GB/T 17697-2014
Acoustics.Determination of sound power radiated into a duct by fans and other air-moving devices.In-duct method (English Version)
- Standard No.
- GB/T 17697-2014
- Language
- Chinese, Available in English version
- Release Date
- 2014
- Published By
- General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China
- Latest
- GB/T 17697-2014
- Replace
- GB/T 17697-1999
- Scope
- General This standard specifies a method for determining the sound power radiated from the inlet and outlet ends of fans and other ventilation equipment connected to ducts into ducts with anechoic ends. This method is applicable to fans whose air temperature is -50°C~+70°C and which radiate steady-state wide, narrow-band and discrete frequency noise. The test pipe diameter ranges from 0.15 m to 2 m. Appendix H and Appendix I respectively describe the methods for measuring the sound power of fans in test pipes with diameters d<0.15 m and d>2 m. The determination method of this standard limits the maximum average flow velocity of the airflow at the microphone head position depending on the type of microphone protective cover: --foam dome: 15 m/s; --nose cone: 20 m/s; --sampling Tube: 40 m/s. If these values are exceeded, the above-mentioned microphone guards are not sufficient to suppress turbulent pressure pulsations (see 3.9). During the sound power test, the airflow parameters shall be measured according to the method specified in GB/T 1236. Therefore, test ducts are usually fitted with a "star" fairing at the fan outlet to minimize eddy currents (see 5.2.9 and 7.3). For large fans installed in accordance with GB/T 1236 Type C, the rectifying grid can be omitted, but only under the condition that the vortex angle does not exceed 15° (Appendix J illustrates the method for measuring the vortex angle). Applicable sound source types The test methods described in this standard are applicable to sound sources where at least one end of the fan is connected to the duct, as well as other fan/muffler combinations or fan combinations known as "black boxes". Fans and other equipment involved in this standard include: -- centrifugal fans connected to pipelines; -- axial flow fans connected to pipelines; -- mixed flow fans connected to pipelines; -- air handlers connected to pipelines; -- suction fans connected to pipelines Dust device;--air conditioning device connected to the pipeline;--hot air blower connected to the pipeline. This standard is also applicable to other aerodynamic sound sources where the airflow delivered by the auxiliary fan is stable and the signal-to-noise ratio between the sound pressure and the turbulent pressure fluctuation in the test pipeline is not lower than 6 dB (see 7.2.1), such as plenum boxes, dampers and throttling device. GB/T 25516 regulations
GB/T 17697-2014 Referenced Document
- GB/T 1236-2000 Industrial fans-Performance testing using standardized airways
- GB/T 15173-2010 Electroacoustics.Sound calibrators
- GB/T 3240-1982 Preferred frequencies for the acoustical measurement
- GB/T 3241-2010 Electroacoustics.Octave-band and fractional-octave-band filters
- GB/T 3785.1-2010 Electroacoustics-Sound level meters- Part 1:Specifications
GB/T 17697-2014 history
- 2014 GB/T 17697-2014 Acoustics.Determination of sound power radiated into a duct by fans and other air-moving devices.In-duct method
- 1999 GB/T 17697-1999 Acoustics--Determination of sound power radiated into a duct by fans--In-duct method
