幂率型裂隙分布煤层渗流场与变形应力场耦合模型及数值模拟

doi:10.13722/j.cnki.jrme.2021.0696

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摘要煤体的微观结构对其产气量有着显著的影响，然而，现阶段的煤层气开采模型都未将此因素考虑在内。为了定量分析煤层微观结构对宏观渗流过程的影响，基于幂律分形渗透模型，构建一种能够同时考虑煤层微观结构与多物理场因素相互作用的裂隙–孔隙渗流模型。模型将多物理场效应(包括气体吸附–解吸效应、气体渗流诱导储层形变效应、煤层基质形变、裂隙–基质相互作用等)定义为储层有效应力的函数，进而作用于储层孔隙率与微观结构。分析煤体的主要结构参数对宏观渗透率的影响，包括：(1) 裂隙长度幂律指数a；(2) 裂隙长度最值比r；(3) 最大裂隙长度l，并分析煤层形变及渗透率的时空演化趋势。模拟结果表明：煤体结构参数对煤体渗透率有着显著的影响。当孔隙率等其他煤体参数保持不变时，储层宏观渗透率与裂隙长度最值比r、最大裂隙长度l成正比，与裂隙长度幂律指数成反比；此外，与裂隙长度幂律指数、裂隙长度最值比相比，煤层最大裂隙长度对煤层渗透率有着更为显著的影响。

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	刘冠男1
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	叶大羽1
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	高峰1
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	岳丰田1
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	高涛1
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关键词 ：采矿工程, 煤层结构, 分形几何, 煤层渗透率, 多场耦合模型, 吸附应力

Abstract：Coal microstructure has a significant impact on gas production. However，current coalbed methane (CBM) extraction models fail to consider this factor. In order to quantify the influence of the coal seam microstructure on macroscopic seepage processes，a fracture-matrix seepage model is developed based on the power-law fractal permeability theory，which is able to simultaneously analyze the interaction between the coal seam microstructure and multi-physical field factors. This model defines the multi-physical field effects(including gas adsorption- desorption effect，seepage-induced reservoir deformation，coal matrix deformation，fracture-matrix interactions，etc.) as functions of the effective stress in the reservoir，which in turn operate on the reservoir porosity and the microstructure. Furthermore，the influence of the main structural parameters of the coal seam on the macroscopic permeability，including general power law exponent a，extremum crack length ratio r and maximum fracture length l，is investigated，and the spatial and temporal evolutions of coal seam deformation and permeability are also analyzed. The simulation results show that the structural parameters of the coal seam have a significant influence on the permeability. The permeability of coal is proportional to the extremum fracture length ratio and the maximum fracture length while is inversely proportional to the general power law exponent. Moreover，the maximum fracture length of the coal seam has a more significant effect on the coal seam permeability than the general power law exponent and the extremum fracture length ratio.

Key words： mining engineering coal structure fractal geometry coal permeability multi-field coupling model adsorption stress

引用本文:

刘冠男1，2，3，叶大羽1，2，高峰1，2，3，岳丰田1，2，3，高涛1，2，3. 幂率型裂隙分布煤层渗流场与变形应力场耦合模型及数值模拟[J]. 岩石力学与工程学报, 2022, 41(3): 492-502.
LIU Guannan1，2，3，YE Dayu1，2，GAO Feng1，2，3，YUE Fengtian1，2，3，GAO Tao1，2，3 . Coupled model of seepage and deformation fields in power-law fracture-distributed coal seam. , 2022, 41(3): 492-502.

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http://rockmech.whrsm.ac.cn/CN/10.13722/j.cnki.jrme.2021.0696 或 http://rockmech.whrsm.ac.cn/CN/Y2022/V41/I3/492

[35]	PICKERING G，BULL J M，SANDERSON D J. Sampling power-law distributions[J]. Tectonophysics，1995，248(1)：1-20.
[3]	LIU G，YE D，GAO F，et al. A dual fractal poroelastic model for characterizing fluid flow in fractured coal masses[J]. Geofluids，2020，2020：1-13.
[20]	YU B，LI J. Some fractal characters of porous media[J]. Fractals，2001，9(3)：365-372.
[34]	YU B，LEE L，CAO H. A fractal in-plane permeability model for bi-dispersed porous media[J]. International Journal of Heat and Mass Transfer，2002，45： 2 983-2 993.
[7]	YE D，LIU G，GAO F，et al. A study on the structure of rock engineering coatings based on complex network theory[J]. Coatings，2020，10(12)：1 152.
[8]	YE D，LIU G，GAO F，et al. A fractal model of thermal- hydrological-mechanical interaction on coal seam[J]. International Journal of Thermal Sciences，2021，168(4)：107048.
[10]	PONE J D N，HILE M，HALLECK P M，et al. Three-dimensional carbon dioxide-induced strain distribution within a confined bituminous coal[J]. International Journal of Coal Geology，2009，77(1/2)：103-108.
[17]	YE D，LIU G，GAO F，et al. A multi-field coupling model of gas flow in fractured coal seam[J]. Advances in Geo-energy Research，2021，5(1)：104-118.
[18]	CAO P，LIU J，LEONG Y K. Combined impact of flow regimes and effective stress on the evolution of shale apparent permeability[J]. Journal of Unconventional Oil and Gas Resources，2016，14：32-43.
[38]	ANITA T，SILJE S. Scaling of fault attributes：A review[J]. Marine and Petroleum Geology，2011，28(8)：1 444-1 460.
[1]	朱斌，高峰，杨建文，等. 深部薄层煤岩体裂隙-孔隙双渗流模拟研究[J]. 中国矿业大学学报，2014，43(6)：987-994.(ZHU Bin，GAO Feng，YANG Jianwen，et al. Simulation research on fissure-porosity double percolation in deep-buried thin-layer coal rock mass [J]. Journal of China University of Mining and Technology，2014，43(6)：987-994.(in Chinese))
[4]	沈珊，卢双舫，唐明明，等. 致密砂岩储层微观孔喉表征及渗流模拟[J]. 河南科学，2016，34(10)：1 699-1 705.(SHEN Shan，LU Shuangfang，TANG Mingming，et al. Micro pore throat characterization and seepage stimulation of tight sandstone reservoir[J]. Henan Science，2016，34(10)：1 699-1 705.(in Chinese))
[6]	LIU G，LIU L，LIU J，et al. A fractal approach to fully-couple coal deformation and gas flow[J]. Fuel，2019，240(MAR.15)：219-236.
[9]	WANG H，SHI R，DENG D，et al. Characteristic of stress evolution on fault surface and coal bursts mechanism during the extraction of longwall face in Yima mining area，China[J]. Journal of Structural Geology，2020，136：104071.
[11]	LIU R，JIANG Y，LI B，et al. A fractal model for characterizing fluid flow in fractured rock masses based on randomly distributed rock fracture networks[J]. Computers and Geotechnics，2015，65：45-55.
[14]	CUI X，BUSTIN R M. Volumetric strain associated with methane desorption and its impact on coalbed gas production from deep coal seams[J]. Aapg Bulletin，2005，89(9)：1 181-1 202.
[16]	AU P I，LIU J，LEONG Y K. Yield stress and microstructure of washed oxide suspensions at the isoelectric point：experimental and model fractal structure[J]. Rheologica Acta，2016，55(10)：847-856.
[19]	DREUZY J R，DAVY P，BOUR O. Hydraulic properties of two-dimensional random fracture networks following a power law length distribution：2. Permeability of networks based on lognormal distribution of apertures[J]. Water Resources Research，2001，37(8)：2 079-2 096.
[21]	ZHANG H，LIU J，ELSWORTH D. How sorption-induced matrix deformation affects gas flow in coal seams：A new FE model[J]. International Journal of Rock Mechanics and Mining Sciences，2008，45(8)：1 226-1 236.
[24]	柴军瑞. 采用Monte-Carlo模拟技术计算裂隙岩体的分维数[J]. 水文地质工程地质，2000，27(2)：12-13.(CHAI Junrui. Statistic analysis of the fractal dimension of fractured rock by Monte-Carlo analogy technique[J]. Hydrogeology and Engineering Geology，2000，27(2)：12-13.(in Chinese))
[26]	RAEINI A Q，BIJELJIC B，BLUNT M J. Generalized network modeling：Network extraction as a coarse-scale discretization of the void space of porous media[J]. Physical Review E.，2017，96(1)：013312.
[2]	张彦洪，柴军瑞. 考虑渗流特性的岩体结构面分形特性研究[J]. 岩石力学与工程学报，2009，28(增2)：3 423-3 429.(ZHANG Yanhong，CHAI Junrui. Study on fractal property of fractured rock mass considering seepage characteristics[J]. Chinese Journal of Rock Mechanics and Engineering，2009，28(Supp.2)：3 423-3 429.(in Chinese))
[12]	LIU Z，FENG Z，ZHANG Q，et al. Heat and deformation effects of coal during adsorption and desorption of carbon dioxide[J]. Journal of Natural Gas Science and Engineering，2015，25：242-252.
[22]	LIU G，YU B，YE D，et al. Study on evolution of fractal dimension for fractured coal seam under multi field coupling[J]. Fractals，2020，DOI：10.1142/S0218348X20500723
[29]	LIU G，YE D，YU B，et al. A study on gas drainage considering coupling process of fracture-pore microstructure and coal deformation[J]. Fractals，2021，29(2)：2150065
[31]	ROBERTSON E，CHRISTIANSEN R. Modeling permeability in coal using sorption-induced strain data[C]// Proceedings of 2005 SPE Annual Technical Conf. Exhibition. Dallas：[s. n.]，2005：97 068.
[32]	MIAO T，YU B，DUAN Y，et al. A fractal analysis of permeability for fractured rocks[J]. International Journal of Heat and Mass Transfer，2015，81(feb.)：75-80.
[36]	WATTERSON J，WALSH J J，GILLESPIE P A，et al. Scaling systematics of fault sizes on a large range fault map[J]. Journal of Structural Geology，1996，18(2)：199-214.
[39]	QINGHU X，DECHUN C，QIANG L，et al. Property and industry standard formulation of natural gas product made from coal[J]. Technology Supervision in Petroleum Industry，2016，32(8)：25-29.
[5]	柴军瑞. 考虑渗透动水压力时等效连续岩体渗流场与应力场耦合分析的数学模型[J]. 四川大学学报：工程科学版，2001，(6)：14-17. CHAI Junrui. Mathematical model for coupled seepage and stress fields in rock mass of equivalent continuum by considering hydrodynamic seepage pressure[J]. Journal of Sichuan University：Engineering Science，2001，(6)：14-17.(in Chinese))
[13]	CIVAN F，RAI C S，SONDERGELD C H. Shale-gas permeability and diffusivity inferred by improved formulation of relevant retention and transport mechanisms[J]. Transport in Porous Media，2011，86(3)：925-944.
[15]	CHAI J，LI S，WU Y. Multi-level fracture network model for coupled seepage and stress fields in rock mass[J]. Communications in Numerical Methods in Engineering，2004，20(1)：63-74.
[23]	MIAO T，CHENG S，CHEN A，et al. Seepage properties of rock fractures with power law length distributions[J]. Fractals，2019，27(4)：1950057.
[25]	PALMER I，MANSOORI J. How permeability depends on stress and pore pressure in coalbeds：a new model[J]. Spe Reservoir Evaluation and Engineering，1996，1(6)：539-544..
[27]	ZHANG H，LIU J，ELSWORTH D. How sorption-induced matrix deformation affects gas flow in coal seams：A new FE model[J]. International Journal of Rock Mechanics and Mining Sciences，2008，45(8)：1 226-1 236.
[28]	CHEN Z，LIU J，ELSWORTH D，et al. Impact of CO2 injection and differential deformation on CO2 injectivity under in-situ stress conditions[J]. International Journal of Coal Geology，2010，81(2)：97-108.
[30]	ZHANG S，LIU J，WEI M，et al. Coal permeability maps under the influence of multiple coupled processes[J]. International Journal of Coal Geology，2018，187(1)：71-82.
[33]	YANG S，YU B，ZOU M，et al. A fractal analysis of laminar flow resistance in roughened microchannels[J]. International Journal of Heat and Mass Transfer，2014，77(1)：208-217.
[37]	ODLING N，GILLESPIE P，BOURGINE B，et al. Variations in fracture system geometry and their implications for fluid flow in fractures hydrocarbon reservoirs[J]. Petroleum Geoscience，1999，5(4)：373-384.
[40]	MITRA A，HARPALANI S，LIU S. Laboratory measurement and modeling of coal permeability with continued methane production：Part 1—Laboratory results[J]. Fuel，2012，94：110-116.