基于RHC-7水听器对液体中固体目标声波探测研究

为了实现液体中微小固体目标在线探测,设计了基于RHC-7水听器采集系统探测液体中微小固体目标的新方案。探测系统利用脉冲激励瓶体产生混响声波,RHC-7水听器浸入瓶内液体中采集声波,经UTC1250VA带通滤波器放大滤波后,对采集的混响声波信号进行Mallat多分辨率时频分析,分离提取微弱的探测目标信号。由于液体中固体目标粘滞声吸收和散射声吸收会影响水声信号的频谱分布,计算探测信号各频段频谱与基准信号的相关度,确定检测阈值,并作为识别瓶体中有无固体目标的指标。实验表明,该方法简单、实用,可实现探测一定尺度的悬浮和沉淀目标。

Design of Acoustic Detection System for Detecting Solid Target in Liquid Based on RHC-7 Hydrophone

In order to realize the on line detection of micro solid targets in liquid, a new scheme of detecting micro solid targets in liquid based on RHC-7 hydrophone acquisition system was designed in this work. The bottle body produced the reverberation sound wave with the method of pulse excitation in detection system, which was collected and amplified by UTC1250VA amplifier system. The time-frequency analysis of the acoustic signal was carried out with the method of Mallat multi resolution, then the weak target signal was separated and extracted. The detected solid target influenced the spectrum distribution due to the viscous sound absorption and scattering sound absorption, then the correlation between detection signal and the reference signal was calculated to determine the detection threshold, which was an effective method to identify solid target in liquid. The experimental results show that the acoustic detection system is not only simple and practical, but also can detect the certain scale of target of the suspension and precipitation in liquid.