针对缝间应力干扰造成的段内各裂缝非均匀延伸问题,建立综合考虑应力干扰、流固耦合、多裂缝流量分配的分段多簇压裂裂缝动态延伸数值模型。基于建立的数值模型,研究了射孔孔眼摩阻、射孔簇间距、储集层岩石弹性模量、压裂液黏度对多条水力裂缝延伸形态的影响。模拟结果表明,考虑射孔孔眼摩阻时裂缝发育较为均衡;随着簇间距缩小、岩石弹性模量或压裂液黏度增大,应力干扰增大,导致部分裂缝缝宽变窄而减少进液,加剧了段内各裂缝的非均匀延伸。合理的孔眼摩阻能够有效促进多裂缝均匀延伸,为此提出了简便的射孔孔眼摩阻优化计算方法。通过估算压裂过程中缝间诱导应力值,定量计算出维持压裂段内裂缝均匀延伸所需的孔眼摩擦系数,并以此优选合理的射孔工程参数。采用射孔摩阻优化方法对1口水平井射孔参数进行计算,数值模拟结果及现场压裂效果显示,优化后的射孔参数能够有效维持各裂缝均衡发育。图7表2参20
赵金洲
,
陈曦宇
,
李勇明
,
付斌
,
许文俊
. 水平井分段多簇压裂模拟分析及射孔优化[J]. 石油勘探与开发, 2017
, 44(1)
: 117
-124
.
DOI: 10.11698/PED.2017.01.14
Aiming at analyzing the issues of non-uniform growths of multiple hydraulic fractures caused by stress shadowing, a numerical model considering elasto-hydrodynamic, stress interference and flow distribution into different fractures was built. Based on the model, the effects of perforation friction, perforation cluster spacing, Young modulus of rock and fracturing fluid viscosity on the growth of multiple fractures were investigated. The simulation results show that the growths of hydraulic fractures are relatively uniform with adequate perforation friction; the reduction of perforation cluster spacing, increase of Young modulus or fluid viscosity will cause the reduction of some fracture width and uneven flow distribution into these fractures, thus aggravating non-uniform growth of multiple fractures. Since appropriate perforation friction is conducive to the uniform growth of fractures, a convenient quantitative optimization method to calculate the needed perforation friction for uniform growth was proposed. By estimating interfracture induced stress during fracturing, the perforation friction coefficient needed to maintain uniform growth of fractures inside a stage is calculated, and reasonable engineering parameters of perforation can be selected based on this. The perforation parameters of a horizontal well were calculated with the proposed method, and the simulation results and actual fracturing performance show that the optimized perforation parameters can effectively keep uniform growth of fractures.
[1] 邹才能, 翟光明, 张光亚, 等. 全球常规-非常规油气形成分布、资源潜力及趋势预测[J]. 石油勘探与开发, 2015, 42(1): 13-25.
ZOU Caineng, ZHAI Guangming, ZHANG Guangya, et al. Formation, distribution, potential and prediction of global conventional and unconventional hydrocarbon resources[J]. Petroleum Exploration and Development, 2015, 42(1): 13-25.
[2] 王永辉, 卢拥军, 李永平, 等. 非常规储层压裂改造技术进展及应用[J]. 石油学报, 2012, 33(1): 149-158.
WANG Yonghui, LU Yongjun, LI Yongping, et al. Progress and application of hydraulic fracturing technology in unconventional reservoir[J]. Acta Petrolei Sinica, 2012, 33(1): 149-158.
[3] MILLER C K, GEORGE A W, ERIK I R. Evaluation of production log data from horizontal wells drilled in organic shales[R]. SPE 144326-MS, 2011.
[4] OLSON J E. Multi-fracture propagation modeling: Applications to hydraulic fracturing in shales and tight gas sands[R]. ARMA-08-327, 2008.
[5] NAGEL N B, MARISELA S. Stress shadowing and microseismic events: A numerical evaluation[R]. SPE 147363-MS, 2011.
[6] ROUSSEL N P, MUKUL M S. Optimizing fracture spacing and sequencing in horizontal-well fracturing[J]. SPE Production & Operations, 2011, 26(2): 173-184.
[7] 赵金洲, 陈曦宇, 刘长宇, 等. 水平井分段多簇压裂缝间干扰影响分析[J]. 天然气地球科学, 2015, 26(3): 533-538.
ZHAO Jinzhou, CHEN Xiyu, LIU Changyu, et al. The analysis of crack interaction in multi-stage horizontal fracturing[J]. Natural Gas Geoscience, 2015, 26(3): 533-538.
[8] BUNGER A P, PEIRCE A P. Numerical simulation of simultaneous growth of multiple interacting hydraulic fractures from horizontal wells[C]//Shale Energy Engineering Conference 2014. Pittsburgh: American Society of Civil Engineers, 2014.
[9] PEIRCE A P, BUNGER A P. Interference fracturing: Nonuniform distributions of perforation clusters that promote simultaneous growth of multiple hydraulic fractures[J]. SPE Journal, 2015, 20(2): 384-395.
[10] WU Kan, OLSON J, MATTHEW T, et al. Numerical analysis for promoting uniform development of simultaneous multiple fracture propagation in horizontal wells[R]. SPE 174869-MS, 2015.
[11] LECAMPION B, DESROCHES J. Simultaneous initiation and growth of multiple radial hydraulic fractures from a horizontal wellbore[J]. Journal of the Mechanics and Physics of Solids, 2015, 82(2): 235-258.
[12] 邹才能, 张国生, 杨智, 等. 非常规油气概念、特征、潜力及技术: 兼论非常规油气地质学[J]. 石油勘探与开发, 2013, 40(4): 385-399.
ZOU Caineng, ZHANG Gousheng, YANG Zhi, et al. Geological concepts, characteristics, resource potential and key techniques of unconventional hydrocarbon: On unconventional petroleum geology[J]. Petroleum Exploration and Development, 2013, 40(4): 385-399.
[13] BUNGER A P, ZHANG X, ROBERT G J. Parameters affecting the interaction among closely spaced hydraulic fractures[J]. SPE Journal, 2012, 17(1): 292-306.
[14] CROUCH S L, STARFIELD A M. Boundary element methods in solid mechanics: With applications in rock mechanics and geological engineering[M]. New South Wales: Allen & Unwin, 1982.
[15] OLSON J E. Predicting fracture swarms: The influence of subcritical crack growth and the crack-tip process zone on joint spacing in rock[J]. Geological Society London Special Publications, 2004, 231(1): 73-88.
[16] DONTSOV E V, PEIRCE A P. An enhanced pseudo-3D model for hydraulic fracturing accounting for viscous height growth, non-local elasticity, and lateral toughness[J]. Engineering Fracture Mechanics, 2015, 142: 116-139.
[17] CRUMP J B, CONWAY M W. Effects of perforation-entry friction on bottomhole treating analysis[J]. Journal of Petroleum Technology, 1988, 40(8): 1041-1048.
[18] DONTSOV E V, PEIRCE A P. A non-singular integral equation formulation to analyse multiscale behaviour in semi-infinite hydraulic fractures[J]. Journal of Fluid Mechanics, 2015, 781(3): 248-254.
[19] PEIRCE A P, DETOURNAY E. An implicit level set method for modeling hydraulically driven fractures[J]. Computer Methods in Applied Mechanics and Engineering, 2008, 197(33): 2858-2885.
[20] ECONOMIDES M J, NOLTE K G. 油藏增产措施[M]. 3版. 北京: 石油工业出版社, 2002.
ECONOMIDES M J, NOLTE K G. Reservoir stimulation[M]. 3rd ed. Beijing: Petroleum Industry Press, 2002.
