GB/T 1859.4-2025Reciprocating internal combustion engines - Measurement of sound power level using sound pressure - Part 4: Survey method for use in situ (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for standardization work Part 1: Structure and drafting rules for standardization documents" Drafting.

This document is Part 4 of GB/T 1859 "Reciprocating internal combustion engines - Determination of sound power levels by the sound pressure method".

The following parts are published.

--- Part 1: Engineering law;

--- Part 2: Simple method;

--- Part 3: Semi-anechoic chamber precision method;

--- Part 4: Simple method for field measurement.

This document replaces GB/T 1859.4-2017 "Reciprocating internal combustion engines - Determination of sound power levels by sound pressure method - Part 4: Using standard sound pressure level Compared with GB/T 1859.4-2017, in addition to structural adjustments and editorial changes, the main technical changes are as follows.

--- Changed "Terms and Definitions" and added symbols (see Chapter 3, Chapter 3 of the 2017 edition);

--- Deleted "Criteria for acoustic suitability of the test environment" (see 4.3 of the 2017 edition);

--- Changed "Working Conditions" (see Chapter 6, Chapter 6 of the 2017 edition);

--- Changed "Measurement distance" (see 7.4, 7.4 of the 2017 edition);

--- Changed the "Microphone location suitability criteria" (see 7.7, 7.7 of the 2017 edition).

This document is equivalent to ISO 6798-3:2022 "Reciprocating internal combustion engines - Determination of sound power levels by sound pressure method - Part 3: Field measurements" "Simplified Method".

The following minimal editorial changes have been made to this document.

--- In order to coordinate with the existing standard, the name of the standard is changed to "Determination of sound power level of reciprocating internal combustion engines by sound pressure method Part 4.

A Simple Method for Field Measurement.

Introduction

The sound power level measurement results are basically independent of the test environment and the installation conditions of the sound source. This is the use of sound power level to characterize various types of machines and an important cause of equipment noise radiation.

Sound power level is used for the following purposes.

--- Indication of the machine radiated noise under specified conditions;

---Verification of noise label value;

--- Comparison of radiated noise of machines of various models and sizes;

--- Comparison with the noise limits specified in the purchase contract or specification;

--- Development of engineering measures to reduce machine radiated noise (generally, the frequency band sound power level is also required);

--- Prediction of noise sound pressure level at specified locations.

GB/T 1859 "Determination of sound power level of reciprocating internal combustion engines by sound pressure method" is a guide to measure the sound power level of reciprocating internal combustion engines by measuring the sound power level on the measurement surface of the envelope sound source.

The standard for calculating sound power level based on pressure level is designed to obtain sound power level measurement results with a specified accuracy level and consists of four parts.

--- Part 1: Engineering method. The purpose is to obtain the sound power level measurement results of Class 2 accuracy level, which can be used for acceptance test and also can be used to formulate engineering measures.

--- Part 2: Simple method. The purpose is to obtain sound power level measurement results with a level 3 accuracy level, which can be used for comparative tests.

--- Part 3: Semi-anechoic chamber precision method. The purpose is to obtain the sound power level measurement results of Class 1 accuracy level, which can be used for calibration the test can also be used to formulate engineering measures.

--- Part 4: Simple method for field measurement. The purpose is to obtain the sound power level measurement results of level 3 accuracy, which can be used for comparison test.

Table 1 gives three accuracy levels of sound power level determination methods, the measurement results are accurate to 0.1dB.

The A-weighted sound power level can be measured with an accuracy of Class 3.

Table 2 gives the measurement uncertainty limits of sound power level (upper limit of reproducibility standard deviation). They reflect the overall measurement uncertainty.

The total effect is not included, but the sound power level changes caused by factors such as the installation conditions and operating conditions of the measured sound source are excluded.

In the noise control of reciprocating internal combustion engines, relevant parties (including manufacturers, installers and users, etc.) should conduct effective Only when clear acoustic quantities are obtained under the specified measurement conditions and the specifications of this document are used, can the acoustic information be effectively communicated.

Therefore, when selecting these standards, the noise measurement purpose and measurement conditions should be taken into consideration.

Make the best choice.

Table 1 Sound power level measured by sound pressure method specified in GB/T 1859 series standards

parameter

GB/T 1859.1

Engineering Law

Level 2

GB/T 1859.2

Simple method

Level 3

GB/T 1859.3

Semi-anechoic chamber precision method Level 1 GB/T 1859.4 Simple method for on-site measurement Level 3 Reference standards ISO 3744 ISO 3746 ISO 3745 ISO 3747 Test environment

1 Reflective surface

Approximate free field above 1 reflective surface Sound field above 1 reflective surface Sound field above Sound field with multiple reflecting surfaces Sound source volume Unlimited, depends on Test environment Unlimited, depends on Test environment Better than test 0.5% of the room volume Unlimited, depends on the test environment

Table 1 Sound power levels measured by the sound pressure method specified in the GB/T 1859 series of standards (continued)

parameter

GB/T 1859.1

Engineering Law

Level 2

GB/T 1859.2

Simple method

Level 3

GB/T 1859.3

Semi-anechoic chamber precision method Level 1 GB/T 1859.4 Simple method for on-site measurement Level 3 Background noise criterion a deltaLpA>=6.0dB K1A<=1.3dB deltaLpA>=3.0dB K1A<=3.0dB deltaLpA>=10.0dB K1A<=0.5dB deltaLpA>=3.0dB K1A<=3.0dB Test environment acoustics Suitability criteria K2A<=4.0dB K2A<=7.0dB Special requirements Special requirements Proper microphone position Sexual Standards b s(L'pAm)<=1.0dB s(L'pAm)<= 2dB s(L'pAm)<=1/2dB s(L'pAm)<=2.0dB Measuring instruments Sound Level Meters/Filters/Sound Calibrators Level 1/Level 1/Level 1Level 2/Level 2/Level 1Level 1/Level 1/Level 1Level 2/Level 2/Level 1 Available sound power levels A-weighted or A-weighted in frequency bands use Sound power level acceptance test;

Development of engineering measures Sound power level comparison test Sound power level calibration test;

Development of engineering measures Sound power level comparison test Note.

K1A. Background noise correction.

K2A. Environmental correction.

deltaLpA. The difference between the surface sound pressure level measured when the sound source being measured is working and the background noise sound pressure level.

s(L'pAm). Standard deviation of the mean sound pressure level.

a For background noise correction, see 8.3.2.

b For the criteria for suitability of microphone location, see 7.7.

c Instrument requirements, calibration and use are described in Chapter 5.

Table 2 Uncertainty limits for sound power level measurement (upper limit of reproducibility standard deviation)

Center frequency

Octave 1/3 octave

GB/T 1859.3

Reproducibility standard deviation dB GB/T 1859.1 Reproducibility standard deviation dB GB/T 1859.2 Reproducibility standard deviation dB GB/T 1859.4 Reproducibility standard deviation dB 63 50~80 2.0 5.0 125 100~160 1.5 3.0 250.200~315 1.5 2.0 500 400~630 1.5 1.5 1000~4000 800~5000 1.0 1.5 8000 6300~10000 1.5 2.5 A weighting 1.0 1.5 3.0 4.0 Determination of sound power level of reciprocating internal combustion engines using the sound pressure method Part 4: Simple method for field measurement

1 Scope

This document specifies the method for determining the sound power level of reciprocating internal combustion engines - a simplified method for field measurements.

This document applies to reciprocating internal combustion engines within the scope of ISO 3046-1 and to other internal combustion engines for which no appropriate standard exists.

Note. In this document, unless otherwise specified, reciprocating internal combustion engine is referred to as "engine".

2 Normative references

The contents of the following documents constitute the essential clauses of this document through normative references in this document.

For referenced documents without a date, only the version corresponding to that date applies to this document; for referenced documents without a date, the latest version (including all amendments) applies to this document.

ISO 3046-1 Reciprocating internal combustion engines — Performance — Part 1: Calibration and test methods for power, fuel consumption and oil consumption Note. GB/T 6072.1-2008 Reciprocating internal combustion engine performance Part 1: Calibration and test methods for power, fuel consumption and oil consumption General Additional requirements for engines (ISO 3046-1:2002, IDT) ingmethod) ISO 6926 Acoustics - Requirements for the performance and calibration of standard sound sources for the determination of sound power levels power levels) Note. GB/T 4129-2003 Acoustics Performance and calibration requirements for standard sound sources used in sound power level determination (ISO 6926:1999, IDT) IEC 60942 Electroacoustics-Soundcalibrators Note. GB/T 15173-2010 Electroacoustic sound calibrators (IEC 60942:2003, IDT) IEC 61260-1 Electroacoustics - Octave-band and fractional-octave-band filters - Part 1: Specifications IEC 61672-1 Electroacoustics-Soundlevelmeters-Part 1: Specification Specifications) Note. GB/T 3785.1-2023 Electroacoustics Sound Level Meters Part 1: Specification (IEC 61672-1:2013, IDT)

3 Terms, definitions and symbols