Fan Yang^1,2,*, Honggang Mi^1,2, Jian Wu^1,2, Qi Yang^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.11, pp. 2637-2656, 2024, DOI:10.32604/fdmp.2024.048574 - 28 October 2024

Abstract The gas production of deep coalbed methane wells in Linxing-Shenfu block decreases rapidly, the water output is high, the supporting effect is poor, the effective supporting fracture size is limited, and the migration mechanism of proppant in deep coal reservoir is not clear at present. To investigate the migration behavior of proppants in complex fractures during the volume reconstruction of deep coal and rock reservoirs, an optimization test on the conductivity of low-density proppants and simulations of proppant migration in complex fractures of deep coal reservoirs were conducted. The study systematically analyzed the impact of… More >

Shangjun Gao^1,2, Yang Yang¹, Man Chen¹, Jian Zheng¹, Luqi Qin^2,*, Xiangyu Liu², Jianying Yang¹

Energy Engineering, Vol.121, No.11, pp. 3305-3329, 2024, DOI:10.32604/ee.2024.053622 - 21 October 2024

Abstract Horizontal well drilling and multi-stage hydraulic fracturing are key technologies for the development of shale gas reservoirs. Instantaneous acquisition of hydraulic fracture parameters is crucial for evaluating fracturing effectiveness, optimizing processes, and predicting gas productivity. This paper establishes a transient flow model for shale gas wells based on the boundary element method, achieving the characterization of stimulated reservoir volume for a single stage. By integrating pressure monitoring data following the pumping shut-in period of hydraulic fracturing for well testing interpretation, a workflow for inverting fracture parameters of shale gas wells is established. This new method… More >

Hongzhao Li¹, Peidong Li^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.29, No.2, pp. 1-1, 2024, DOI:10.32604/icces.2024.012711

Abstract Quasicrystals (QCs) are a new class of functional and structural materials with unusual properties, which have quasi-periodic translational symmetry and non-crystallographic rotational symmetry. Due to the special arrangement of atoms, compared with traditional materials, QCs have high strength, high hardness, and high wear resistance, and can be used as a particle reinforcement phase of polymer or metal matrix composites to improve the performance of materials. QC composites are a special type of composites in which the high strength and hardness of QCs can effectively enhance the mechanical properties of the composites while maintaining the lightweight… More >

Yong Pang¹, Peidong Li^1,*, Dingyu Li²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.29, No.2, pp. 1-1, 2024, DOI:10.32604/icces.2024.011660

Abstract The thermo-elastic fracture problems of functionally graded materials (FGMs) are thoroughly investigated based on a phase field model. In this model, the material constants and fracture toughness vary with the spatial coordinates, the thermal conductivity and stiffness constants in the damaged regions are degraded by the phase-field variable, and the crack evolution is driven by the variation of elastic energy induced by the thermo-mechanical loading. Therefore, the temperature, mechanical and damage fields are coupled with each other. The finite element discretization of the governing equations and the numerical implementation details are provided. The validation of… More >

Shaoqi Zheng¹, Zihao Yang^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.29, No.1, pp. 1-1, 2024, DOI:10.32604/icces.2024.012200

Abstract This study proposes a novel method for predicting the microcrack propagation in composites based on coupling the local and non-local micromechanics. The special feature of this method is that it can take full advantages of both the continuum micromechanics as a local model and peridynamic micromechanics as a non-local model to achieve composite fracture simulation with a higher level of accuracy and efficiency. Based on the energy equivalence, we first establish the equivalent continuum micromechanics model with equivalent stiffness operators through peridynamic micromechanics model. These two models are then coupled into a closed equation system, More >

Hongjun Yu^1,*, Canjie Huang¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.29, No.1, pp. 1-1, 2024, DOI:10.32604/icces.2024.011454

Abstract A novel and irreversible phase field model accounting for tension-torsion coupling effect and size-effect is constructed in the context of continuum thermodynamics. First, a general framework considering the energy dissipation process influenced by micro and macro force is formulated according to thermodynamically consistent derivation. Next, the framework is specialized by introducing a material parameter called chiral coefficient to characterize the tension-torsion coupling effect within macro force constitutive according to isotropic micropolar elasticity theory. To gain insight of the chiral effect on the fracture behaviors, the analytical solution of uniaxial traction chiral rod is provided based More >

Sihui Tong¹, Boyuan Cao¹, Dongqing Tian², Qinwei Ma¹, Guangyan Liu^1,*, Li Shi², Libin Sun²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.29, No.1, pp. 1-1, 2024, DOI:10.32604/icces.2024.010870

Abstract Graphite materials serve critical roles as moderators, reflectors and core structural components in high-temperature gas-cooled nuclear reactors. These materials may experience a variety of loads during the reactor operation, including thermal, radiation, fatigue and dynamic loads, potentially leading to crack initiation and propagation. Consequently, it is imperative to investigate the fracture properties of graphite materials. Currently, there exists a dearth of comprehensive studies on the fracture toughness of graphite materials with varying grain sizes, especially regarding dynamic fracture toughness. This study introduces a novel approach utilizing a digital-image-correlation-based virtual extensometer to analyze crack propagation in… More >

Rajan Aravind^1,2, Sundararajan Natarajan¹, Krishnankutty Jayakumar², Ratna Kumar Annabattula^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.141, No.2, pp. 997-1032, 2024, DOI:10.32604/cmes.2024.053047 - 27 September 2024

Abstract Understanding the probabilistic nature of brittle materials due to inherent dispersions in their mechanical properties is important to assess their reliability and safety for sensitive engineering applications. This is all the more important when elements composed of brittle materials are exposed to dynamic environments, resulting in catastrophic fatigue failures. The authors propose the application of a non-intrusive polynomial chaos expansion method for probabilistic studies on brittle materials undergoing fatigue fracture when geometrical parameters and material properties are random independent variables. Understanding the probabilistic nature of fatigue fracture in brittle materials is crucial for ensuring the… More >

Mingjing Lu^1,2,*, Qin Qian¹, Anhai Zhong¹, Feng Yang¹, Wenjun He¹, Min Li¹

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.10, pp. 2281-2300, 2024, DOI:10.32604/fdmp.2024.051594 - 23 September 2024

Abstract Continental shale oil reservoirs, characterized by numerous bedding planes and micro-nano scale pores, feature significantly higher stress sensitivity compared to other types of reservoirs. However, research on suitable stress sensitivity characterization models is still limited. In this study, three commonly used stress sensitivity models for shale oil reservoirs were considered, and experiments on representative core samples were conducted. By fitting and comparing the data, the “exponential model” was identified as a characterization model that accurately represents stress sensitivity in continental shale oil reservoirs. To validate the accuracy of the model, a two-phase seepage mathematical model More >

Mingxu Zhang¹, Mingliang Wang², Wei Zhang^3,*

Structural Durability & Health Monitoring, Vol.18, No.5, pp. 599-622, 2024, DOI:10.32604/sdhm.2024.051949 - 19 July 2024

Abstract This paper examines the mechanical behavior of fiber reinforced polymer (FRP)-confined concrete under cyclic compression using the 3D cohesive zone model (CZM). A numerical modeling method was developed, employing zero-thickness cohesive elements to represent the stress-displacement relationship of concrete potential fracture surfaces and FRP-concrete interfaces. Additionally, mixed-mode damage plastic constitutive models were proposed for the concrete potential fracture surfaces and FRP-concrete interface, considering interfacial friction. Furthermore, an anisotropic plastic constitutive model was developed for the FRP composite jacket. The CZM model proposed in this study was validated using experimental data from plain concrete and large More >