Research And Experimental Study On Acoustic Measuring Instrument Of Gas Seeping On Seafloor

Using acoustic research of the seafloor seepage has important significance in the field of marine resources development and ecological protection. The main acoustic parameters of seafloor seepage research include:sound velocity, sound attenuation and bubble velocity. The study of the seafloor seepage bubble sound characteristics is mainly using the methods of measuring echo ultrasound. The method of measuring echo ultrasound is difficult to ensure the measurement accuracy, because it is in a relatively open environment, which the echo signal could be impacted of the outside acoustic signal. So, the paper is based on the research of our group, which developed the system of continuous sine wave acoustic measurement and acoustic parameters data acquisition, studied on acoustic properties of bubble-water medium by the system of continuous sine wave acoustic measurement.The current seafloor seepage research situation of acoustic measurement was introduced, the acoustic measurement principle of seafloor seepage and the calculation method of acoustic propertie parameters were summarized. The development research of study on acoustic measurement of gas seeping on seafloor was reviewed, and then the acoustic waveform effect of measuring acoustic properties parameters was introduced, it is the reason why continuous sine wave acoustic measurement and the system of acoustic parameters data acquisition were designed.The hardware system of continuous sine wave acoustic measurement includes three parts:the generating circuit of ultrasonic signal, the circuit of power amplifying, the circuit of resonance matching. The circuit of ultrasonic generator and acoustic counting module were, designed in part of the generating circuit of ultrasonic signal. The circuit of power amplifying, which introduced the selection of power amplification circuit and switch device, as well as designed and debugged the circuit of power amplifier. The principle of transducer resonance matching was introduced, and then the circuit of resonance matching was designed. Finally, the hardware system of continuous sine wave acoustic measurement was debugged.Based on the system of continuous sine wave acoustic measurement, acoustic properties of the seafloor seepage bubble-water medium experiment was carried out. Analyzed the sound wave signals which wave collected by the measurement system, mainly included bubble-water sound velocity, sound attenuation. By the acoustic properties experiment of the seafloor seepage bubble-water medium demonstrated the validity of he system of continuous sine wave acoustic measurement.The system of acoustic parameters data acquisition was designed to fit the practical need of measuring. The program of VB and CPLD was compiled by the system of communication protocol and data interface. At last, through the system of acoustic parameters data acquisition was debugged, verified the feasibility of the design.The improving advices about the system of continuous sine wave acoustic measurement and acoustic parameters data acquisition were presented in the paper, combined with the problems of the processing of experimental data analysis and experiment measurement.