中南大学学报（自然科学版）2017，Vol.48Issue(7)：1866-1874,9.DOI:10.11817/j.issn.1672-7207.2017.07.025
煤岩脉动水力压裂过程中声发射特征的试验研究
Experimental study on acoustic emission characteristics in coal seam pulse hydraulic fracturing
摘要
Abstract
Experiments on acoustic emission characteristics of the process of pulse hydraulic fracturing at different pulse frequencies and different fracturing fluid viscosities were carried out by the true tri-axial pulse hydraulic fracturing test system and the PAC AE instrument.The acoustic emission behavior evolution characteristics,the damage evolutionary rule and the dynamic feature of b were analyzed.The results show that the evolution of acoustic emission behavior stimulated by pulse hydraulic fracturing in coal bed can be divided into four phases with time,including gentle period,acceleration period,boosting period and steady period.The accumulated average energy of acceleration period and boosting period increases respectively by 40.9 and 52.7 times compared with those of the gentle period.The damage evolution process can be divided into three phases,including initial damage period,damage development period and damage accelerating development period,and AE information can fairly reflect the damage evolution character of coal.Besides,a lower frequency corresponds to stronger AE energy release and higher fracture growth level,higher fracturing fluid viscosity corresponds to a smoother AE energy release and relatively lower fracture growth level,and also the variation of AE amplitude distribution is larger,b is greater and proportion of larger AE events is smaller when the frequency or the fracturing fluid viscosity is lower during the fracturing process.关键词
煤岩/脉动水力压裂/脉冲频率/压裂液黏度/声发射Key words
coal bed/pulse hydraulic fracturing/pulse frequency/fracturing fluid viscosity/acoustic emission (AE)分类
能源科技引用本文复制引用
吴晶晶,张绍和,孙平贺,曹函,陈江湛..煤岩脉动水力压裂过程中声发射特征的试验研究[J].中南大学学报（自然科学版）,2017,48(7):1866-1874,9.基金项目
国家自然科学基金资助项目(41302124) （41302124）
湖南科技大学页岩气资源利用湖南省重点实验室开放基金资助项目(E21425) （E21425）
中南大学中央高校基本科研业务费专项资金资助项目(2015zzts066) (Project(41302124) supported by the National Natural Science Foundation of China （2015zzts066）
Project(E21425) supported by the Hunan Provincial Key Laboratory of Shale Gas Resource Utilization of Hunan University of Science and Technology （E21425）
Project(2015zzts066) supported by the Fundamental Research Funds for the Central Universities of Central South University) （2015zzts066）
