冷泉渗漏声波测量装置主体研制与气泡—水声学特性的实验研究

发布时间：2018-06-04 13:36

本文选题：海底冷泉渗漏 + 声特性　；参考：《广东工业大学》2014年硕士论文

【摘要】：海底冷泉渗漏气泡-水介质声学特性的研究在经济建设与生态保护等领域均具有重要的意义。海底冷泉渗漏气泡-水介质主要的声学物理特性参数包括：声速、声衰减和气泡流速。目前海底冷泉渗漏气泡流量可以采用超声回波测量,由于开放环境下气泡的流动状态不稳定,反向超声回波不但经历了海水的衰减,而且受到随机分布气泡的前向与逆向散射,回波信号是一种不稳定的信号,造成测量精度难以保证。因此,为满足海底冷泉渗漏流量研究的需要,在本课题组前期研究的基础上,本文模拟海底冷泉渗漏,研制了以气泡破碎均匀装置为预处理模块、矩形换能器为传感器的海底冷泉渗漏声波测量装置,采用透射声波波形-幅度测量气泡流量。论文介绍了海底冷泉渗漏气泡测量的研究现状,包括非声波测量法与声波测量法。概述了海底冷泉渗漏气泡主要的声特性。针对本实验测量原理,分析了气泡-水介质的声速、声衰减和气泡流速的计算方法。阐述了海底冷泉渗漏声波测量装置的总体设计和结构设计的两部分：气泡收集与预处理装置和传感器测量装置。气泡收集与预处理装置主要介绍了气泡破碎网格与气泡破碎均匀装置,并对其结构及工作原理作了介绍。传感器测量装置主要介绍了发射换能器模块和矩形换能器。对测量装置的关键部件—声波分路器进行了详细设计与实验验证,通过在空气中与水中的实验验证了声波分路器设计的合理性与有效性。通过发射与接收换能器模块的耦合接触,求出测量系统的传播时间。运用设计的声学特性测量系统,以1MHz的矩形换能器为传感器,模拟海底冷泉渗漏气泡-声波特性测量实验。对采集到的声波信号进行分析处理,主要包括气泡-水介质的声速、声衰减和气泡流速。研究不同容积含气率声特性参数的变化情况。研究不同水深对实验测量结果的影响,对比分析了不同水深下,气泡-水介质的声速、声衰减和气泡流速的变化情况。根据系统调试与实验测量中发现的问题,提出海底冷泉渗漏气泡-声波特性测量需进一步改进意见。
[Abstract]:The study of acoustic characteristics of percolation bubble-water medium in cold spring is of great significance in the fields of economic construction and ecological protection. The main acoustic physical parameters of the percolation bubble-water medium include sound velocity sound attenuation and bubble velocity. At present, the leakage bubble flow of cold spring can be measured by ultrasonic echo. Due to the instability of bubble flow in open environment, the reverse-ultrasonic echo not only undergoes the attenuation of seawater, but also is subjected to the forward and reverse scattering of randomly distributed bubbles. Echo signal is a kind of unstable signal, which makes the precision of measurement difficult to guarantee. Therefore, in order to meet the need of the research on the leakage flow of submarine cold spring, based on the previous research of our group, this paper simulates the leakage of cold spring on the sea floor, and develops a preprocessing module based on the uniform device of bubble breakage. The rectangular transducer is a sensor for measuring the acoustic leakage of the cold spring at the bottom of the sea. The acoustic wave waveforms and amplitude are used to measure the flow rate of the bubble. In this paper, the research status of bubble leakage measurement in cold spring is introduced, including non-acoustic wave measurement and acoustic wave measurement. In this paper, the main acoustic characteristics of leakage bubbles in submarine cold springs are summarized. According to the principle of this experiment, the calculation methods of sound velocity, sound attenuation and bubble velocity of bubble-water medium are analyzed. In this paper, the general design and structure design of the acoustic wave measuring device for cold spring leakage in submarine are described: the bubble collecting and preprocessing device and the sensor measuring device. Bubble collecting and preprocessing device mainly introduces bubble breaking mesh and bubble breaking uniform device, and introduces its structure and working principle. Sensor measuring device mainly introduces the transmitter module and rectangular transducer. The design and experimental verification of the acoustic splitter, the key component of the measuring device, are carried out in detail. The rationality and validity of the design of the acoustic splitter are verified by experiments in air and water. The transmission time of the measurement system is calculated by the coupling contact between the transmitter and the receiving transducer module. Using the designed acoustic characteristic measurement system and using the rectangular transducer of 1MHz as the sensor, the experiment of measuring the bubble and acoustic wave characteristics of the cold spring leakage in the seafloor is simulated. The acoustic signals collected are analyzed and processed, including the sound velocity, sound attenuation and bubble velocity of the bubble-water medium. The change of acoustic characteristic parameters of different volume gas holdup was studied. The effects of different water depths on the experimental results are studied. The variation of sound velocity, sound attenuation and bubble velocity in bubble water medium under different water depths are compared and analyzed. According to the problems found in the system debugging and experimental measurement, it is suggested that the measurement of bubble-acoustic characteristics of submarine cold spring leakage should be further improved.
【学位授予单位】：广东工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：P716.4

【引证文献】