in this paper, the mixed-mode dynamic fracture analysis of a fgm plate is performed using mlpg method also the effect of changes in value and angle of material gradation on the dynamic stress intensity fctor(sif) of mode i, ii, and effective are investigated. to solve time dependent equations that discretized by mlpg method, the central difference method (cdm) and the newmark method are used. a...

A large number of natural cracks exist in shale reservoirs, and the presence weakens integrity shale, which is an important factor governing effectiveness gas extraction. In this paper, shales from Lower Cambrian Niutitang Formation northern Guizhou were scanned by electron microscopy, their microstructures selected for digital image processing, uniaxial compression numerical tests conducted on...

More than half of all hydrocarbon reservoirs are Naturally Fractured Reservoirs (NFRs), in which production forecasting is a complicated function of fluid flow in a fracture-matrix system. Modelling of fluid flow in NFRs is challenging due to formation heterogeneity and anisotropy. Stress sensitivity and depletion effect on already-complex reservoir permeability add to the sophistication. Horiz...

Abstract There are many factors which influence the absolute open flow potential (AOFP) of gas well. One them is angle between maximum principal stress direction and natural fracture strike in reservoir. In order to find out how influences AOFP A lot data related well productivity 14 wells located reservoir T were collected collated. Influential intensity each factor on before after modificatio...

For the study of driving forces behind fault activation and its influencing factors on barrier effect rock mass movement under influence mining, discrete element numerical simulation software 3DEC was used for analysis impact distance to mining area from fault, buried depth upper boundary dip angle size thickness zone respectively. The results show that areas are closer as distances decrease, b...

The characterization of heterogeneous fracture patterns in complex reservoirs, such as folds, is difficult, as multiple stages of fracturing and fracture reactivation take place pre-, synand post-folding. Outcrop studies help understand the behavior of fractures and subsequent fluid flow in folds, as outcrops provide both small-scale fracture patterns and the large-scale fold geometry. We aim a...

The porosity, permeability, rock material and fracture networks of the newly discovered tight carbonate reservoir rock, Early Cretaceous Sarmord Formation in Zagros basin are examined. methods used to investigate formation cores, micro-resistivity image logs, drill stem tests, drilling fluid data, petrophysical wireline data drilled cutting samples. analysed show that is characterized by extens...

x-100 steel is one of the most recently developed materials for production of gas transportation pipelines. this material is severely anisotropic. smooth and notched round bars with different notch radius and flat notched specimens with different notch radius and notch depth in tension are tested to characterize the failure of this material under quasi-static loading condition. triaxiality fact...

It has been widely reported that coal permeability can change from reduction to enhancement due to gas adsorption even under the constant effective stress condition, which is apparently inconsistent with the classic theoretical solutions. This study addresses this inconsistency through explicit simulations of the dynamic interactions between coal matrix swelling/shrinking induced damage and fra...