标题: BS EN ISO3745:2003 [打印本页] 作者: 玻璃杯里水晶 时间: 2011-5-1 09:28 标题: BS EN ISO3745:2003 Acoustics —Determination of sound power levels of noise sources using sound pressure —precision methods for
anechoic and hemi-anechoic rooms
Contents
Page
Foreword. v
Introduction ..vi
1 Scope.1
2 Normative references..1
3 Terms and definitions ..2
4 Measurement uncertainty.5
5 Test room requirements .6
5.1 General .. 6
5.2 Criterion for adequacy of the test room 7
5.3 Criterion for background noise 7
5.4 Criterion for temperature. 7
5.5 Humidity correction . 7
6 Instrumentation 7
6.1 General .. 7
6.2 Calibration 8
7 Installation and operation of source under test .8
7.1 General .. 8
7.2 Source location 8
7.3 Source mounting 8
7.4 Auxiliary equipment . 9
7.5 Operation of source undertest. 9
8 Measurement of sound pressure levels for the determination of sound power level . 10
8.1 General 10
8.2 Measurement surface 10
8.3 Microphone positions 11
8.4 Conditions of measurement 12
8.5 Data to be obtained 13
8.6 Correction for background sound pressure levels.. 13
8.7 Calculation of surface sound pressure level. 14
9 Measurement of single-event sound pressure levels for the determination of sound
energy level. 15
10 Calculation of sound power level and sound energy level 16
10.1 Sound power level. 16
10.2 Sound energy level 17
11 Information to be recorded.. 17
11.1 General 17
11.2 Sound source undertest . 18
11.3 Acoustic environment. 18
11.4 Instrumentation 18
11.5 Acoustic data. 18
12 Information to be reported .. 19
Annex A (normative) General procedures for qualification of anechoic and hemi-anechoic rooms..20
Annex B (normative) Alternative qualification procedure for anechoic and hemi-anechoic rooms
for the determination of sound power levels of specific noise sources 26
Annex C (normative) Array of microphone positions in a free field. 28
Annex D (normative) Array of microphone positions in a free field over a reflecting plane. 29
Annex E (normative) Coaxial circular paths of microphones in a hemi-free field. 31
Annex F (normative) Meridional paths of microphones in a hemi-free field.. 32
Annex G (normative) Spiral paths of microphones in a hemi-free field. 34
Annex H (normative) Calculation of A-weighting sound power level from one-third-octave-band
sound power levels .. 35
Annex I (normative) Calculation of directivity index and directivity factor. 37
Annex J (informative) Measurement uncertainty.. 38
Annex K (informative) Guidelines for the design of test rooms 41
Bibliography 43作者: 采女孩的大蘑菇 时间: 2011-5-1 09:28