Computational Particle Mechanics最新文献

{"title":"Multiscale analysis of elastodynamics of graphene-embedded ceramic composite plates","authors":"Mohammad Reza Talebi Bidhendi, Kamran Behdinan","doi":"10.1007/s40571-024-00828-6","DOIUrl":"https://doi.org/10.1007/s40571-024-00828-6","url":null,"abstract":"<p>The performance of graphene–silicon carbide (SiC) composite multilayered structure under various transverse impact loading conditions is considered in this paper. This prototypical system is examined using a multiscale approach which integrates ReaxFF molecular dynamics with Reddy’s third-order shear deformation plate theory in a hierarchical framework. In essence, the developed multiscale analysis combines the simulation of material properties (i.e., graphene nanofiller and the ceramic matrix) at the atomic scale and the mechanics of the structure at the macroscale. Accordingly, the governing equations of the aforementioned system are discretized and solved by utilizing a meshfree method. In that regard, the elastodynamics of such composites is characterized by factoring in constituent materials properties and nanofiller volume fraction. Comprehensive numerical simulations, corroborated by some of the available experimental evidence from the existing reports, reveal that (a) oxidation degree of the graphene nanofiller can be introduced as a novel tuning factor for the elastodynamic response of the macroscale graphene–ceramic composite structures, and (b) higher volume fraction of graphene enhances the flexibility and induces larger deflection of the composite plate under various dynamic loadings (softening effect). Furthermore, the dependency of the results on the structural boundary conditions is assessed. The multiscale approach and findings of this study offer insights into the feasible bottom-up design pathways for developing novel multilayered ceramic matrix composites with graphene inclusion for applications in structural engineering, energy devices, and aerospace industries.</p>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"84 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DEM meso-damage analysis for double-block ballastless track with non-coincident interlayer contact","authors":"Jiajun He, Weixing Liu, Chang Xu, Tianci Xu, Zhixuan Wang, Pingrui Zhao","doi":"10.1007/s40571-024-00824-w","DOIUrl":"https://doi.org/10.1007/s40571-024-00824-w","url":null,"abstract":"<p>Interlayer cracking has become a major defect in ballastless tracks, and the uniaxial compression behavior and damage under non-coincident interlayer contact have become a key research focus to support service performance. This study establishes a discrete element model for the non-coincident interlayer contact of composite specimens of double-block ballastless track under normal loads. The normal load–displacement curve was obtained, and the meso-damage characteristics with non-coincident interlayer contact were investigated. By analyzing the changes in force chains and crack propagation during the loading process, the damage mechanism of non-coincident interlayer contact is clarified. The influence of roughness on the damage behavior of composite specimens under non-coincident interlayer contact is also discussed. The results show that: 1) The normal displacement increases nonlinearly under normal loads, and during the loading process, the bonding between particles on the rough interface breaks, leading to a sudden drop in load; 2) there is a linear relationship between the number of cracks and displacement in the interlayer region, while in the matrix region, the relationship is stage-dependent. During the stage where damage occurs in both the interlayer interface and matrix, the matrix begins to fail, with 83% of all cracks appearing in this stage; 3) there is a correlation between the force chain and the development of damage in the specimens. When interlayer spalling occurs, shear cracks dominate; when the matrix begins to crack and penetrate, tensile cracks dominate; and 4) the peak strength of specimens with non-coincident interlayer contact and <i>R</i>_a follows an exponential function relationship. As roughness increases, the failure mode of the specimens shifts from primarily matrix cross-penetration to primarily interlayer material spalling. Additionally, the proportion of cracks in the interlayer region relative to the total gradually increases. The results of this study will contribute to a deeper understanding of the damage mechanism after interlayer cracking in ballastless tracks, particularly the damage evolution characteristics at the mesoscopic level.</p>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"107 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Four-dimensional lattice spring model for blasting vibration of tunnel surrounding rock","authors":"Xuxin Chen, Xiao Wang, Chuanyang Jia, Vahab Sarfarazi","doi":"10.1007/s40571-024-00822-y","DOIUrl":"https://doi.org/10.1007/s40571-024-00822-y","url":null,"abstract":"<p>Four-dimensional lattice spring model (4D-LSM) has the intrinsic advantage of analyzing the large dynamic problem. It has better adaptability to the dynamic response of tunnel blasting excavation. The 4D-LSM model of the vibration in small-distance tunnel blasting is established. The dynamic response of the surrounding rock was analyzed by applying the nonreflective boundary condition and equivalent explosive load. The results show that the blasting vibration waves and the air pressure waves generated by tunnel blasting excavation are attenuated to the outside in the form of column surface wave. Due to the cavity effect of the blasting vibration, the vibration wave was reflected at the boundary of the neighboring tunnel contour. The peak particle velocity (PPV) of the rock sandwich area in the small clear-distance tunnel decreases with the increase in blasting distance. The blasting vibration wave was reflected by blasting cavity effect. It causes the increase in the peak particle velocity (PPV) of the surrounding rock mass in the local zone.</p>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"35 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A calibration framework for DEM models based on the stress‒strain curve of uniaxial compressive tests by using the AEO algorithm and several calibration suggestions","authors":"Min Wang, Zhenxing Lu, Yanlin Zhao, Wen Wan","doi":"10.1007/s40571-024-00820-0","DOIUrl":"https://doi.org/10.1007/s40571-024-00820-0","url":null,"abstract":"<p>Before the discrete element method (DEM) is implemented for numerical simulations, the microparameters of the DEM models should be calibrated. Microparameter calibration is a critically important procedure for numerical DEM simulations. The macroparameters obtained from physical tests (e.g. UCS, Young’s modulus, Poisson’s ratio) were used to calibrate the microparameters of DEM models. However, the mechanical characteristics of rock materials cannot be fully reflected by the macroparameters. Hence, in this paper, the stress‒strain relationships of uniaxial compressive tests were used for calibrating the microparameters of DEM (discrete element method) models by using the artificial ecosystem-based optimization (AEO) algorithm, combined with a Python script and a stress‒strain curve of uniaxial compressive tests from laboratory experiments. Additionally, a microparameter calibration framework was proposed. To verify the validity of the proposed method, two examples were evaluated, and the numerical simulation results indicated that the proposed method can be applied to calibrate the microparameters of DEM models. Moreover, to analyse the influence of each microparameter on the stress‒strain curve of uniaxial compressive tests, a large number of numerical simulations were conducted. Finally, based on the analysis, some microparameter calibration suggestions were provided. This study provides a new method for calibrating microparameters and provides calibration suggestions that are critically important for numerical DEM simulations.</p>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"101 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization research on the layout of scouring pipes in the slurry shield based on CFD-DEM simulation","authors":"Han Wang, Minghui Zhang, Menghan Chen, Wantao Ding, Keqi Liu, Chengzhen Wang, Wenduan Yu, Zhicheng Wang","doi":"10.1007/s40571-024-00829-5","DOIUrl":"https://doi.org/10.1007/s40571-024-00829-5","url":null,"abstract":"<p>Slurry shield construction frequently encounters the risk of air cushion chamber clogging, which may cause pipeline damage at a minor level, or serious abnormal shutdown of the shield machine, resulting in serious negative impacts on construction safety and efficiency. Current studies primarily focus on the transport characteristics of cuttings in the discharge pipe, while the complete process from the air cushion chamber into the discharge pipe until discharge is often overlooked. The air cushion chamber is decisive in this process, fundamentally determining the discharge performance of cuttings. Therefore, the reasonable layout of scouring pipes within the chamber is particularly critical for alleviating the clogging risk. However, the current layout of scouring pipes lacks sufficient guidance, necessitating urgent optimization research. This paper establishes a model that more comprehensively reflects the process of cuttings discharge based on the CFD-DEM method and investigates the effects of scouring pipes layout on cuttings discharge performance. The results indicate that the cuttings discharge performance improves with the decrease in the layout height and rotation angle of the scouring pipes, as well as with the increase in the layout width and extension distance. Additionally, the layout scheme of scouring pipes with optimal discharge performance is determined based on the response surface method. These findings contribute to alleviating the risk of clogging in the air cushion chamber of the slurry shield.</p>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"8 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization and prediction of the effects of random factors on buffering efficiency in slope-cushion layer collisions through the discrete element method","authors":"Shao-zhen Duan, Guang-li Li, Xin Yang","doi":"10.1007/s40571-024-00826-8","DOIUrl":"https://doi.org/10.1007/s40571-024-00826-8","url":null,"abstract":"<p>This study developed a numerical model based on the discrete element method to investigate the characteristics of a granular slope-cushion layer during collision. The model considered the influence of cushion particle radius, incidence velocity, cushion thickness, and initial rotational angular velocity. The results indicated that a larger cushion particle radius generated a stronger impact force and a higher percentage increase (up to 34%) in the impact force. The counterclockwise initial angular velocity of the rockfall facilitated the splashing of the cushion particles at the bottom of the slope cushion. The clockwise motion of the rockfall results in its bouncing on the surface of the slope–cushion system. Using the normalization method, the maximum impact force, penetration depth, and energy dissipation ratio were fitted as functions of cushion thickness. The results of this study provide a solid theoretical foundation for the design of slope-cushion layers.</p>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"188 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DEM modelling of surface indentations caused by granular materials: application to wheel–rail sanding","authors":"Bettina Suhr,&nbsp;William A. Skipper,&nbsp;Roger Lewis,&nbsp;Klaus Six","doi":"10.1007/s40571-024-00816-w","DOIUrl":"10.1007/s40571-024-00816-w","url":null,"abstract":"<div><p>The presented surface indentation model is one step towards building a DEM model for wheel–rail sanding. In railways, so-called low-adhesion conditions can cause problems in traction and braking, and sanding is used to overcome this problem. Sand grains are blasted towards wheel–rail contact, fracture repeatedly as they enter the nip and are drawn into the contact and then increase adhesion. Research on this topic has mostly been experimental, but focussed on adhesion enhancement measurement. Thus, physical mechanisms increasing the adhesion are not well understood. Previous works involved experiments and DEM modelling of single sand grain crushing tests under realistic wheel–rail contact pressures of 900 MPa, focusing on sand fragment spread and formation of clusters of solidified fragments. In the experiments, indents in the compressing steel plates were also observed, which are also observed on wheel and rail surfaces in railway operation. These are now modelled by adapting an existing surface indentation model from literature to the case of surface indentations caused by granular materials. Two test cases are studied, and experimental spherical indentation tests for model parametrisation are presented. In a proof of concept, the mentioned single sand grain crushing tests under 900 MPa pressure are simulated including the surface indentation model. This work contributes to DEM modelling of wheel–rail sanding, which is believed to be a good approach to deepen the understanding of adhesion increasing mechanisms under sanded conditions.</p></div>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"11 5","pages":"2353 - 2367"},"PeriodicalIF":2.8,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40571-024-00816-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Constrained particle dynamics","authors":"Cuong T. Nguyen,&nbsp;Suvranu De","doi":"10.1007/s40571-024-00814-y","DOIUrl":"10.1007/s40571-024-00814-y","url":null,"abstract":"<div><p>This paper presents a constrained particle dynamics (CPD) framework with explicit and implicit algorithms for simulating differential–algebraic equations of motion for systems of particles under constraints. Addressing limitations in existing techniques such as position-based dynamics (PBD), commonly used in computer graphics but prone to inaccuracies, the CPD approach utilizes Hamilton’s variational principle and Lagrange multipliers to ensure accurate constraint enforcement. The explicit CPD (xCPD) algorithm employs a central difference scheme, enhancing efficiency by advancing the system under external forces and applying a correction term for constraints. The implicit CPD (iCPD) algorithm uses the Trapezoidal rule, solving a saddle point problem that integrates dynamic and constraint equations, offering robustness for larger time steps. The effectiveness of the CPD algorithms is demonstrated through mathematical analysis and numerical comparisons of benchmark problems. Results indicate that CPD algorithms achieve higher accuracy and superior energy conservation properties compared to PBD, exhibiting second-order convergence rates; whereas, PBD shows only first-order convergence.</p></div>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"11 5","pages":"2307 - 2324"},"PeriodicalIF":2.8,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A volume-adaptive mesh-free model for FSI Simulation of cavitation erosion with bubble collapse","authors":"Qiang Zhang,&nbsp;Xin Liu,&nbsp;Xiangwei Dong,&nbsp;Li Yin,&nbsp;Zhou Cheng","doi":"10.1007/s40571-024-00815-x","DOIUrl":"10.1007/s40571-024-00815-x","url":null,"abstract":"<div><p>Cavitation erosion is a pervasive issue in hydraulic machinery and ocean engineering, characterized by the collapse of bubbles, micro-jetting, and impact erosion, all exhibiting strong transient, microscale, and fluid–solid coupling features. Understanding these phenomena is essential for elucidating the mechanisms behind erosion and for developing strategies to prevent wear damage. Recognizing the limitations of conventional numerical methods, this study employs the smoothed particle hydrodynamics (SPH) method to develop a fluid–solid coupling model that simulates cavitation erosion at the bubble scale. The Lagrangian and mesh-free nature of SPH make it well-suited for tracking the transient processes of asymmetric bubble collapse, jet formation, and the subsequent impact on elastic–plastic materials. A comprehensive fluid–solid coupling SPH model is constructed, encompassing bubbles, surrounding liquids, and elastic–plastic materials. This model includes a compressible multiphase SPH approach for simulating the interaction between highly compressible bubbles and liquids. To address gas phase over-compression during bubble collapse, a modified particle regeneration technique (PRT) is introduced, allowing for automatic adjustment of particle resolution in the gas domain as it expands or compresses. For the solid simulation, an elasto-plastic constitutive model and a failure model are integrated into the SPH framework to describe material deformation and failure due to microjet impacts. These enhancements enable the simulation of the entire cavitation erosion process within a unified, mesh-free context. The SPH model is validated through simulating bubble collapse and jetting induced by shock waves. It is then applied to investigate the dynamics of cavitation erosion near both rigid and elastic–plastic materials, providing quantitative analysis of the erosion process. The outcomes of this research contribute significantly to our understanding of cavitation erosion mechanisms and offer a robust computational tool for predicting and mitigating erosion damage in related engineering applications.</p></div>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"11 5","pages":"2325 - 2351"},"PeriodicalIF":2.8,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mesoscopic damage mechanism of multiple freeze–thaw cycles of cement gravel based on particle flow theory","authors":"Li Zhao, Zhanyou Yan, Shuo Xu, Shuangjiang Ren, Yunjiang Wang, Lei Chi","doi":"10.1007/s40571-024-00819-7","DOIUrl":"https://doi.org/10.1007/s40571-024-00819-7","url":null,"abstract":"<p>Currently, most experts only focus on the surface failure characteristics of material structures. Moreover, previous damage constitutive models were unable to simulate the nonlinear deformation characteristics of cement crushed stone during the initial compaction stage. To study the microdamage of cement crushed stone after freeze–thaw cycles and uniaxial compression, further exploration was conducted on the changes in displacement, number of microcracks, relationship between acoustic emission events and microcrack development after freeze–thaw cement gravel loading, as well as the number of force chains before and after loading. Based on the theory of damage mechanics, this article establishes a damage constitutive model that can simulate the entire deformation process of cement crushed stone under uniaxial compression conditions using a particle flow program. Based on the numerical model created by the discrete element method, this article reproduces the entire process of internal fracture of cement crushed stone from a microscopic perspective, which has certain advantages in studying the complex mechanical behavior of cement crushed stone. After freeze–thaw treatment, irreversible damage occurs inside the cement-stabilized crushed stone. The more freeze–thaw cycles, the lower the compressive strength of cement-stabilized crushed stone.</p>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"10 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}