Production analysis and optimal design of explosive fracturing technology for low permeability reservoir
-
摘要: 基于爆炸压裂裂缝分布规律,提出爆炸压裂缝网双重介质复合流动产能模型,应用Laplace变换Stehfest数值反演,得到了定压条件下封闭外边界低渗透油藏爆炸压裂生产井产能表达式。在模型正确性验证的基础上结合某低渗透油藏储层特征参数研究了爆炸压裂改造区域参数对封闭边界油藏产量的影响,同时对爆炸压裂改造改造体积优化设计进行了研究。研究结果表明,爆炸压裂改造区域半径主要影响生产中期产能,改造区域渗透率对生产早期和中期影响比较大,且对于实例油藏爆炸压裂改造比为0.1时效果最好。Abstract: The explosive fracturing technique is often adopted to produce and expand fractures due to its great shock waves, thus improving the low permeability of oil reservoirs. Based on the distribution characteristics of the explosive fracturing network and applying the Laplace transform and the Stehfest numerical inversion, this paper presents a new analytic mathematical production model for the complex-flow to an explosive fracturing well and obtains the formulas for the oil output under the constant pressure in different boundary conditions. On the basis of the model validation, this paper investigates the influence of the fracture network parameters on the output and the optimal design of the explosive fracturing. It is shown that the permeability of the fracture network exerts a great influence on the production. In addition, this paper offers an optimal design for explosive fracturing. The results from this study are expected to be significantly helpful for the optimal design of explosive fracturing and provide a rational design about the explosive quantity in low permeable reservoirs.
-
区别于一般的爆炸力学和冲击动力学计算,毁伤仿真计算往往需要对完整目标场景甚至阵地场景进行武器打击全过程计算,同时又需要近实时给出计算结果。这种大场景和快速计算在武器研发和运用的工程实际中有着强烈的应用需求。现有爆炸和冲击动力学计算方法(如FEM)由于计算规模和计算效率的限制,在进行毁伤场景计算时往往只能对目标构件或者局部区域进行计算,很难满足毁伤仿真的应用需求。近年来出现了一些快速算法,如镜像爆源法、侵彻微分面元法和破片射线追踪法等,这些快速算法充分利用解析公式、经验数据或代理模型,结合计算机仿真与可视化技术,形成实用工具,有力支撑了国防工业和军事领域的应用。
毁伤快速算法的求解时间必须满足强制时间约束条件,在优先满足时间效率要求的前提下,综合采用解析公式、经验数据、数值计算、人工智能、计算机仿真等方法,进行算法创新和集成应用。毁伤快速算法是一种既区别于解析公式法,又区别于传统有限元的求解方法,既有解析公式稳健可靠的特性,又有有限元方法良好的复杂几何形状适用性,填补了解析公式和有限元方法之间巨大的方法空白。这类方法能够抓住毁伤的主要特征进行快速求解,其特点主要包括:复杂三维场景适用,时间差分推进,数据驱动为主、模型驱动为辅,“绝对的时效性、相对的准确性”,物理毁伤、功能毁伤和任务毁伤的一体化计算等。毁伤仿真是一个典型的多学科交叉、多技术融合的领域,尤其对于计算机图形学等计算机仿真学科和相关技术有很强的依赖性,典型例子就是射线追踪法(ray tracing)在破片场求解中的应用。此外,在实际应用中,对于软件友好操作、三维可视化等功能也有很强的技术需求,可以说毁伤快速算法和计算机仿真技术构成了深度耦合的关系。
根据工作需要,我国不少科研单位开展了一些相关基础研究,并形成了相应的研究成果,但是针对这一领域进行系统学术交流的平台一直缺乏。为了推动毁伤快速算法和仿真技术领域的科学发展,促进此类方法在国防安全领域的运用,2023年7月,在中国力学学会爆炸力学分会计算爆炸力学专业组的指导下,国防科技大学理学院和湖南大学土木工程学院联合承办了2023年毁伤快速算法与仿真技术研讨会,旨在探讨毁伤快速算法和仿真技术的关键技术和发展方向。我国本领域专家学者积极参会和投稿,贡献出了精彩的学术报告和高质量的学术论文,会议规模远超组委会的预期。经过《爆炸与冲击》期刊的严格审稿流程,多篇文章有幸获得发表,形成本期专题。会议组委会由衷感谢全部参会人员、论文作者和审稿专家,特别感谢《爆炸与冲击》编辑部为本专题出版做出的贡献!
国防科技大学 卢芳云 教授
-
-
[1] 王凤琴, 廖红伟, 蒋峰华, 等.低渗油田注水能力下降原因分析及其对策研究[J].西安石油大学学报:自然科学版, 2009, 24(1):52-55. http://d.old.wanfangdata.com.cn/Periodical/xasyxyxb200901013Wang Fengqin, Liao Hongwei, Jiang Fenghua, et al.Causes and counter measures for the descend of the water injection capacity of low permeability reservoirs[J]. Journal of Xi'an Shiyou University: Natural Science Edition, 2009, 24(1):52-55. http://d.old.wanfangdata.com.cn/Periodical/xasyxyxb200901013 [2] 黄荣樽.水力压裂裂缝的起裂和扩展[J].石油勘探与开发, 1981, 8(5):62-74. http://d.old.wanfangdata.com.cn/Periodical/sydxxb200805018Huang Rongzun. Crack hydraulic fracturing cracks and the extension[J]. Petroleum Exploration and Development, 1981, 8(5):62-74. http://d.old.wanfangdata.com.cn/Periodical/sydxxb200805018 [3] 傅尤校.水力压裂裂缝的延伸与储层的连续性[J].石油学报, 1984, 5(2):55-62. http://www.cnki.com.cn/Article/CJFDTotal-SYXB198402009.htmFu Youxiao. Extension of fractures created by hydraurrac and continuity of reservoir[J]. Acta Petrolei Sinica, 1984, 5(2):55-62. http://www.cnki.com.cn/Article/CJFDTotal-SYXB198402009.htm [4] Yew C H. Mechanics of hydraulic fracturing[J]. Developments in Petroleum Science, 1997, 210(07):369-390. http://d.old.wanfangdata.com.cn/Periodical/mtxb201408041 [5] Britt L K. Optimization oil well fractures of mode rate permeability reservoir[C]//SPE Annual Technical Conference and Exhibition. Las Vegas, Nevada, 1985. https://www.onepetro.org/conference-paper/SPE-14371-MS [6] Shlyapobersky J K, Chudnovsky A K. Fracture mechanics in hydraulic fracturing[C]//US Symposium on Rock Mechanics. 1992. [7] Jeffrey R G, Zhang Xi. Mechanics of Hydraulic Fracture Growth From a Borehole[C]//Canadian Unconventional Resources and International Petroleum Conference. Calgary, Alberta, Canada, 2010. https://www.onepetro.org/conference-paper/SPE-137393-MS [8] 徐鹏, 程远方, 张晓春, 等.水泥试样爆炸压裂实验及裂纹分形评价[J].爆炸与冲击, 2011, 31(2):179-184. doi: 10.11883/1001-1455(2011)02-0179-06Xu Peng, Cheng Yuanfang, Zhang Xiaochun, et al. Fractal evaluation of explosive fracturing simulation test on cement samples[J]. Explosion and Shock Waves, 2011, 31(2):179-184. doi: 10.11883/1001-1455(2011)02-0179-06 [9] 赵志红, 郭建春.层内爆炸压裂技术原理及分析[J].石油天然气学报, 2008, 30(2):297-299. http://www.cnki.com.cn/Article/CJFDTOTAL-JHSX200802081.htmZhao Zhihong, Guo Jianchun. Experimental study on plug removal technology with self-excited oscillation[J]. Journal of Oil and Gas Technology, 2008, 30(2):297-299. http://www.cnki.com.cn/Article/CJFDTOTAL-JHSX200802081.htm [10] 程远方, 寇永强, 徐鹏, 等.水泥试样爆炸压裂模拟试验[J].中国石油大学学报:自然科学版, 2010, 34(5):69-72. http://d.old.wanfangdata.com.cn/Periodical/sydxxb201005012Cheng Yuanfang, Kou Yongqiang, Xu Peng, et al. Explosive fracturing simulation test of cement samples[J]. Journal of China University of Petroleum: Edition of Natural Science, 2010, 34(5):69-72. http://d.old.wanfangdata.com.cn/Periodical/sydxxb201005012 [11] 谢贤东.爆炸压裂后储层裂缝的渗流机理研究[D].北京: 中国石油大学, 2009. http://cdmd.cnki.com.cn/Article/CDMD-10425-2009222469.htm [12] 徐鹏, 程远方, 刘新云, 等.低渗透油气藏爆炸压裂模拟试验及裂缝分形特征[J].石油勘探与开发, 2013, 40(5):636-670. http://d.old.wanfangdata.com.cn/Periodical/syktykf201305021Xu Peng, Cheng Yuanfang, Liu Xinyun, et al. Explosive fracturing simulation experiment for low permeability reservoirs and fractal characteristics of cracks produced by explosive fracturing[J]. Petroleum Exploration and Development, 2013, 40(5):636-670. http://d.old.wanfangdata.com.cn/Periodical/syktykf201305021 [13] Grady D E, Kipp M E, Smith C S. Explosive fracture studies on oil shale[J]. Society of Petroleum Engineers Journal, 1980, 20(5):349-356. doi: 10.2118/8215-PA [14] Cui Mingyue, Shan Wenwen, Liang Jin, et al. In fracture explosive hydraulic fracturing fluid and its rhelogical study[C]//International Oil & Gas Conference and Exhibition in China. 2006. https://www.onepetro.org/conference-paper/SPE-103807-MS [15] Brown M L, Ozkan E, Raghavan R S, et al. Practical solutions for pressure transient responses of fractured horizontal wells in unconvertional reservoirs[J]. SPE Reservoir Evaluation & Engineering, 2009, 14(6):663-676. https://www.onepetro.org/journal-paper/SPE-125043-PA [16] Everdingen A F V, Hurst W. The application of the Laplace transformation to flow problems in reservoirs[J]. Journal of Petroleum Technology, 1949, 1(12):305-324. doi: 10.2118/949305-G [17] 孔祥言.高等渗流力学[M].合肥:中国科学技术大学出版社, 1999. -