Article
Mechanics
Qindong Lin, Shihai Li, Yundan Gan, Chun Feng
Summary: A strain-rate cohesive fracture model based on the Lennard-Jones potential and multi-scale model of rocks is established to characterize the dynamic mechanical response of rocks during crack initiation and propagation at high strain rates. The model explains the micro-mechanism of strain rate effect from the molecular scale and is verified to accurately simulate dynamic tensile and shear failures of rocks at different strain rates through numerical simulations. The results show that the model can predict dynamic tensile strength, dynamic compressive strength, and dynamic tensile fracture energy similar to laboratory tests.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Chemistry, Multidisciplinary
Anwar Al Rsheed, Saad Aldawood, Omar M. Aldossary
Summary: A model based on the Lennard-Jones potential function is proposed to calculate the melting points of nanoparticles, considering the effects of size, shape, atomic volume, and surface packing. The model for spherical nanoparticles agrees with experimental values and can predict the melting points accurately. The non-integer L-J potential function can also be used to predict the melting points of nanoparticles.
Article
Multidisciplinary Sciences
Omar M. Aldossary
Summary: A generalized non-integer Lennard-Jones (L-J) potential function with an additional parameter m is proposed and successfully predicts the cohesive energy and melting point of nanoparticles. The model shows excellent agreement with experimental values for various metallic nanoparticles, attributing the stability to the increase in range of attractive force and high gradient attractive interaction in the potential function.
JOURNAL OF KING SAUD UNIVERSITY SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Dan Wang, Zhili Hu, Gang Peng, Yajun Yin
Summary: This study investigates the impact of surface geometry on surface energy using the Lennard-Jones (L-J) pair potential and homogenization hypothesis. The accuracy of curvature-based surface energy is confirmed by comparing it with experimental results. The results show that surface energy decreases on convex surfaces and increases on concave surfaces, with the effect of curvatures becoming more pronounced at smaller scales.
Article
Computer Science, Interdisciplinary Applications
Sina Alemi Parvin, N. A. Ahmed, A. M. Fattahi
Summary: This research aimed to investigate the longitudinal elastic and effective modulus of composites reinforced with different types and volume fractions of carbon nanotubes through finite element simulation. The results showed that increasing volume fraction and aspect ratio led to higher elastic modulus and lower Poisson's ratio of the composite. Additionally, the type of nanotubes used also influenced the mechanical properties of the composite.
ENGINEERING WITH COMPUTERS
(2021)
Article
Materials Science, Characterization & Testing
Weifan Zheng, Yang Cheng, Xiao Ma, Hao Sui, Jiye Zhang
Summary: In this study, a new cellular automata model of traffic flow is proposed by introducing the Lennard-Jones potential into the interaction of vehicles. The model considers the driver's decision-making process and the stochastic behavior of traffic flow. Through numerical simulation, the model successfully reproduces complex traffic phenomena.
NONDESTRUCTIVE TESTING AND EVALUATION
(2023)
Article
Physics, Multidisciplinary
Davood Toghraie, Mohammad Ali Fazilati, Yasaman Salehipour, Maboud Hekmatifar, Roozbeh Sabetvand
Summary: In this study, the friction process in an atomic structure composed of an iron matrix in the presence of spherical aluminium nanoparticles is investigated using molecular dynamics simulation. The results show that increasing the normal load intensifies the friction process. Furthermore, increasing the collision angle increases the intra-atomic friction, while increasing the number of atomic layers reduces the destructive effect of the friction process.
EUROPEAN PHYSICAL JOURNAL PLUS
(2022)
Article
Chemistry, Medicinal
Beibei Wang, Shane Jackson, Aiichiro Nakano, Ken-ichi Nomura, Priya Vashishta, Rajiv Kalia, Mark Stevens
Summary: The principle of least action is fundamental in classical mechanics, theory of relativity, quantum mechanics, and thermodynamics. This paper describes how a neural network learns to find trajectories in a Lennard-Jones system and successfully predicts structural transformation pathways for LJ clusters. The neural network approach allows for efficient computation of atomic trajectories over time.
JOURNAL OF CHEMICAL INFORMATION AND MODELING
(2022)
Article
Chemistry, Physical
Krishan Kanhaiya, Seonghan Kim, Wonpil Im, Hendrik Heinz
Summary: The introduction of new Lennard-Jones parameters for simulating a wider range of fcc metals in this study enables accurate reproduction of physical properties such as lattice constants, surface energies, and water interfacial energies in experiments. These parameters are compatible with various force fields, potentially offering reliable simulations of nanostructures with millions of atoms.
NPJ COMPUTATIONAL MATERIALS
(2021)
Article
Physics, Fluids & Plasmas
Cedric Schoonen, James F. Lutsko
Summary: Classical density functional theory is used to calculate the fluid-solid surface tensions for low-index faces of crystals of hard spheres and Lennard-Jones particles. The results show that the recently introduced fundamental measure theory model has state-of-the-art accuracy compared to simulation. For the Lennard-Jones system, both solid-liquid and solid-vapor interfaces are studied, and the results are in good agreement with existing literature.
Article
Materials Science, Multidisciplinary
V Ladygin, I Beniya, E. Makarov, A. Shapeev
Summary: This study proposes a framework based on Gaussian process regression for reconstructing free-energy functions in phase diagram calculations, allowing for automatic convergence with simulation parameters. Validation of the methodology on two model systems confirms its effectiveness in phase diagram computations.
Article
Chemistry, Medicinal
Nicholas B. Smith, Tim Jowett, Diana Yu, Elke Pahl, Anna L. Garden
Summary: The basin-hopping algorithm (BHA) efficiently explores atomic cluster potential energy surfaces through random perturbations and energy minimizations in configuration space. In multifunnel systems, neither of the two modes of the taboo search method significantly improves performance.
JOURNAL OF CHEMICAL INFORMATION AND MODELING
(2023)
Article
Mechanics
Sebastian Pech, Markus Lukacevic, Josef Fuessl
Summary: Fracture mechanics simulations are essential for understanding wood failure, where microstructure greatly affects mechanical properties. The study utilizes a hybrid multi-phase field model that supports cohesive failure in orthotropic materials, with favorable fracture planes. The model demonstrates good agreement with experimental results and can be applied to more complex wood scenarios.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Biochemistry & Molecular Biology
Emilia Valenca Ferreira de Aragao, Luca Mancini, Noelia Faginas-Lago, Marzio Rosi, Dimitrios Skouteris, Fernando Pirani
Summary: In this study, a new theoretical approach is proposed to investigate the reaction between the cyano radical and cyanoacetylene molecule. The approach combines statistic RRKM calculations with a semiempirical analysis to derive the rate coefficient for this reaction. The obtained rate coefficient is compared with previous theoretical and experimental investigations, revealing the strengths and weaknesses of the new approach.
Review
Chemistry, Physical
Yu-Jie Chen, Wei Lu, Bo Yu, Wen-Quan Tao, Wenjing Zhou, Qun Cao
Summary: Bubble nucleation in boiling heat transfer is a microscale phenomenon. The commonly used molecular dynamics simulation method often requires an unreasonable heating temperature to achieve bubble nucleation in liquid argon. This study proposes a revised potential model for bubble nucleation study of argon, which can lower the onset nucleation temperature and avoid the unreasonable change of liquid argon properties.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Mechanics
Xiaolong Liu, Kelian Luo, Pengcheng Gao, Tao Cong, Xi Wang, Wenjing Wang
Summary: This paper investigates the formation mechanisms of the zig-zag crack region on the shattered rim of railway wheels. The zig-zag crack region, identified as a typical region for crack propagation in rolling contact fatigue behavior, was observed using scanning electron microscopy and transmission electron microscopy. The formation of the zig-zag morphology is attributed to the periodic deflection of the propagation path relative to the initial propagation plane, caused by the limited plastic deformation zone at the crack tip. Grain refinement and secondary cracks in the zig-zag crack region are a result of the large compressive and shear stresses induced by rolling contact loading.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Anastasia Iziumova, Aleksei Vshivkov, Ivan Panteleev, Virginia Mubassarova, Oleg Plekhov, Denis Davydov
Summary: The aim of this study was to investigate the correlation between structural, acoustic emission, and thermal characteristics of fatigue crack growth in titanium alloys. Cluster analysis of the acoustic emission signals revealed two different types of signals observed during the fatigue crack development. It was experimentally demonstrated that the stored energy tends to reach an asymptotic value at the final stage of fatigue crack growth and this is correlated with the twinning process intensification in titanium alloy Ti Grade 2. A correlation was assumed between the stages of change in heat flux, the cumulative energy of the first cluster of acoustic emission signals, and the crack length.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
M. Vieira de Carvalho, I. A. Rodrigues Lopes, F. M. Andrade Pires
Summary: This study investigates the numerical challenges of fracture mechanics models within implicit quasi-static frameworks and proposes an instability criterion. The ratio of cohesive to internal power is identified as a crucial factor. Two strategies for handling fracture problems with instabilities are discussed and a comparative assessment is performed. The study also examines more complex material responses, including transformation-induced plasticity effects.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Thomas Duminy, Aurelien Doitrand, Sylvain Meille
Summary: This study conducted in situ wedge splitting tests on millimeter-size PMMA samples and proposed a method to determine the material tensile strength and critical energy release rate using digital image correlation and a full finite element implementation of the coupled criterion.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Xin Chang, Xingyi Wang, Chunhe Yang, Yintong Guo, Yanghui Wan
Summary: The influence of cyclic thermal shock and high-temperature acid etching on the Mode I fracture of shale was investigated in this study. It was found that cyclic thermal shock severely degrades the strength and fracture toughness of shale, while high-temperature acid etching treatment improves the fracture toughness. These findings are valuable for optimizing process parameters to reduce initiation pressure in deep shale formations.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Liaojun Yao, Mingyue Chuai, Zhangming Lyu, Xiangming Chen, Licheng Guo, R. C. Alderliesten
Summary: Methods based on fracture mechanics have been widely used in fatigue delamination growth (FDG) characterization of composite laminates. This study proposes appropriate similitude parameters to represent FDG behavior with different R-ratios.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Zesheng Zang, Zhonghui Li, Yue Niu, Shan Yin
Summary: This study conducted experiments and recorded signals to investigate the fracture behavior and damage evolution characteristics of coal samples. The results showed that as loading proceeds, the stress, electric potential (EP), and acoustic emission (AE) values increase, and EP and AE signals are excited when stress drops. The fracture behavior of coal samples is altered by flaw inclination, and the destruction mode becomes increasingly complicated. The damage evolution characteristics of coal samples can be evaluated and analyzed by defining the coefficient of variation (CV value) of EP and the b value of AE.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Clotilde Berdin, Nathalie Prud'homme
Summary: In this study, zirconia layers with different fractions of tetragonal phase and thicknesses were tested for multi-cracking behavior. Cracks perpendicular to the tensile direction were observed, showing a blunting effect into the substrate. The ratio of crack spacing at saturation to layer thickness decreased as the layer thickness increased. Unit cell modeling was used to establish a relationship between crack spacing and layer strength, which fell within the bounds of Hu and Evans model and was found to be insensitive to the tetragonal zirconia fraction.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Huadong Zhang, Weichen Kong, Y. H. Liu, Yuh J. Chao
Summary: Williams' series expansion crack tip solution in linear elasticity is modified to include a uniform crack face pressure. Practical methods to calculate T-stress from near crack tip stresses are outlined. The analytical results are consistent with numerical results.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Jiahao Kong, Haoyue Han, Tao Wang, Guangyan Huang, Zhuo Zhuang
Summary: This paper introduces a phase-field model for polymer foam materials by combining the phase-field method with the crushable foam model. The model is calibrated using experimental data and successfully simulates the fracture processes of polyurethane under different loading conditions. The study is important for the engineering applications of polymer foam materials.
ENGINEERING FRACTURE MECHANICS
(2024)