GB/T 14369-2011Acoustics - Measurement methods of insertion loss, echo reduction and sound absorption coefficient for underwater acoustical material samples (English PDF)

Foreword

This standard was drafted in accordance with GB/T 1.1-2009 given rules. This standard is GB/T 14369-1993 "acoustic underwater acoustic material sample insertion loss and echo reduction measuring method" amendment. The standards are compared with the GB/T 14369-1993 The following major changes.

--- The standard name "acoustic underwater acoustic material sample insertion loss measurement method and echo reduction" by the words "acoustic underwater acoustic material Sample insertion loss and echo reduction and methods of measurement of the absorption coefficient ";

--- Information about the underwater acoustic absorption coefficient of the sample material derived content measuring method;

--- Increasing the digital measuring device pulse tube method and the free-field method;

--- Increased broadband pulse pile up in the free-field method;

--- Increasing the pressure tank near-field method;

--- Remove the original Appendix A, the contents written to standard text. This standard replaces GB/T 14369-1993 "acoustic underwater acoustic material sample insertion loss measurement method and echo reduction." This standard was proposed by the Chinese Academy of Sciences. This standard by the National Standardization Technical Committee of Acoustics (SAC/TC17) centralized. This standard drafting unit. China Shipbuilding Industry Corporation seventh fifteen Research Institute, Chinese Academy of Sciences Institute of Acoustics. The main drafters of this standard. Li water, Luoma Qi, Zhao, Yan Yi, Mo Kihei, Cui, Wang Jin, Miao Rongxing, Lo Chun Mei, Panghai Ou. Acoustic underwater acoustic material sample insertion loss, echo Measurement methods and reduce the absorption coefficient

1 Scope

GB/T 14369-2011 is the Chinese national standard on acoustics - measurement methods of insertion loss, echo reduction and sound absorption coefficient for underwater acoustical material samples, in the field of metrology and measurement. The /T suffix marks it as a recommended standard: it is not compulsory by itself, but it becomes binding as soon as a contract, a tender or a customer specification calls it up - which in practice is how most foreign buyers meet it. It was issued on 30 December 2011 by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China; Standardization Administration of China, and has been in force since 1 May 2012. Classification: ICS 17.140, CCS A59. This page is published from the official record of the standard held by the Chinese standards administration: the identification, the dates, the classification and the issuing body are taken from there. The clause text, the tables and the numeric limits are in the document itself, which is delivered complete in English translation.

This standard specifies the pulse tube method, free-field method and the pressure tank near field measurement of underwater acoustic material sample insertion loss and acoustic echo reduction Measurement methods, measurement conditions factor, measuring apparatus and measurement uncertainty. This standard applies to the sound of water sample materials and components (hereinafter referred to as sample) insertion loss, echo reduction and measuring the absorption coefficient, wherein the pulse Red tube method for measuring a small sample of the free-field method and the pressure tank near-field method is suitable for measuring large sample of different frequency bands.

2 Normative references

The following documents for the application of this document is essential. For dated references, only the dated version suitable for use herein Member. For undated references, the latest edition (including any amendments) applies to this document.

GB/T 3223-1994 Acoustics underwater acoustic transducer free-field calibration method

GB/T 3947-1996 Acoustics Terminology

3 Terms and Definitions

GB/T 3947-1996 and defined the following terms and definitions apply to this document.

3.1 Pulse tube pulsetube In which the emission, propagation and reception of acoustic pulses, for measuring the acoustic characteristics of the sample material or component parameters of water-filled rigid walled gold Metal tube.

Note. The pulse tube is generally thick-walled tube, placed vertically, the wall thickness of the thick-walled tube means is not less than the inner radius of the tube.

3.2 Free field freefield Homogeneous and isotropic medium, boundary effect can be neglected sound field.

3.3 Pressure tank pressuredvessel In which the emission, propagation and reception of acoustic pulses, for measuring the acoustic characteristics of the sample material or component parameters can be added just hydrostatic water-filled Seal tank.

Note. The tank is generally placed vertically in the tank is generally placed in the order from bottom to top respectively transmit transducers, hydrophones, samples, and acoustic hydrophone wedge.

3.4 Sound pressure transmission coefficient soundpressuretransmissioncoefficient At a given frequency and environmental conditions, water medium plane sound wave incident to the infinite plate-like sample surface that transmits sound waves and the incident sound pressure Compression ratio.

Note. the actual measurement at the edge effect is negligible, the sample is equivalent to a finite infinite sample.