Gas-water Two-phase Flow Simulation of Low-permeability Sandstone Digital Rock: Level-set Method

doi:10.19596/j.cnki.1001-246x.8322

Abstract

Abstract:

The pore throat structure of low permeability tight sandstone gas reservoir is complex. It is difficult to characterize the flow and distribution of gas and water in it. Based on real low-permeability sandstone core, micro-CT scanning technology was used to construct three-dimensional digital core of the reservoir. Connected pore structure was extracted and unstructured tetrahedral mesh model was established. With level-set method and N-S equation, a mathematical model of gas-water two-phase flow is established which is solved by finite element method. Water drive gas process, residual gas distribution, influence of rock wettability on two-phase flow in low-permeability sandstone gas-water two-phase flow, and interflow characteristics in parallel channels are studied. It shows that level-set method provides clearly gas-water two-phase distribution and migration of the displacement front. Rock wettability has great influence on two-phase flow process, and production degree is higher under water-wet conditions. Interflow phenomenon is obvious in parallel channels. Water phase in the large channel breaks through first and forms a dominant flow channel, while flow in the narrow channel is affected by capillary phenomenon and has great additional resistance.

Key words: low permeability sandstone, digital rock, level-set method, two phase flow, wettability

CLC Number:

TE312

Yulong ZHAO, Houjie ZHOU, Hongxi LI, Tao WEN, Ruihan ZHANG, Liehui ZHANG. Gas-water Two-phase Flow Simulation of Low-permeability Sandstone Digital Rock: Level-set Method[J]. Chinese Journal of Computational Physics, 2021, 38(5): 585-594.

Figures/Tables 9

Fig.1 (a)Gray image of low permeability sandstone; (b)Image obtained with non-local-means filter; (c)Pore segmentation results(xy plane); (d)Connected pore space; (e)Representative elementary volume; (f)Unstructured tetrahedral mesh; (g)Inlet; (h)Outlet

Fig.2 Two-phase flow simulation results

Fig.3 Shape of the displacement front in the displacement process (a)convex displacement front (s=5);(b)concave displacement front (s=13)

Fig.4 Two distributions of residual gas

Fig.5 Saturation over time

Fig.6 Simulation of water drive gas process at different wetting angles (a) θw=30°; (b) θw=60°; (c) θw=90°; (d) θw=120°

Fig.7 Relation of recovery degree and displacement time under different wetting conditions

Fig.8 (a)Grid division of parallel model; (b)Inlet(purple face); (c)Outlet(purple face)

Fig.9 Process of displacing in parallel channels

References 34

1	李闽, 蒋琼, 廖志, 等. 水驱气藏采收率计算方法及其影响因素研究[J]. 非常规油气, 2015, 2 (1): 35- 40. DOI
2	LEI Q, ZHANG L H, TANG H M, et al. Describing the full pore size distribution of tight sandstone and analyzing the impact of clay type on pore size distribution[J]. Geofluids, 2020, (3): 1- 20.
3	YANG Y, YANG H, TAO L, et al. Microscopic determination of remaining oil distribution in sandstones with different permeability scales using computed tomography scanning[J]. Journal of Energy Resources Technology, 2019, 141 (9): 092903. DOI
4	YANG Y, YAO J, WANG C, et al. New pore space characterization method of shale matrix formation by considering organic and inorganic pores[J]. Journal of Natural Gas Science and Engineering, 2015, 27, 496- 503. DOI
5	LI K, KONG S, XIA P, et al. Microstructural characterisation of organic matter pores in coal-measure shale[J]. Advances in Geo-Energy Research, 2020, 4 (4): 372- 391. DOI
6	SUN S, ZHANG T. A 6M digital twin for modeling and simulation in subsurface reservoirs[J]. Advances in Geo-Energy Research, 2020, 4 (4): 349- 351. DOI
7	LIU Z, YANG Y, YAO J, et al. Pore-scale remaining oil distribution under different pore volume water injection based on CT technology[J]. Advances in Geo-Energy Research, 2017, 1 (3): 171- 181. DOI
8	WANG H, YUAN X, LIANG H, et al. A brief review of the phase-field-based lattice Boltzmann method for multiphase flows[J]. Capillarity, 2019, 2 (3): 33- 52. DOI
9	YANG Y F, WANG K, ZHANG L, et al. Pore-scale simulation of shale oil flow based on pore network model[J]. Fuel, 2019, 251, 683- 692. DOI
10	AN S Y, YAO J, YANG Y F, et al. Influence of pore structure parameters on flow characteristics based on a digital rock and the pore network model[J]. Journal of Natural Gas Science and Engineering, 2016, 31, 156- 163. DOI
11	LI J H, ZHENG B. Digital core and pore network model reconstruction based on random fractal theory[J]. International Journal of Energy and Statistics, 2015, 3 (1): 1550001. DOI
12	HUANG X, BANDILLA K W, CELIA M A. Multi-physics pore-network modeling of two-phase shale matrix flows[J]. Transport in Porous Media, 2016, 111 (1): 123- 141. DOI
13	赵玉龙, 刘香禺, 张烈辉, 等. 致密砂岩气藏气水流动规律及储层干化作用机理[J]. 天然气工业, 2020, 40 (9): 70- 79.
14	ZHANG L, KANG Q J, YAO J, et al. Pore scale simulation of liquid and gas two-phase flow based on digital core technology[J]. Science China: Technological Sciences, 2015, 58 (8): 1375- 1384. DOI
15	ZAKIROV T, GALEEV A, KHRAMCHENKOV M. Drainage and impregnation capillary pressure curves calculated by the X-ray CT model of berea sandstone using lattice Boltzmann's method[J]. Earth and Environmental Science, 2017, 155, 19- 23.
16	ZHANG N, YAO J, HUANG Z Q, et al. Locally conservative Galerkin numerical simulation for two-phase flow in porous media[J]. Chinese Journal of Computational Physics, 2013, 30 (5): 667- 674.
17	高亚军, 姜汉桥, 王硕亮, 等. 基于Level Set有限元方法的微观水驱油数值模拟[J]. 石油地质与工程, 2016, 30 (5): 91- 142. 91-96, 141-142 DOI
18	ZHU Q L, ZHOU Q L, LI X C. Numerical simulation of displacement characteristics of CO₂ injected in pore-scale porous media[J]. Journal of Rock Mechanics and Geotechnical Engi-neering, 2016, 8 (1): 87- 92. DOI
19	AMIRI H A A, HAMOUDA A A. Pore-scale modeling of non-isothermal two phase flow in 2D porous media: Influences of viscosity, capillarity, wettability and heterogeneity[J]. International Journal of Multiphase Flow, 2014, 61, 14- 27. DOI
20	FENG Q H, ZHAO Y C, WANG S, et al. Pore-scale oil-water two-phase flow simulation based on phase field method[J]. Chinese Journal of Computational Physics, 2020, 37 (4): 439- 447.
21	GAO Y J, YANG R L, HUANG L L, et al. Phase field crystal simulation in nano-scale for crack extension with predeformation[J]. Chinese Journal of Computation Physics, 2017, 34 (4): 453- 460.
22	QASEMINEJAD R A. Modelling multiphase flow through micro-CT image of the pore space[D]. London: Imperial College London, 2013, 135.
23	李昂, 于浩波, 谢斌, 等. 基于有限体积法的致密油储层数字岩心中流动与传热研究[J]. 测井技术, 2017, 41 (2): 135- 140.
24	朱洪林. 低渗砂岩储层孔隙结构表征及应用研究[D]. 成都: 西南石油大学, 2014.
25	刘向君, 熊健, 梁利喜, 等. 基于微CT技术的致密砂岩孔隙结构特征及其对流体流动的影响[J]. 地球物理学进展, 2017, 32 (3): 1019- 1028.
26	OLSSON E, KREISS G. A conservative level set method for two phase flow[J]. Journal of Computational Physics, 2005, 210 (1): 225- 246. DOI
27	ROY S, RAJU R, CHUANG H F, et al. Modeling gas flow through microchannels and nanopores[J]. Journal of Applied Physics, 2003, 93 (8): 4870- 4879. DOI
28	COLIN S. Rarefaction and compressibility effects on steady and transient gas flows in micro-channels[J]. Microfluidics and Nanofluidics, 2005, 1 (3): 268- 279. DOI
29	OSHER S, SETHIAN J A. Fronts propagating with curvature-dependent speed: Algorithms based on Hamilton-Jacobi formulations[J]. Journal of Computational Physics, 1988, 79 (1): 12- 49. DOI
30	OLSSON E, KREISS G, ZAHEDI S. A conservative level set method for two phase flow Ⅱ[J]. Journal of Computational Physics, 2007, 225 (1): 785- 807. DOI
31	SUSSMAN M, ALMGREN A S, BELL J B, et al. An adaptive level set approach for incompressible two-phase flows[J]. J Comput Phys, 1997, 148 (1): 81- 124.
32	SHEPEL S V, SMITH B L. New finite-element/finite-volume level set formulation for modeling two-phase incompressible flows[J]. Journal of Computational Physics, 2006, 218 (2): 479- 494. DOI
33	LI B, LIU Q S, XU J W, et al. A new method for removing mixed noises[J]. Science in China Series F: Information Sciences, 2011, 54 (1): 51- 59. DOI
34	王平全, 陶鹏, 刘建仪, 等. 基于数字岩心的低渗透储层微观渗流机理研究[J]. 非常规油气, 2016, 3 (6): 1- 5. DOI

[1]	Renyi CAO, Tao HUANG, Linsong CHENG, Zhanwu GAO, Zhihao JIA. Influence of Polar Substance of Crude Oil on Adsorption and Wettability in Water Flooding Reservoir: Molecular Simulation [J]. Chinese Journal of Computational Physics, 2021, 38(5): 595-602.
[2]	Hubao A, Zhibing YANG, Ran HU, Yifeng CHEN. Molecular Dynamics Simulations of Capillary Dynamics at the Nanoscale [J]. Chinese Journal of Computational Physics, 2021, 38(5): 603-611.
[3]	CHAI Rukuan, LIU Yuetian, WANG Junqiang, XIN Jing, PI Jian, LI Changyong. Molecular Dynamics Simulation of Wettability of Calcite and Dolomite [J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2019, 36(4): 474-482.
[4]	DUAN Maochang, YU Xijun, CHEN Dawei, HUANG Chaobao, AN Na. DG Method for Compressible Gas-Solid Two-phase Flow [J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2017, 34(6): 631-640.
[5]	SUN Jingjing, HUANG Zhaoqin, YAO Jun, LI Aifen, WANG Daigang. Numerical Simulation of Water Flooding Development in Low Permeability Reservoirs with a Discrete Fracture Model [J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2015, 32(2): 177-185.
[6]	ZHANG Renliang, DI Qinfeng, WANG Xinliang, GU Chunyuan, WANG Wenchang. Lattice Boltzmann Simulation of Flow in a Micro-channel [J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2011, 28(2): 225-229.