A measurement system and method for jet noise of a water-filled pipeline

Abstract

The invention discloses a measurement system and a measurement method for jet noise of a water filling pipe. The measurement system comprises the water filling pipe, a reverberation box, a polymethyl methacrylate board and a hydrophone vertical line array. The reverberation box has a steel cuboid structure and is filled with water. The top end of the reverberation box is not provided with a cover, and the bottom is supported by a crossbeam. The polymethyl methacrylate board is mounted in the reverberation box and divides the reverberation box into two parts, namely a jet area and a testing area. The water filling pipe is placed at the jet area of the reverberation box. The hydrophone vertical line array is placed at the testing area in the reverberation box. The measurement system and the measurement method have advantages of reliably eliminating pipe wall radiation noise generated by factors such as water current impact of the water filling pipe or water pump vibration, eliminating flow noise which is generated by hydrophone motion in space averaging. The measurement method for jet noise of the water filling pipe eliminates the effect of a dummy sound caused by water current impact on the hydrophone in measuring the jet noise by a free field. Advantages of a reverberation method are used, thereby reducing workload in measuring the radiation sound power of the jet noise of the water filling pipe by the free field.

Description

technical field [0001] The invention belongs to the field of acoustic measurement, in particular to a measurement system and method for jet noise of a water-filled pipeline. Background technique [0002] Underwater jet noise is generally caused by the water in the water-filled pipe submerged in the water being sprayed from the nozzle at a certain flow rate, and the radiation noise generated by the interaction between the fast-sprayed water flow and the still water due to the sharp mixing of the two. The magnitude of jet noise (non-cavitation) is generally small, and it is easy to be submerged by the radiation noise of pipe wall vibration. If the continuous moving hydrophone in the reverberation method is used for spatial averaging to collect jet noise, the The low-speed flow noise generated by continuous motion will be mixed in the jet noise, which is very unfavorable for the experimental research of underwater jet noise. Patent (CN 104132727 A)---a high-rise / super high-ris...

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Problems solved by technology

The magnitude of jet noise (non-cavitation) is generally small, and it is easy to be submerged by the radiation noise of pipe wall vibration. If the continuous moving hydrophone in the reverberation method is used for spatial averaging to collect jet noise, the The low-speed flow noise generated by continuous motion will be mixed in the jet noise, which is very unfavorable for the experimental research of underwater jet noise

Patent (CN 104132727 A)---a high-rise / super high-rise building drainage pipe noise testing system and testing method and patent (CN 101368845 A)---drainage pipe noise detection room and its detection method, all involving drainage pipes Radiation noise test in the air; Wang Man (see Applied Acoustics, 2003(1): 35-38) carried out research on sound radiation control of liquid-filled pipeline noise, but only placed hydrophone sound intensity array at the nozzle to evaluate the noise reduction Acoustic performance of the device, without involving the measurement system and measurement method of the jet noise generated by the rapid injection of the water flow of the water-filled pipeline into the still water

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