摘要
连续油管内压裂液沿程摩阻压降是现场压裂施工设计的一个重要方面,同时也是压裂作业成功与否的关键因素之一。现场压裂液摩阻计算时,通常采用经验方法或相关计算软件进行分析,由于压裂液不同流体类型等因素限制,因此有必要针对连续油管压裂工作液的沿程摩阻进行分析,特别是支撑剂对流体压降的影响规律研究。在调研前人对该领域研究成果的基础上,对23/8in连续油管内前置液、携砂液、顶替液的流动压耗进行了实例分析,并对影响连续油管内压裂液摩阻压降的影响因素,如流体流变性、管径、支撑剂体积分数等进行敏感性分析。分析结果表明:幂律型压裂液,随着稠度系数的增加,压裂液的摩阻压降梯度对流变指数越来越敏感;管径是影响压裂液压降梯度较大,随着管径减小,其效果越显著;随着石英砂体积分数增加,携砂液压将系数和压降梯度呈现先增加后减少的变化规律,其分界点为体积分数30%。
Friction pressure drop of fracturing fluid was an important aspect in the design of fracturing operation,it was also the key factor of success or not in fracturing operations.Friction pressure drop of fracturing fluid was usually calculated by empirical methods or relevant calculation software,due to the limitation of fracturing fluid types and other factors,it was necessary to analyze the fracturing fluid friction pressure drop in the coiled tubing,especially the influence of fracturing proppant.Based on the research of predecessors' research achievements in this field,a case study was carried out on pressure loss of prepad fluid,sand-carrying fluid and displacement fluid in the 23/8in coiled tubing,and the sensitivity of influential factors of friction pressure drop in the fracturing fluid was analyzed,such as fluid rheology,pipe diameter,and volumetric fraction of the proppant.The analysis results show that the friction pressure gradient of fracturing fluid is sensitive to the rheological index with the increasing of consistency coefficient of fracturing fluid,the influence of coiled tubing diameter is obvious on the fracturing pressure gradient,with the decreasing of its diameter.The pressure drop coefficient and pressure gradient are first raised and then reduced with increasing of the volumetric fraction of quartz sand,and the cut-off point is in the volumetric fraction of 30%.
出处
《长江大学学报（自科版）（中旬）》
2016年第4期60-64,5-6,共5页
Journal of Yangtze University(Nature Science Edition)
关键词
连续油管
压裂液
压降分析
敏感性因素
coiled tubing
fracturing fluid
pressure-drop analysis
sensible factor
