Query:
学者姓名:周剑
Refining:
Year
Type
Indexed by
Source
Complex
Co-Author
Language
Clean All
Abstract :
Hot dry rock (HDR) is deep geothermal reservoir rock predominantly containing granite, whose physical and mechanical properties are governed by heterogeneous crystal structures. However, the fluid conductivity of intact granite with ultra-low permeability cannot be reformed using existing techniques. Complex fracture networks must be created by connecting hydraulic fractures with natural fractures developed in reservoirs. In this study, we introduce the wall barrier method into the novel hydro-grain-based model (hydro-GBM) to build a prefractured granite model at the mineral grain scale. This model enables investigation of the effects of the stress environment, mineral spatial distribution, and fluid injection rate on hydraulic fracturing characteristics. Microcracks around the inner tips of pre-existing fractures reproduce the initiation, propagation, and coalescence behaviors similar to experimental results. Mineral spatial distributions induce random changes in the propagation paths of hydraulic fractures. Increasing the fluid injection rate delays the deflection of hydraulic fractures and extends the propagation distance along the major axes of pre-existing fractures. The average activity level and proportion of large seismic events are reduced by injecting low-rate fluid. In summary, our results reveal the interactions between hydraulic and pre-existing fractures and provide a valuable reference for constructing an efficient enhanced geothermal system (EGS) for deep reservoirs.
Keyword :
Microcracking behavior Microcracking behavior Hydraulic fracturing Hydraulic fracturing Acoustic emission Acoustic emission Pre-existing fracture Pre-existing fracture Grain-based model Grain-based model Particle flow code Particle flow code
Cite:
Copy from the list or Export to your reference management。
GB/T 7714 | Wang, Song , Zhou, Jian , Zhang, Luqing et al. Numerical investigation of interactions between hydraulic and pre-existing opening-mode fractures in crystalline rocks based on a hydro-grain-based model [J]. | GEOENERGY SCIENCE AND ENGINEERING , 2023 , 229 . |
MLA | Wang, Song et al. "Numerical investigation of interactions between hydraulic and pre-existing opening-mode fractures in crystalline rocks based on a hydro-grain-based model" . | GEOENERGY SCIENCE AND ENGINEERING 229 (2023) . |
APA | Wang, Song , Zhou, Jian , Zhang, Luqing , Han, Zhenhua , Kong, Yanlong . Numerical investigation of interactions between hydraulic and pre-existing opening-mode fractures in crystalline rocks based on a hydro-grain-based model . | GEOENERGY SCIENCE AND ENGINEERING , 2023 , 229 . |
Export to | NoteExpress RIS BibTex |
Abstract :
The mechanical characteristics of gas hydrate-bearing sediments (HBS) are important for evaluating reservoir stability. The interbedded formation of HBS is common in target mining reservoirs. Existing studies on the triaxial mechanical properties of HBS are primarily based on homogeneous and isotropic samples. Therefore, the stress-strain law of the target mining reservoirs cannot be predicted accurately. In this study, a series of sediment models with interlayers of coarse and fine mineral grains were established based on the PFC3D code, and the influence of the layered distribution characteristics of sediment particles and hydrates on the macroscopic mechanical behaviour of the reservoir was comprehensively analysed. The triaxial compression simulation results indicate that the peak strength, deformation modulus, and cohesion of the layered HBS are significantly lower than those of the homogeneous model. The deformation modulus of the reservoir is mainly affected by the fine-grained layer without hydrates. When the coarse and fine grains correspond to different mineral components, the two minerals are heterogeneous in terms of their micromechanical parameters, which can further reduce the macroscopic mechanical parameters of the HBS. In addition, the layered distribution of hydrate results in significant anisotropy of the reservoir. This study constitutes a reference regarding the control mechanism of gas hydrate reservoir strength.
Keyword :
triaxial compression simulation triaxial compression simulation mechanical properties mechanical properties anisotropy anisotropy layered hydrate-bearing sediments layered hydrate-bearing sediments
Cite:
Copy from the list or Export to your reference management。
GB/T 7714 | Han, Zhenhua , Zhang, Luqing , Zhou, Jian et al. Effect of Mineral Grain and Hydrate Layered Distribution Characteristics on the Mechanical Properties of Hydrate-Bearing Sediments [J]. | ENERGIES , 2023 , 16 (21) . |
MLA | Han, Zhenhua et al. "Effect of Mineral Grain and Hydrate Layered Distribution Characteristics on the Mechanical Properties of Hydrate-Bearing Sediments" . | ENERGIES 16 . 21 (2023) . |
APA | Han, Zhenhua , Zhang, Luqing , Zhou, Jian , Pan, Zhejun , Wang, Song , Li, Ruirui . Effect of Mineral Grain and Hydrate Layered Distribution Characteristics on the Mechanical Properties of Hydrate-Bearing Sediments . | ENERGIES , 2023 , 16 (21) . |
Export to | NoteExpress RIS BibTex |
Abstract :
Activating closed natural fractures (NFs) in hot dry rock (HDR) reservoirs is a critical way to improve fluid conductivity and stimulate production. However, the current hydraulic fracturing simulation technology is limited in its ability to investigate the interaction mechanism between hydraulic fractures (HFs) and NFs under the interference of mineral heterogeneity in HDR. In this study, we combine a modified hydro-grain-based model (hydro-GBM) and the smooth joint model (SJM) to establish a discrete element model of granite with closed NFs, investigating the effects of in-situ stress, approach angle, and physico-mechanical properties of NFs on interaction modes. Our results show that mineral heterogeneity induces HFs on both sides of the borehole to propagate asymmetrically along low-strength minerals and mineral boundaries, enhancing the complexity of HFs. As the approach angle, NF interface friction coefficient, or NF bond strengths decrease and differential in-situ stress or NF permeability increases, the offset of HFs propagating along NFs increases, thus promoting the activation degree of NFs and resulting in a decline in the average activity level of acoustic emission (AE) events and the proportion of large events in NFs. Furthermore, numerical simulations reveal the evolution laws of fracturing results, such as breakdown pressure, fracture propagation pressure, spatial distribution of microcracks, fluid pressure field, and normal stresses on NFs, which provide valuable insights for constructing complex and efficient fracture networks in HDR reservoirs. A smooth joint coupling hydro-grain-based model is proposed to describe the crystalline rock with closed natural fractures from the mineral grain scale.The model reproduces the interaction modes between hydraulic fractures and natural fractures similar to the experimental results.Effects of in-situ stress, approach angle, and physico-mechanical properties of natural fractures on interaction processes are deeply analyzed.Evolution laws of normal stresses and AE responses for natural fractures during interactions are revealed.
Keyword :
Particle flow code Particle flow code Hydraulic fracturing Hydraulic fracturing Fracture propagation behavior Fracture propagation behavior Grain-based model Grain-based model Sensitivity analysis Sensitivity analysis Natural fracture Natural fracture
Cite:
Copy from the list or Export to your reference management。
GB/T 7714 | Wang, Song , Zhou, Jian , Zhang, Luqing et al. Modeling Interactions between Hydraulic and Closed Natural Fractures in Brittle Crystalline Rocks: A Fluid-Solid Coupling Grain-Based Approach for Characterizing Microcracking Behaviors [J]. | ROCK MECHANICS AND ROCK ENGINEERING , 2023 , 57 (2) : 889-920 . |
MLA | Wang, Song et al. "Modeling Interactions between Hydraulic and Closed Natural Fractures in Brittle Crystalline Rocks: A Fluid-Solid Coupling Grain-Based Approach for Characterizing Microcracking Behaviors" . | ROCK MECHANICS AND ROCK ENGINEERING 57 . 2 (2023) : 889-920 . |
APA | Wang, Song , Zhou, Jian , Zhang, Luqing , Han, Zhenhua , Kong, Yanlong . Modeling Interactions between Hydraulic and Closed Natural Fractures in Brittle Crystalline Rocks: A Fluid-Solid Coupling Grain-Based Approach for Characterizing Microcracking Behaviors . | ROCK MECHANICS AND ROCK ENGINEERING , 2023 , 57 (2) , 889-920 . |
Export to | NoteExpress RIS BibTex |
Abstract :
Hydraulic fracturing, which determines geothermal resource productivity, is one of the critical technical components in the construction of hot dry rock (HDR) reservoirs. Although the mechanical coupling between solid and fluid has been included in algorithms based on the discrete element method (DEM) generally employed to investigate hydraulic fracturing, crystalline rocks of reservoirs are mostly treated as homogeneous isotropic models without considering their petrographic texture. By combining a grain-based model (GBM) and a modified fluid-solid coupling algorithm, a novel hydro-GBM is constructed in this study to analyze the hydraulic fracturing response of polycrystalline rocks. Moreover, acoustic emission (AE) events during fracturing are extracted to describe the characteristics of hydraulic-fracturing-induced seismicity. Under in-situ conditions with high differential stress, the propagation direction of hydraulic fractures is mainly perpendicular to the direction of minimum in-situ stress, with little influence by material heterogeneity and fluid viscosity; under near-hydrostatic in-situ stress conditions, the microcracks along the mineral boundaries increase remarkably, and the fracture pattern tends to be complex, especially when a low-viscosity fluid is injected into the rock. From the Gutenberg-Richter type relationship between the AE event numbers and the moment magnitudes, it is found that large induced seismic events increase with in-situ stress and with fluid viscosity. In summary, the proposed hydro-GBM can well reproduce the propagation behavior of hydraulic fractures influenced by material heterogeneity, and the research results reveal the interactions between petrographic texture, in-situ stress, fluid viscosity, and hydraulic fracturing characteristics, which will provide a valuable reference for on-site reservoir stimulation.
Keyword :
Grain-based model Grain-based model Fluid-solid coupling algorithm Fluid-solid coupling algorithm Acoustic emission Acoustic emission Particle flow code Particle flow code Hydraulic fracturing Hydraulic fracturing Micro-cracking behavior Micro-cracking behavior
Cite:
Copy from the list or Export to your reference management。
GB/T 7714 | Wang, Song , Zhou, Jian , Zhang, Luqing et al. Modeling Injection-Induced Fracture Propagation in Crystalline Rocks by a Fluid-Solid Coupling Grain-Based Model [J]. | ROCK MECHANICS AND ROCK ENGINEERING , 2023 , 56 (8) : 5781-5814 . |
MLA | Wang, Song et al. "Modeling Injection-Induced Fracture Propagation in Crystalline Rocks by a Fluid-Solid Coupling Grain-Based Model" . | ROCK MECHANICS AND ROCK ENGINEERING 56 . 8 (2023) : 5781-5814 . |
APA | Wang, Song , Zhou, Jian , Zhang, Luqing , Nagel, Thomas , Han, Zhenhua , Kong, Yanlong . Modeling Injection-Induced Fracture Propagation in Crystalline Rocks by a Fluid-Solid Coupling Grain-Based Model . | ROCK MECHANICS AND ROCK ENGINEERING , 2023 , 56 (8) , 5781-5814 . |
Export to | NoteExpress RIS BibTex |
Abstract :
As anthropogenic antibiotics, quinolones, e.g., ofloxacin have adverse impacts on ecological systems and human heaths. The removal of quinolones is of great importance, and adsorption techniques have been widely used to remove this hazardous contaminant. However, a robust and easy-operating adsorbent is still emergently required due to the complex chemical structure of quinolones. In this study, we successfully synthesized the promising metallic carbons (MCs) containing carbon nanotubes and cobalt nanoparticles by carbonizing Zn/Co-ZIF at 900 degrees C. Three different molar ratios of Co and Zn were applied to optimize the adsorption capacity on ofloxacin (OFL). Results showed MC with molar ratio of Co and Zn at 3:1 (Co-CNT/NPC3/1) achieved the maximal adsorption capacity to 118.3 mg g-1. Its adsorption performance was satisfied in the pH range from 5 to 9 and ionic strengths at 0.01 M. The main mechanisms for these adsorptions were identified as electrostatic attraction, metal coordination and pi-pi EDA. Removal efficiencies of quinolones higher than 68 mg g-1 indicated the strong feasibility of this adsorbent for wastewater treatments. The regeneration of Co-CNT/NPC3/1 at 600 degrees C allowed its at least 4-time reusability and its magnetic property enabled external magnets to recycle it from real environments.
Keyword :
Magnetic separation Magnetic separation Adsorption Adsorption Zn Zn Co zeolitic imidazolate frameworks Co zeolitic imidazolate frameworks Metallic carbides Metallic carbides
Cite:
Copy from the list or Export to your reference management。
GB/T 7714 | Liang, Yixuan , Zhang, Qiyu , Li, Sumei et al. Highly efficient removal of quinolones by using the easily reusable MOF derived-carbon [J]. | JOURNAL OF HAZARDOUS MATERIALS , 2022 , 423 . |
MLA | Liang, Yixuan et al. "Highly efficient removal of quinolones by using the easily reusable MOF derived-carbon" . | JOURNAL OF HAZARDOUS MATERIALS 423 (2022) . |
APA | Liang, Yixuan , Zhang, Qiyu , Li, Sumei , Fei, Jiaying , Zhou, Jian , Shan, Saisai et al. Highly efficient removal of quinolones by using the easily reusable MOF derived-carbon . | JOURNAL OF HAZARDOUS MATERIALS , 2022 , 423 . |
Export to | NoteExpress RIS BibTex |
Abstract :
Longyou Grottoes, the underground projects with a rich history of thousands of years, are one of the key cultural relics to be protected in China and are actively preparing to apply for a world cultural heritage site. However, due to the shallow buried argillaceous siltstone with low-strength bedding planes, some cavern roofs experienced apparent breakages or large-scale collapses. Clarifying the roof deformation and failure mechanism is essential for the long-term protection of the historical relic and sustainable development of tourism. Productive previous work proved that three-point bending tests of rock samples could reproduce stress states of cavern roofs. Therefore, three-point bending numerical models with various bedding plane structures for Longyou argillaceous siltstone are created in this study to investigate the rock mechanical behaviors. The simulation results show that as bedding mechanical properties decrease, the bending strength (BS) has a slow to fast decrease, indicating that timely protection in Longyou Grottoes before the BS drops sharply is conducive to preventing roof failures. This declining trend is further accelerated when the bedding dip angle changes from horizontal to vertical. Dip angles, mechanical properties, and spacings of bedding planes control fracture modes of models. Moreover, the fitted Gutenberg-Richter-type relationships between acoustic emission (AE) moment magnitudes and logarithmic AE events present high average activity levels and high proportions of large AE events in both bedding planes and rock matrix for models with strong, dispersedly distributed, and near-horizontal bedding planes. In summary, the simulation results reveal the impacts of transverse isotropy in surrounding rocks on roof bending failures, which may provide a valuable reference for the reinforcement and protection of Longyou Grottoes.
Keyword :
Transverse isotropy Transverse isotropy Three-point bending test Three-point bending test Micro -cracking behavior Micro -cracking behavior Longyou Grottoes Longyou Grottoes Particle flow code Particle flow code
Cite:
Copy from the list or Export to your reference management。
GB/T 7714 | Wang, Song , Zhou, Jian , Zhang, Luqing et al. Numerical studies on micro-cracking behavior of transversely isotropic argillaceous siltstone in Longyou Grottoes under three-point bending [J]. | THEORETICAL AND APPLIED FRACTURE MECHANICS , 2022 , 122 . |
MLA | Wang, Song et al. "Numerical studies on micro-cracking behavior of transversely isotropic argillaceous siltstone in Longyou Grottoes under three-point bending" . | THEORETICAL AND APPLIED FRACTURE MECHANICS 122 (2022) . |
APA | Wang, Song , Zhou, Jian , Zhang, Luqing , Han, Zhenhua , Zhang, Fenxiang , Fu, Yan et al. Numerical studies on micro-cracking behavior of transversely isotropic argillaceous siltstone in Longyou Grottoes under three-point bending . | THEORETICAL AND APPLIED FRACTURE MECHANICS , 2022 , 122 . |
Export to | NoteExpress RIS BibTex |
Abstract :
基于离散颗粒模型的岩体结构面动-静态刚度系数对比的数值模拟研究
Keyword :
黏结颗粒模型 黏结颗粒模型 吸收边界模型 吸收边界模型 结构面刚度系数反演 结构面刚度系数反演 接触模型 接触模型 应力波传播 应力波传播
Cite:
Copy from the list or Export to your reference management。
GB/T 7714 | 周剑 , 王彦兵 , 张路青 et al. 基于离散颗粒模型的岩体结构面动-静态刚度系数对比的数值模拟研究 [J]. | 周剑 , 2021 , 29 (1) : 25-33 . |
MLA | 周剑 et al. "基于离散颗粒模型的岩体结构面动-静态刚度系数对比的数值模拟研究" . | 周剑 29 . 1 (2021) : 25-33 . |
APA | 周剑 , 王彦兵 , 张路青 , 金永军 , 涂新斌 , 工程地质学报 . 基于离散颗粒模型的岩体结构面动-静态刚度系数对比的数值模拟研究 . | 周剑 , 2021 , 29 (1) , 25-33 . |
Export to | NoteExpress RIS BibTex |
Abstract :
The grain-based model (GBM) in two-dimensional Particle Flow Code (PFC2D) is widely employed to investigate the mechanical response characteristics of crystalline rocks under external load considering the realistic petrographic texture. However, due to the poor self-locking effect of the Parallel-Bond (PB) inside the minerals and unreasonable parametric assignment for the Smooth-Joint (SJ) at the mineral boundaries, the original GBM cannot reproduce the exact microcracking process of brittle rocks. To solve the problem, the novel grain-based model (nGBM) composed of the Flat-Joint (FJ) and the SJ was proposed in our previous research, which not only enhances the rotational resistance of particles, but also improves the simulation of the mineral boundaries. In this study, the nGBM was carefully established and calibrated based on the properties of Alxa porphyritic granite. A series of simulation tests of uniaxial compression, triaxial compression and direct tension under different mineral boundary parametric conditions were carried out to observe the deformation, microcracking and failure behaviors of the nGBM. Quantitative analyses of the mineral boundary properties and the mechanical behaviors of the numerical specimen revealed the extremely complicated relationships between them, which can help explain the micromechanical damage process of crystalline rocks and provide valuable reference for the model calibration. © 2020 Elsevier Ltd
Keyword :
Textures Textures Crystalline rocks Crystalline rocks Microcracking Microcracking Minerals Minerals
Cite:
Copy from the list or Export to your reference management。
GB/T 7714 | Wang, Song , Zhou, Jian , Zhang, Luqing et al. Parameter studies on the mineral boundary strength influencing the fracturing of the crystalline rock based on a novel Grain-Based Model [J]. | Engineering Fracture Mechanics , 2021 , 241 . |
MLA | Wang, Song et al. "Parameter studies on the mineral boundary strength influencing the fracturing of the crystalline rock based on a novel Grain-Based Model" . | Engineering Fracture Mechanics 241 (2021) . |
APA | Wang, Song , Zhou, Jian , Zhang, Luqing , Han, Zhenhua , Zhang, Fenxiang . Parameter studies on the mineral boundary strength influencing the fracturing of the crystalline rock based on a novel Grain-Based Model . | Engineering Fracture Mechanics , 2021 , 241 . |
Export to | NoteExpress RIS BibTex |
Abstract :
Developing efficient photocatalysts for CO2 reduction into value-added chemical feedstocks is of significance. Heterojunction photocatalysts are promising candidates but still suffering from the insufficient electron-hole pair separation issues. Herein, a strategy that dual metal–organic frameworks (MOFs) template-directed fabrication of carbon-supported heterojunction, C-In2O3@MO (MO = ZnO, Co3O4, and ZnCo2O4) with tunable band matching structure was developed. The resultant hollow- structured C-In2O3@ZnCo2O4 shows high CO2 reduction activity towards CO (44.1 μmol g1 h−1) with a selectivity of 66%. The superior performance of this material could be ascribed to the suitable energy band matching and efficient internal charge transfer on p-n heterojunction, which facilitates electron-hole separation. Meanwhile, the hollow cavity not only improved light-harvesting capability through multiple light reflection and scattering in the internal voids but also provided large surface area for exposing active sites to promoting the activation of CO2. This study thus proposes a feasible approach to adjust the heterojunction structure of photocatalysts to achieve efficient CO2 reduction reaction. © 2021 Elsevier B.V.
Keyword :
Indium compounds Indium compounds II-VI semiconductors II-VI semiconductors Carbon dioxide Carbon dioxide Fabrication Fabrication Zinc oxide Zinc oxide Light reflection Light reflection Charge transfer Charge transfer Heterojunctions Heterojunctions
Cite:
Copy from the list or Export to your reference management。
GB/T 7714 | Zhao, Chen , Zhou, Awu , Dou, Yibo et al. Dual MOFs template-directed fabrication of hollow-structured heterojunction photocatalysts for efficient CO2 reduction [J]. | Chemical Engineering Journal , 2021 , 416 . |
MLA | Zhao, Chen et al. "Dual MOFs template-directed fabrication of hollow-structured heterojunction photocatalysts for efficient CO2 reduction" . | Chemical Engineering Journal 416 (2021) . |
APA | Zhao, Chen , Zhou, Awu , Dou, Yibo , Zhou, Jian , Bai, Jinquan , Li, Jian-Rong . Dual MOFs template-directed fabrication of hollow-structured heterojunction photocatalysts for efficient CO2 reduction . | Chemical Engineering Journal , 2021 , 416 . |
Export to | NoteExpress RIS BibTex |
Abstract :
Mineral grain size heterogeneity is one of the fundamental reasons leading to differences in rock mechanical behaviours. Several indices have been proposed to quantify grain size heterogeneity, however, the applicability of the existing indices is limited due to various preconditions. An improved grain size heterogeneity index H-e was proposed in this study. By comparing with the previous index, the improved index was proved to be more applicable for analysing rock mechanical properties. Through a series of grain-based model (GBM), the grain size heterogeneity effect, material heterogeneity effect and mineral content effect were further discussed. For a simple grain size heterogeneity effect, the crack initiation stress, damage stress, peak stress and crack initiation stress ratio of rock decreased linearly as the improved index H-e increased. After accounting for the material heterogeneity effect, the above characteristic stresses and elastic modulus decreased. A significant material heterogeneity effect and mineral content effect will impact the linear correlation between the rock macromechanical parameters and the H-e index. When the axial stress was low, the grain size heterogeneity had little effect on the number of microcracks, but this heterogeneity became the main factor affecting the evolution of microcracks as the axial stress increased. The number of intragrain tensile cracks increases and the number of intergrain shear cracks decreases with increasing H-e, when the axial stress reached the rock peak strength. Besides, the combined effects of material heterogeneity and mineral content may control the type and number of microcracks, further weakening the effect of grain size heterogeneity.
Keyword :
Particle flow code Particle flow code Alxa granite Alxa granite Heterogeneity index Heterogeneity index Grain-based modelling Grain-based modelling Grain size heterogeneity Grain size heterogeneity
Cite:
Copy from the list or Export to your reference management。
GB/T 7714 | Han, Zhenhua , Zhang, Luqing , Azzam, Rafig et al. A statistical index indicating the degree and mechanical effects of grain size heterogeneity in rocks [J]. | ENGINEERING GEOLOGY , 2021 , 293 . |
MLA | Han, Zhenhua et al. "A statistical index indicating the degree and mechanical effects of grain size heterogeneity in rocks" . | ENGINEERING GEOLOGY 293 (2021) . |
APA | Han, Zhenhua , Zhang, Luqing , Azzam, Rafig , Zhou, Jian , Wang, Song . A statistical index indicating the degree and mechanical effects of grain size heterogeneity in rocks . | ENGINEERING GEOLOGY , 2021 , 293 . |
Export to | NoteExpress RIS BibTex |
Export
Results: |
Selected to |
Format: |