1、BSI Standards Publication PD ISO/TS 19425:2015 Reciprocating internal combustion engines Measurement method for air cleaners Sound power level of combustion air inlet noise and insertion loss using sound pressurePD ISO/TS 19425:2015 PUBLISHED DOCUMENT National foreword This Published Document is the
2、 UK implementation of ISO/TS 19425:2015. The UK participation in its preparation was entrusted to Technical Committee MCE/14, RIC engines. A list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary
3、 provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2015. Published by BSI Standards Limited 2015 ISBN 978 0 580 87181 8 ICS 27.020 Compliance with a British Standard cannot confer immunity from legal obligations. This Published Document wa
4、s published under the authority of the Standards Policy and Strategy Committee on 31 December 2015. Amendments issued since publication Date Text affectedPD ISO/TS 19425:2015 ISO 2015 Reciprocating internal combustion engines Measurement method for air cleaners Sound power level of combustion air in
5、let noise and insertion loss using sound pressure Moteurs alternatifs combustion interne Mthode de mesure du bruit des purificateurs dair Niveau de puissance sonore du bruit dentre dair de combustion et de perte dinsertion utilisant une pression sonore TECHNICAL SPECIFICATION ISO/TS 19425 Reference
6、number ISO/TS 19425:2015(E) First edition 2015-12-15PD ISO/TS 19425:2015ISO/TS 19425:2015(E)ii ISO 2015 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2015, Published in Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized other
7、wise 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 ISOs member body in the country of the requester. ISO copyright office
8、Ch. de Blandonnet 8 CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyrightiso.org www.iso.orgPD ISO/TS 19425:2015ISO/TS 19425:2015(E)Foreword iv Introduction v 1 Scope . 1 2 Normative references 1 3 T erms and definitions . 1 4 Test environment . 5 4.1 Gener
9、al . 5 4.2 Criterion for background noise. 5 4.3 Criterion for acoustic adequacy of test environment 6 5 Instrumentation 6 5.1 General . 6 5.2 Calibration 6 5.3 Application . 6 6 Installation and operation conditions . 7 6.1 General . 7 6.2 Installation condition 7 6.3 Operation condition 8 7 Measur
10、ement . 8 7.1 General . 8 7.2 Measurement uncertainty . 9 7.3 Characteristic source dimension 10 7.4 Measurement radius .10 7.5 Measurement surface and area 10 7.6 Microphone arrays 10 8 Calculation .12 8.1 General 12 8.2 Calculation of sound power level .12 8.2.1 Mean time-averaged sound pressure l
11、evels 12 8.2.2 Corrections for background noise .13 8.2.3 Corrections for environmental .13 8.2.4 Surface time-averaged sound pressure levels .14 8.2.5 Sound power levels .14 8.3 Calculation of insertion loss .14 9 Information to be recorded 15 10 Test report 16 Annex A (normative) Qualification pr
12、oc edur es for the ac oustic en vir onment .17 Annex B (normative) Calculation of A-weighted sound power levels from frequency band levels 20 Annex C (normative) Sound power level under reference meteorological conditions22 Bibliography .24 ISO 2015 All rights reserved iii Contents PagePD ISO/TS 194
13、25:2015ISO/TS 19425:2015(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body intereste
14、d 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 Com
15、mission (IEC) on all matters of electrotechnical standardization. The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents
16、 should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible f
17、or identifying any or all such patent rights. Details of any patent rights identified during the development of 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 information given for the
18、 convenience of users and does not constitute an endorsement. For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Fo
19、reword - Supplementary information The committee responsible for this document is ISO/TC 70, Internal combustion engines.iv ISO 2015 All rights reservedPD ISO/TS 19425:2015ISO/TS 19425:2015(E) Introduction This Technical Specification specifies methods for measuring the sound power level of combusti
20、on air inlet noise and the insertion loss of air cleaners installed on reciprocating internal combustion engines. Sound power level of combustion air inlet noise, insertion loss, and transmission loss are parameters to characterize the acoustic performance of air cleaners. Sound power levels of comb
21、ustion air inlet noise and insertion loss are important parameters to characterize the acoustic matching performance of air cleaners and reciprocating internal combustion engines. Transmission loss is the difference in sound power level of combustion air inlet noise between the noise before and afte
22、r transmitting through the air cleaner, which is the parameter to characterize the acoustic performance of the air cleaner itself and is irrelevant with the reciprocating internal combustion engine. The matching parameters of the sound power level of combustion air inlet noise and the insertion loss
23、 are used in this Technical Specification as the measurement parameters. The enveloping surface method of this Technical Specification is applicable for engineering method (accuracy grade 2) and survey method (accuracy grade 3). Engineering method allows the determination of the A-weighted and frequ
24、ency-band sound power level, survey method allows the determination of the A-weighted sound power level. The measurement result of sound power level is rounded to the nearest 0,1 dB. In the combustion air inlet noise control of air cleaner, the relevant members (including manufacturer, installation,
25、 and the user) should make effective communication of acoustic information which is obtained by measurement. The measurement result is valid only in the specified measurement conditions by using the instrumentation as specified in this Technical Specification to obtain a clear acoustic value. Engine
26、ering method or survey method may be selected according to the purpose of noise measurement and measurement conditions. The measurement surface defined based on the characteristics of noise source under test in this Technical Specification is spherical. To meet the requirements of the measurement un
27、certainty, this Technical Specification gives specification of the distance from the installation location of the noise source to the reflecting plane (ground). ISO 2015 All rights reserved vPD ISO/TS 19425:2015PD ISO/TS 19425:2015Reciprocating internal combustion engines Measurement method for air
28、cleaners Sound power level of combustion air inlet noise and insertion loss using sound pressure 1 Scope This Technical Specification specifies the measurement method and requirements for combustion air inlet noise of air cleaners which are installed on reciprocating internal combustion engines, inc
29、luding laboratory measurement (engineering method and survey method) and site measurement (survey method). This Technical Specification applies to all air cleaners installed on reciprocating internal combustion engines (reciprocating internal combustion engine is referred to as engine except particu
30、lar explanation in the following text) falling within the field of application of ISO 3046-1 and/or other air induction installation. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated
31、references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 3046-1, Reciprocating internal combustion engines Performance Part 1: Declarations of power, fuel and lubricating oil consumptions, and test metho
32、ds Additional requirements for engines for general use ISO 3046-3, Reciprocating internal combustion engines Performance Part 3: Test measurements ISO 6926, Acoustics Requirements for the performance and calibration of reference sound sources used for the determination of sound power levels IEC 6094
33、2, Electroacoustics Sound calibrators IEC 61260, Electroacoustics Octave-band and fractional-octave-band filters IEC 61672-1, Electroacoustics Sound level metersPart 1: Specifications 3 T erms a nd definiti ons For the purposes of this document, the terms and definitions defined in ISO 3046-1, ISO 3
34、046-3, ISO 6926, IEC 60942, IEC 61260 and IEC 61672-1 and the following apply. 3.1 sound pressure p difference between instantaneous pressure and static pressure Note 1 to entry: It is expressed in pascals. TECHNICAL SPECIFICATION ISO/TS 19425:2015(E) ISO 2015 All rights reserved 1PD ISO/TS 19425:20
35、15ISO/TS 19425:2015(E) 3.2 sound pressure level L p ten times the logarithm to the base 10 of the ratio of the square of the sound pressure (3.1), p, to the square of a reference value, p 0 where the reference value, p 0 , is 20 Pa Note 1 to entry: If specific frequency and time weightings, as speci
36、fied in IEC 61672-1, and/or specific frequency bands are applied, this is indicated by appropriate subscripts, e.g. L pAdenotes the A-weighted sound pressure level. Note 2 to entry: It is expressed in decibels. 3.3 time-averaged sound pressure level L p,T ten times the logarithm to the base 10 of th
37、e ratio of the time average of the square of the sound pressure (3.1), p, during a stated time interval of duration, T (starting at t 1and ending at t 2 ), to the square of a reference value, p 0 where the reference value, p 0 , is 20 Pa Note 1 to entry: In general, the subscript “T” is omitted sinc
38、e time-averaged sound pressure levels are necessarily determined over a certain measurement time interval (3.5). Note 2 to entry: Time-averaged sound pressure levels are often A-weighted, in which case they are denoted by L pA,T , which is usually abbreviated to L pA . Note 3 to entry: It is express
39、ed in decibels. 3.4 surface time-averaged sound pressure level mean(energy average) of the time-averaged sound pressure levels (3.3) over all the microphone positions, or traverses, on the measurement surface (3.11), with the background noise correction (3.13), K 1 , and the environmental correction
40、 (3.14), K 2 , applied Note 1 to entry: It is expressed in decibels. 3.5 measurement time interval T portion or a multiple of an operational period or operational cycle of the noise source under test for which the time-averaged sound pressure level (3.3) is determined Note 1 to entry: It is expresse
41、d in seconds.2 ISO 2015 All rights reservedPD ISO/TS 19425:2015ISO/TS 19425:2015(E) 3.6 a c o u s t i c f r e e f i e l d sound field in a homogeneous, isotropic medium free of boundaries Note 1 to entry: In practice, an acoustic free field is a field in which the influence of reflections at the bou
42、ndaries or other disturbing objects are negligible over the frequency range of interest. 3.7 r e f le c t i n g pl a ne sound-reflecting planar surface on which the noise source under test is located 3.8 a c o u s t i c f r e e f i e l d o v e r a r e f l e c t i n g p l a n e acoustic free field (3
43、.6) in the half-space above an infinite reflecting plane (3.7) in the absence of any other obstacles 3.9 frequency range of interest the frequency range of octave bands with nominal mid-band frequencies from 63 Hz to 8 000 Hz (including one-third octave bands with mid-band frequencies from 50 Hz to
44、10 000 Hz) 3.10 measurement radius r radius of a spherical measurement surface (3.11) Note 1 to entry: It is expressed in metres. 3.11 measurement surface hypothetical spherical surface of area, S, on which the microphone positions are located at which the sound pressure levels (3.2) are measured, e
45、nveloping the noise source under test 3.12 background noise noise from all sources other than the noise source under test Note 1 to entry: Background noise includes contributions from airborne sound, noise from structure-borne vibration, and electrical noise in the instrumentation. 3.13 background n
46、oise correction K 1 correction applied to the mean (energy average) of the time-averaged sound pressure levels (3.3) over all the microphone positions on the measurement surface (3.11), to account for the influence of background noise (3.12) Note 1 to entry: The background noise correction is freque
47、ncy dependent; the correction in the case of a frequency band is denoted by K 1f , where f denotes the relevant mid-band frequency and that in the case of A-weighting is denoted by K 1A . Note 2 to entry: It is expressed in decibels. 3.14 environmental correction K 2 correction applied to the mean (
48、energy average) of the time-averaged sound pressure levels (3.3) over all the microphone positions on the measurement surface (3.11), to account for the influence of reflected sound Note 1 to entry: The environmental correction is frequency dependent; the correction in the case of a frequency band i
49、s denoted by K 2f , where f denotes the relevant mid-band frequency, and that in the case of A-weighting is denoted by K 2A . ISO 2015 All rights reserved 3PD ISO/TS 19425:2015ISO/TS 19425:2015(E) Note 2 to entry: It is expressed in decibels. 3.15 sound power W through a surface, product of the sound pressure (3.1), p, and the component of the particle velocity, u n , at a point on the surface in the directi
