过钻头正交偶极子声波测井换能器研究

项目名称： 过钻头正交偶极子声波测井换能器研究

项目编号： No.41474160

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 天文学、地球科学

项目作者： 丛健生

作者单位： 中国科学院声学研究所

项目金额： 90万元

中文摘要： 地层岩石属性分析与评价是制约我国长井段水平井页岩气开发中最佳水力压裂层段准确识别的技术瓶颈。目前，过钻头正交偶极声波测井技术是解决这一问题的首选测量方式，但其核心部件-换能器尚未攻克，主要问题是弯曲振子正交偶极声波换能器的微小体积与其低频、强发射能量之间的矛盾。因此，及早深入开展过钻头正交偶极声波换能器研究，具有重要的学术价值和较强的应用背景。 本申请在项目组已打破国外技术垄断、实现自主研发正交偶极声波换能器的基础上，结合过钻头测井技术特点，首先建立新型弯曲振子偶极声波换能器物理模型。其次，采用理论和数值分析方法对新模型进行仿真和优化设计。再次，对试制样件进行性能测试，并与理论结果对比，考察换能器材料、结构、边界条件等对振动模态、频响、阻抗、指向性、灵敏度的影响，分析影响换能器辐射能量的主控因素，并优化解决方案，为国际上尽早解决过钻头测井技术瓶颈问题提供一定的理论指导和强有力的实验数据。

中文关键词： 过钻头测井；正交偶极子；换能器；弯曲振子；水力压裂

英文摘要： Analysis and evaluation for Stratum rock properties are the bottleneck problems for correct identifying the best hydraulic cracking interval in a long horizontal well section in shale gas exploration and development in China. At present, Through Bit Cross Dipole Acousitc Logging (TBCDAL) is preferred to figure out this problem. However, the kernel component - transducer has not been conquerred. The main problem is the contradiction among small volume, low frequency and high emitting energy of TBCDAL transmitters. Therefore, early researching work on new models of TBCDAL transmitters shows important academic value and strong application background. This proposal is put forward on our preliminary basis of breaking the foreign technical monopoly and implementing the independent research and development of cross dipole acoustic logging transducers, and also combined characteristics of through bit logging (TBL) technology. Firstly, the new physical model of bender bar will be established. Secondly, the new model will be numerically simulated and optimally designed using the theoretical and numerical analysis methods. Thirdly, transducer samples will be made and their performances will be also measured. Further investigations will be concerned on the effects of materials, structure and boundary conditions on the vibrational modes, frequency response, impedance characteristics, directivity and sensitivity etc. Afterwards, the main factor influencing the emitting energy of transducers will be analyzed, and optimized solutions are obtained. The proposal above will provide theoretical references and forceful experimental data for early settling TBL bottleneck problems.

英文关键词： through bit logging;cross dipole;transducer;bender bar;hydraulic cracking