【作者】 张晓春；

【导师】 程远方；

【作者基本信息】 中国石油大学 ， 油气井工程， 2011， 硕士

【摘要】 从全球油气勘探开发的趋势来看,低渗透油气勘探开发的地位日益提升,已经成为全球开发的大趋势。爆炸动载压裂技术是一种潜在的开发低渗透油气田的新方法,爆炸压裂对井眼周围地层岩石的作用是一个十分复杂的过程。目前爆炸动载压裂的相关实验还很欠缺,为此,本文开展爆炸动载压裂室内模拟试验研究。本文为研究爆炸激波和爆生气体耦合作用下水泥试样损伤破坏规律,研制了一套爆炸动载压裂模拟试验装置。根据实验装置设计了试验方案,研究不同药量、不同围压以及不同材质等影响因素下,动载压裂的造缝效果和对水泥试样的损伤程度。在爆炸动载压裂试验的基础上,获得宏观裂缝分布图并用分形理论对试样表面裂缝分布特征和规律进行分析。研究结果表明:爆炸载荷作用下,水泥试样表面裂纹具有很好的分形特性,分形维数可作为试样损伤程度的描述参数;随着药量的增加、围压的减小,裂缝分形维数线性增长。建立了基于相对损伤度、裂缝孔隙度和渗透率来定量评价动载压裂后水泥试样损伤程度的方法。测量了爆炸动载作用前后岩心的弹性波速,并计算了试样弹性参数;测试了爆炸压裂后试样的裂缝孔隙度;测量了爆炸压裂前后岩心的渗透率。推导出相对损伤度、孔隙度和渗透率随药量、围压等的变化关系。建立了爆炸动载作用后水泥试样的相对损伤度模型,推导了实验条件下相对损伤度和渗透率之间的定量关系。根据爆炸压裂后裂缝条数较多、裂缝长度较短且井眼附近储层渗透率变化的特点,本文采用解析方法,推导了适合爆炸压裂井动态产能预测模型。根据以上分析结果,编制了压裂单井动态产能预测软件。在此基础上,研究了裂缝条数、裂缝长度对油井产量的影响规律。更多还原

【Abstract】 In the trend of petroleum exploitation, the position of low permeability reservoir has been rising. The exploitation of low permeability reservoir has become the global megatrends. Explosive fracturing is an potentially method in developing low permeability reservoir, and it effect the rock around the borehole with a complex process. The current experiment of explosive fracturing is still absent, so the laboratory experiment of explosive fracturing is studied in this thesis.The simulation test device of explosive fracturing is developed in this thesis, to research the rule of cement sample damage by blast wave and explosion gas. According to the experimental device the program is designed, to study the effect of explosive fracturing and the damage of cement sample by different explosive quantity, confining pressure and materials.On the base of explosive fracturing experiment, scattergram of macro-cracks is obtained and then distribution characteristics and rules of the sample surface cracks by fractal theory. The results of the study show that: the surface cracks of cement sample process fractal characteristics, and the fractal dimension can describe the damage of the sample as a parameter during explosive loading. As the explosive quantity increase and the confining pressure decrease, the fractal dimension of cracks increases linearly.Based on relative damage, fracture porosity and permeability, the quantitative evaluation method for the cement sample after exploding is established. The elastic wave velocity of core before and after explosion is measured, and the elastic parameter of sample is calculated; The fracture porosity of sample after explosion is gained; The permeability of core before and after explosion is measure. The variation of relative damage, porosity and permeability with explosive quantity and confining pressure is deduced. The relative damage model of cement sample after exploding is established, the quantitative relationship between relative damage and permeability is deduced under experiment condition.Based the feature of that crack number is more, crack length is shorter and the permeability around the borehole is different, the dynamic production forecasting formulas of explosion fracturing well is deduced in this thesis. According to the above analysis result, the dynamic production forecasting software of fracturing well is designed. On that basis, it is studied that the production of well was influenced by the number of cracks and the length of crack.更多还原