Results 61 to 70 of about 2,317,450 (234)
The graphical abstract presents a structured decision‐support framework for assessing the feasibility of converting depleted oil and gas wells into geothermal energy systems. The left panel illustrates a comprehensive, multi‐stage decision‐making framework progressing from prefeasibility screening and technical–economic analysis to policy alignment ...
Karolina Bieryt +3 more
wiley +1 more source
Study on cleat structure and its influence on wellbore stability in coal seams
In order to illustrate the influences of the in-situ stress heterogeneity and cleat angle on wellbore stability of coal seam, the following researches have been done.
WANG Yuepeng +3 more
doaj
This study quantitatively analyzed the spatiotemporal evolution of stress redistribution ahead of the working face by integrating coal seam distribution, tectonic stress anomalies, gas pressure, and mining‐induced disturbances. An R‐value criterion for coal and gas outburst (CGO) risk assessment was established based on energy principles.
Yingjie Zhao +7 more
wiley +1 more source
A stress wave propagation model for coal‐rock combinations under in situ stress was established. Taking a coal mine in Huainan, China as the engineering background, isotropic and anisotropic numerical models were constructed. Field engineering practices were carried out to verify the reliability of the conclusions.
Jianyu Zhang +6 more
wiley +1 more source
One‐way FLAC3D‐COMSOL coupled modeling and field validation show that a 150 mm borehole radius with 5 m spacing provides the best coordination of plastic‐zone expansion, stress relief, permeability enhancement, and gas‐pressure attenuation, increasing the pure gas drainage rate by 35.4%. ABSTRACT To rationally determine the borehole radius and borehole
Yewu Bi +7 more
wiley +1 more source
Impact of rock strength degradation by fluid intrusion on borehole stability in shale
The interaction between shale bedding planes and fluids significantly weakens their structural integrity, profoundly affecting borehole stability in shale reservoirs. However, traditional analyses often overlook fluid intrusion from the borehole into the
Heyuan Wang +5 more
doaj +1 more source
Study on Roof‐Control Technology for Gob‐Side Entry Retaining Under Composite Roofs
This study develops a roof‐control technology system for gob‐side entry retaining under composite roofs. By integrating field measurements, theoretical analysis, and numerical simulation, it reveals the spatiotemporal evolution of the plastic zone and proposes a targeted support method, providing theoretical and practical guidance for safe and ...
Dong Li +4 more
wiley +1 more source
This study addresses hard roof coal seam conditions by optimizing key stratum blasting‐cutting parameters through theoretical analysis, numerical simulation, and field tests. It proposes calculation methods for blast hole spacing and delay timing based on stress wave theory, controlling roadway deformation within 35 mm, thereby enhancing resource ...
Qiong Liu, Duanxiang Fu, Hongbin Li
wiley +1 more source
Thermal Characteristics of Borehole Stability Drilling in Hot Dry Rock. [PDF]
Zhu Z, Wang C, Guan Z, Lei W.
europepmc +1 more source
This study on close coal seams shows that multi‐seam mining increases the height of the fractured zone from approximately 26 m (single upper‐seam mining) to about 49 m. When the lower seam is mined after the extraction of the upper seam, the heights of both the caved zone and the fractured zone increase by approximately two times.
Xiaoyu Wu +4 more
wiley +1 more source

