved ISO 362-3:2016(E) n stat is the engine rotational speed during cruise tests and in the approach of wot tests; pair is the barometric air pressure; x is the x-position of the vehicle; Tair is the air temperature; Texhaust f Tintake is the temperature of the intake air; Ttrack is the temperature of the test track surface; v is the vehicle speed during wide-open-throttle tests; vstat is the vehicle speed during cruise tests and in the approach of WOT tests Note that the parameters of speed, rotational speed and wheel torque are dependent on air temperature, i s the temp eratu re o the e xhau s t s ys tem; d yn r pre s s u re and relative hu m id ity a s wel l: v , n , Mwheel = f (Tair, pair, h) d yn T he (D.6) d yn p ar tia l quantitie s Δ d i fferenti a l L… o f the s e fu nc tion s yield s and c a n b e l i ne arly approxi mate d for to ge ther with the p arame ters the s i ngle error s ma l l i nputs , e g : ∆ L n = ∂L ⋅ ∆ n ; ∆ L s = ∂L ⋅ ∆ s ; … ∂n ∂s (D.7) where ¶L ¶n Dn is the partial differential for the example engine speed; i s the ma xi mum p a rame ter va ri abi l ity i n the te s t s ituation for the exa mple engi ne s p e e d For an acc u rate c a lc u lation, it has to d i s ti ngu i sh b e twe en s ou rce - s p e c i fic and glob a l quantitie s I n source distribution Therefore, the weighting factors kwot and kcrs are used The maximum total deviation of Lurban maxLurban L maxLurban maxLwot kP max Lwot max L crs) contras t to the glob a l quantitie s , the s ou rce - s p e ci fic qua ntitie s sh a l l b e weighte d accord i ng to the , Δ Δ me a s u re s ys , , i nclud i ng the me as u rement s ys tem error quantity c an b e expre s s e d i n a s i mpl i fie d way: Δ = Δ − ⋅ (Δ (D.8) − Δ where   ∂L ∂L ⋅ ∆ n + ∂L ⋅ ∆ T ∂L ⋅ ∆ T   = ⋅ ⋅ ∆ n + + ∆ max L wot k wot  ∂n dyn ∂n stat ∂T exhaust ∂T intake    intake exhaust  + (1 − k ) ⋅  ∂L ⋅ ∆v + ∂L ⋅ ∆ v + ∂L ⋅ ∆Μ + ∂ L ⋅ ∆ T + ∂L ⋅ ∆ F ∂F ∂v ∂Μ ∂T  ∂v + ∂L ⋅ ∆s + ∂L ⋅ ∆Tair + ∂L ⋅ ∆p air + ∂L ⋅ ∆h + ∆L measure sys ∂s ∂Tair ∂p air ∂h wot dyn stat wheel wheel © ISO 2016 – All rights reserved track tra c k TEX TEX 45    ISO 362-3:2016(E)  ∂L  ∂L ⋅ ∆ T ∂L ⋅ ∆ T  + ∆ max L crs = k crs ⋅  ∂n ⋅ ∆n stat + ∂T exhaust ∂T intake    exhaust intake   + (1 − k crs ) ⋅  ∂L ⋅ ∆v stat + ∂L ⋅ ∆Ttrack + ∂L ⋅ ∆FTEX   ∂Ttrack ∂FTEX  ∂v + ∂L ⋅ ∆Tair + ∂L ⋅ ∆p air + ∂L ⋅ ∆h + ∆L measure sys ∂Tair ∂p air ∂h Furthermore it is assumed that all possible results for f f f L urban : approxi mately 9,7 % o a s s u mp tion i mpl ie s σL urban a l l va lue s a re with i n the range o L urban a re norma l ly d i s tribute d ± the ma xi mu m to ta l devi ation o f and L urban that This or the s tandard devi ation σ = ∆ max L urban (D.9) NOTE The inputs included in the Formulae (D.7) and (D.8) to allow for errors are those thought to be applicable according to the state of knowledge at the time when this part of ISO 362 was developed, but further research could reveal that there are others NO TE T he e s ti m ate d va lue s o f the delta fu nc tio n s c a n p r i nc ip a l l y b e p o s itive or ne gative a ltho ugh the y a re considered to be zero for the given measurement (see Table D.1) Their uncertainties are not additive for the purpose of determining a measurement result Figure D.1 variation 46 shows an e xample for the den s ity and d i s tribution fu nc tion s for an i ndo or ru n-to -ru n © ISO 2016 – All rights reserved ISO 362-3:2016(E) Key X deviation, dB Y error, dB f distribution function f dens ity limits NO TE unctio n o r a coverage p ro b ab ility o f % T he s ta nda rd de vi ation i s , d B ; the e xp a nde d de viation the maximum error is 0,7 dB fo r a coverage p rob ab i l ity o f % i s , d B ; Figure D.1 — Example for density and distribution functions for an indoor run-to-run variation D.3 Uncertainty budget Table D.1 give s an u ncer tai nty budge t for de term i nation o f u rb an s ound pre s s ure level u ncer ta i nty Table D.1 — Uncertainty budget for determination of urban sound pressure level uncertainty Quantity Estimate maximum deviation Δ dB Lwot rep Δ kP Δ Lwot rep − Δ L crs rep ∂ L ∂ n ∂ L ∂ n Lwot rep kP Δ Lwot rep − Δ L crs rep Standard uncertainty Probability distribution ui dB Sensitivity coe fficient Uncertainty contribution ci u i ci Δ Lwot rep ⋅ Δ L crs rep kP ⋅ ∆ n dyn — kwot ⋅ ∆ n stat — kwot kcrs © ISO 2016 – All rights reserved dB , 47 ISO 362-3:2016(E) Table D.1 (continued) Quantity Estimate maximum deviation ∂ ∂ L T ∂ L ∂ T ∂ L ∂ v ∂ L ∂ v kwot kcrs , v dyn — kwot ⋅ ∆ v s tat — kwot kcrs — kwot — kwot kcrs — kwot kcrs L ⋅ ∆ L L L ⋅ ∆ L ∂ pair ∂ L ∂ h ⋅ ∆ ⋅ ∆ ⋅ ∆ Ttrack FTE X s , , , — ⋅ ∆ ¤ air L ⋅ ∆ Μ wheel Tair — pair — h — L me a s u re s ys dB , — ∂ Δ dB Tintake FTE X ∂ dB ⋅ ∆ ∂ ∂ u i ci ⋅ ∆ ∂ ∂ ci ui kwot kcrs ¤ track s Uncertainty contribution — œ wheel ∂ Sensitivity coe fficient Texhaus t ∂ ∂ Probability distribution ⋅ ∆ ∂ ∂ Standard uncertainty — From the i nd ividua l u ncer tai nty contribution s , u i ci, the combi ne d s tandard u ncer ta i nty, u , can be ca lc u late d accord i ng to I S O/I E C Gu ide -3 , ta ki ng i nto account p o tentia l correlation s b e twe en variou s input quantities NO TE T he u ncer ta i nty e va lu atio n de s c r ib e d rep re s ents a fra mewo rk th at p rovide s u s e fu l i n fo r m ation to users of this part of ISO 362 This information represents the state of technical information at the time of f Formula (D.1) and all interactions between such terms pub l ic ation Fu r ther work i s ne ce s s a r y to provide u ncer ta i nty i n or m atio n on a l l ter m s i n D.4 Expanded uncertainty of measurement T he e xp a nde d uncer ta i nty, the appropri ate coverage 48 U, i s c a lc u late d by mu ltiplyi ng the combi ne d s tanda rd u ncer tai nty, fac tor for u , with the cho s en coverage prob abi l ity a s de s c rib e d i n I S O/I E C Gu ide -3 © ISO 2016 – All rights reserved ISO 362-3:2016(E) Annex E (informative) Room length deviation from recommendation As described in this part of ISO 362, the technological advancements in room acoustics, vehicle dynamometer simulation, and digital signal processing allow to conduct indoor vehicle exterior noise measurements with high accuracy Testing conducted at various indoor facilities resulted in good correlation with similar tests performed at common outdoor test sites While all indoor facilities used or testing complied with this part o f ISO 362, many o f them had deviations regarding the dimensions as recommended in 7.2 This annex provides the in formation and requirements necessary to cater for these deviations of indoor testing facilities The recommended length of a room depends on the following factors f — The length o f the test track to be simulated: As a general rule, the length o f the room depends on the length o f the longest vehicle to be tested plus the length o f the test track (20 m) For a typical vehicle of m length, the length of track is 25 m — The lowest frequency o f concern: As a general rule, the microphones should be positioned in a distance of one quarter wavelength from the absorbing walls, while the absorbing media should have a nominal thickness o f one quarter o f the wavelength o f the lowest frequency o f concern As an example, i f a vehicle is fitted with a four-cylinder engine with a lower engine rotational speed o f 000 r/min, the lowest firing frequency o f the engine is approximately 34 Hz To design a semianechoic room with a low- frequency cut-o ff o f 34 Hz, the nominal wedge thickness o f the absorbing media is 2,6 m For this example, the outer width o f the test room should be approximately 20 m and the outer length o f the test room should be approximately 30 m Such large rooms exist, but are not common Some manu facturers and laboratories use smaller rooms for indoor pass-by noise measurement that give relevant levels for the specific application and the vehicles being tested The expected location o f the peak levels and the influence o f the lowest frequency o f interest are the parameters that determine the size of the room required The indoor test operation described in this part o f ISO 362 is designed to measure the pass-by noise indoor on the locations where the relevant sound pressure levels are expected The expected location of the peak levels depends on the vehicle to be tested and the testing condition (cruise, wide-open throttle) As shown in the example of Figure E.1 , the peak levels are located at −1 m and m distance from line PP’ © ISO 2016 – All rights reserved 49 ISO 362-3:2016(E) Key X distance from line PP’, m Y sound pressure level, dB(A) peak level Figure E.1 — Example of two typical pass-bys for two different peak level locations T he s e p a s s -b y te s ts cou ld b e p er forme d i n a ro om that wou ld cover on ly m o f the te s t track leng th from −5 m to +10 m d i s ta nce from l i ne PP ’ To c ater for the s ma l ler d i men s ion s o f s uch te s t ro om s , the peak levels shall be evaluated with caution though to avoid missing them An appropriate test can be derived from the following: — — a comp ari s on with a n outdo or p a s s -b y noi s e; an ex trap olation o f the p a s s -b y u s i ng repre s entative(s) m ic rophone(s) T he ti me evolution o f the s ound level dep end s d i re c tly on the s ou nd level o f the veh icle and its d i s tance to the m icrophone s Knowing the speed evolution of the sound level of the vehicle, it is possible to extrapolate it for a distance evolution evaluation of the sound level This information permits also — a s tandard d i fference b e twe en ma xi mu m s ou nd level s a nd s ou nd level s at b order lo c ation T he choice o f one te s t or a combi nation o f te s ts to fi rm the p e a k level lo c ation re qu i re s a s p e c i fic development of a procedure of validation 50 © ISO 2016 – All rights reserved ISO 362-3:2016(E) Bibliography [1] [2] [3] [4] [5] ISO 1585, Road vehicles — Engine test code — Net power ISO 5725 (all parts), Accuracy (trueness and precision) of measurement methods and results ISO 6344-1, Coated abrasives — Grain size analysis — Part 1: Grain size distribution test ISO 13325:2003, Tyres — Coast-by methods for measurement of tyre-to-road sound emission ISO 80000-3, Quantities and units — Part 3: Space and time [7] ACEA, Auto Alliance, EMA JAMA 2013 G lobal N.C.P International Institute of Noise Control Engineering, Report from I-INCE Technical Study Group Noise Control Eng J 2004, 52 (6) [8] D onavan P.R The E ffect o f Pavement Type on Low Speed Light Vehicle Noise Emission Paper No 2005-01-2416 Society o f Automotive Engineers, 2005 [6] [9] Worldwide F uel C h arter E nz W., & S te ven H Round Robin Test on test tracks as proposed in ISO/TC 43/SC 1/WG 27 Report No 10505993/01, FIGE, Herzogenrath, Germany, 1992 [10] M oore D.B Evaluation of the Revised ISO 362 Standard for Vehicle Exterior Noise Measurement Paper No 2005-01-2417 Society o f Automotive Engineers, 2005 [11] S ch um acher [12] R.F., P h anue f K.G., H ale y W.J SAE and ISO Site Variability SAE Noise Vibration Conference Report Paper Mo 951361 S te ven H Investigations on Improving the Method of Noise Measurement for Powered Vehicles Report Number 10506067 by order o f the Germany Federal Environmental Agency, 1999 [13] S te ven H Further Noise Reductions for Motorized Road Vehicles Workshop o f the German Federal Environmental Agency, 2001 [14] S te ven H WMTC Technical Report TRANS/WP.29/ 2005/55 2005 main/welcwp29 htm © ISO 2016 – All rights reserved Presentation within the www.unece org/trans/ 51 ISO 362-3:2016(E) ICS  17.140.30 Price based on 51 pages © ISO 2016 – All rights reserved