深海热液声学原位测温仪中的声源选择研究

Study on Selection of Sound Sources in Acoustic In-situ Detector of Temperature for Deep Sea Hydrothermal Vent

为了选择合适的声源信号,提高深海热液声学原位测温仪的测量精度,针对热液口的声学特性,在分析了信号频率范围和声压级要求的基础上,采用信号发射卡驱动水声换能器发声,然后通过数据采集卡采集换能器接收到的声波信号。同时,对几种典型声信号进行了常温湖水声波飞渡时间实验。实验结果表明,18～23kHz的扫频信号可作为合适的声源信号。这不仅为声学测温中的声源选择提供了指导,而且对水下短距离声波的延时测量也具有一定的参考价值。

In order to select appropriate sound source signal for enhancing measurement accuracy of the acoustic temperature detector for deep sea hydrothermal vents, in accordance with the acoustic characteristics of the hydrothermal vent, and on the basis of requirements of frequency range and sound level of signals in measuring procedures, by using signal transmitting module to energize marine acoustic transducer for generating sound, then collect the sound wave signal from transducer through data acquisition module. In addition, the flying time under normal tem- perature for several typical sound signals in lake water are studied with experiments. The result of experiment indicates that the frequency sweeping signal from 18 kHz to 23 kHz can be used as the appropriate sound source. It provides guidance to sound source selection for acoustic temperature measurement, and also can be consulted in short-distance time-delay measurement under water.