Computational Particle Mechanics最新文献

{"title":"Understanding post-impact biomechanics of ballistic cranial injury by smoothed particle hydrodynamics numerical modelling","authors":"Akanae Chattrairat, Everson Kandare, Sontipee Aimmanee, Phuong Tran, Raj Das","doi":"10.1007/s40571-024-00783-2","DOIUrl":"https://doi.org/10.1007/s40571-024-00783-2","url":null,"abstract":"<p>Virtual crime scene investigation using numerical models has the potential to assist in the forensic investigation of firearm-related fatalities, where ethical concerns and expensive resources limit the scope of physical experiments to comprehend the post-impact biomechanics comprehensively. The human cranial numerical model developed in this study incorporates three main components (skin, skull, and brain) with dynamic biomaterial properties. The virtual model provides valuable insights into the post-impact biomechanics of cranial ballistic injuries, particularly in high-speed events beyond conventional investigative capabilities, including the velocity of ejected blood backspatter, cavitation collapsing, and pressure waves. The validation of the numerical model, both quantitatively and qualitatively, demonstrates its ability to replicate similar bone fractures, entrance wound shapes, and backward skin ballooning observed in physical experiments of the human cranial geometry. The model also yields similar temporary cavity sizes, wound sizes, and blood backspatter time against the physical cranial model, aiding in bloodstain pattern analysis. Additionally, the numerical model enables exploration of ballistic factors that vary in each crime scene environment and influence cranial injuries, such as projectile type, velocity, impact location, and impact angle. These established injury patterns contribute to crime scene reconstruction by providing essential information on projectile trajectory, discharge distance, and firearm type, assisting in the resolution of court cases. In conclusion, the developed human cranial geometry in this study offers a reliable tool for investigating firearm-related cranial injuries, serving as a statistical reference in forensic science. Virtual crime scene investigations\u0000using these models\u0000have the potential to enhance the accuracy and efficiency of forensic analyses.</p>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"9 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141505220","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":"Modeling of ultrasonic vibration-assisted micromachining using the particle finite element method","authors":"Hadi Bakhshan,&nbsp;Eugenio Oñate,&nbsp;Josep Maria Carbonell","doi":"10.1007/s40571-024-00791-2","DOIUrl":"10.1007/s40571-024-00791-2","url":null,"abstract":"<div><p>When metals and alloys are exposed to ultrasonic vibrations (UV), a softening behavior occurs, caused by the phenomenon of acousto-plasticity. To obtain accurate results in a deformation analysis, this phenomenon must be included in the formulation of the constitutive material model. In this work, an acoustic-plastic model is proposed to capture the effects of ultrasonic vibrations during machining. The desired effect is to modify the chip morphology to reduce the magnitude of the cutting forces and thus reduce the energy consumption of the process. The study focuses on the modeling of ultrasonic vibration-assisted micromachining (VAMM). The particle finite element method is used and extended to perform a thermo-mechanical analysis capable of capturing the responses of conventional micromachining (CMM) and VAMM operations of 32 HRC stainless steel. The cutting speed and UV parameters, including amplitude and frequency, are integrated into the Johnson–Cook constitutive model to account for the effects of acoustic softening on the machining characteristics. The results show that the influence of UV on microcutting leads to thinner chips and lower cutting force. In the VAMM operations, an average reduction in cutting forces of 20% is achieved at five different cutting speeds. In addition, the contact length between the tool and chip decreases at different cutting speeds from 29% to a maximum of 44%. Furthermore, the thermal analysis results show that there is a negligible temperature change during the CMM and VAMM simulations, indicating that the study of the machining process can focus exclusively on its mechanical aspects when performed at the microscale. The predicted average chip thickness and effective shear angle of the workpiece material are in strong agreement with the experimental results, emphasizing the importance of considering acoustic softening in VAMM studies.</p></div>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"11 5","pages":"2267 - 2290"},"PeriodicalIF":2.8,"publicationDate":"2024-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141505217","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":"Determination and parameters calibration of the soybean-bonded particle model based on discrete element method","authors":"Dan-Dan Han, Qing Wang, Yun-Xia Wang, Wei Li, Chao Tang, Xiao-Rong Lv","doi":"10.1007/s40571-024-00792-1","DOIUrl":"https://doi.org/10.1007/s40571-024-00792-1","url":null,"abstract":"<p>To determine the desirable bonding parameters of the soybean-bonded particle model for accidentally simulating the working process of a pneumatic soybean seed-metering device. Taking the compressive destructive force (<i>F</i>_c<i>,p</i>) derived from the uniaxial compression test of soybean seeds as the evaluation index for the compression simulation tests. The Plackett–Burman and the steepest ascent tests were executed to identify the centroids of the influential factors that substantially affect the bonding force of the soybean-bonded particle model. The optimal values of the significance influencing variables were determined based on the Box–Behnken response surface test. The results indicated that the effect of bonded disk radius (<i>R</i>_B<i>,p</i>) between fraction particles on the <i>F</i>_c<i>,p</i> was extremely significant, and the effects of the restitution coefficient (<i>e</i>_p-steel) and static friction coefficient (<i>μ</i>_p-steel) of soybean-steel, normal stiffness per unit area (<i>k</i>_n<i>,p</i>) and critical normal stress (<i>σ</i>_max<i>,p</i>) were found to be statistically significant. The preferred values identified by Box–Behnken response surface test were 0.520 for <i>e</i>_p-steel, 0.274 for <i>μ</i>_p-steel, 4.082 × 10⁷ N/m³ for <i>k</i>_n<i>,p</i>, 3.517 × 10⁵ Pa for <i>σ</i>_max<i>,p</i>, and 0.982 mm for <i>R</i>_B<i>,p</i>, respectively. The compressive destructive force of soybean seeds was 211.32 N at this point, which was 0.2% less than the measured value of 211.74 N. The results of comparing the grain morphologies during the actual and simulated compressions indicated that the compression states had a superior consistency. It was determined that the DEM simulation input parameters for the soybean-bonded particle model calibrated were proven to be effective and dependable. The investigation presented in this paper can be utilized to effectively analyze the working process of the pneumatic soybean seed-metering devices through coupled simulation. It can also serve as a reference for other researchers to construct a particle model for DEM simulation using the BPM approach.</p>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"151 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141505218","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 moving least square immersed boundary method for SPH with thin-walled rigid structures","authors":"Zhuolin Wang,&nbsp;Zichao Jiang,&nbsp;Yi Zhang,&nbsp;Gengchao Yang,&nbsp;Trevor Hocksun Kwan,&nbsp;Yuhui Chen,&nbsp;Qinghe Yao","doi":"10.1007/s40571-024-00721-2","DOIUrl":"10.1007/s40571-024-00721-2","url":null,"abstract":"<div><p>This paper presents a novel method for smoothed particle hydrodynamics (SPH) with thin-walled rigid structures. Inspired by the direct forcing immersed boundary method, this method employs a moving least square method for the velocity interpolation instead of the linear interpolation. It reduces oscillations due to changing relative positions between fluid grids and structures. It also simplifies thin-walled rigid structure simulations by eliminating the need for multiple layers of boundary particles, and improves computational accuracy and stability in three-dimensional scenarios. Results of the impulsively started plate test demonstrate that the proposed method obtains smooth velocity and pressure, as well as a good match to the references results of the vortex wake development. Results of the flow past cylinder test show that the proposed method avoids mutual interference on both side of the boundary, while accurately calculating the forces acting on structure. By comparing to linear least square direct forcing scheme and the diffusive direction scheme, advantages of lower oscillation and higher accuracy are proven. Results of flow past a sphere further indicate the stability of the proposed method for three-dimensional simulations.\u0000</p></div>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"11 5","pages":"1981 - 1995"},"PeriodicalIF":2.8,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141505219","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":"Influence of intermediate principal stress and rolling resistance on the shearing response of sand: a micromechanical investigation","authors":"S. V. Dharani Raj, Mousumi Mukherjee, Andres Alfonso Peña-Olarte, Roberto Cudmani","doi":"10.1007/s40571-024-00782-3","DOIUrl":"https://doi.org/10.1007/s40571-024-00782-3","url":null,"abstract":"<p>Existing literature on true triaxial and torsional shear tests indicate that the mechanical response of a granular assembly is significantly influenced by the magnitude of the intermediate principal stress ratio. The present study aims to explore the mechanism behind such effects in reference to the particle-level interaction using 3D DEM simulations. In this regard, true triaxial numerical simulations have been carried out with constant minor principal stress and varying <span>(b)</span> values employing rolling resistance-type contact model to mimic particle shape. The numerical simulations have been validated against the true triaxial experiments reported in the literature for dense Santa Monica beach sand. The macro-level shearing response of the granular assembly has been examined in terms of the evolution of stress ratio and volumetric strain for different rolling resistance coefficients. Further, such macro-level response has been assessed in reference to the micro-scale attributes, e.g. average contact force, number of interparticle contacts, mechanical coordination number, contact normal orientation, and fabric tensor as well as meso-scale attribute like strong contact force network. Lade’s failure surface has been adopted to represent the stress and fabric at peak state in the octahedral plane, and mathematical expressions have been proposed relating the failure surface parameters to the rolling resistance coefficient.</p><h3 data-test=\"abstract-sub-heading\">Graphical abstract</h3>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"14 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141505221","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":"Efficient explicit time integration algorithms for non-spherical granular dynamics on group S(3)","authors":"Zonglin Li, Ju Chen, Qiang Tian, Haiyan Hu","doi":"10.1007/s40571-024-00780-5","DOIUrl":"https://doi.org/10.1007/s40571-024-00780-5","url":null,"abstract":"<p>Discrete element method (DEM) is a powerful tool for the dynamic simulation of irregular non-spherical particle systems. The efficient integration of the rotational motions of numerous particles in DEM poses a big challenge. This paper presents six explicit time integration algorithms, comprising three first-order algorithms and three second-order algorithms, for the rotational motions of non-spherical particles based on the theory of unit quaternion group S(3). The proposed algorithms based on Cayley map do not contain any transcendental function and have high efficiency. The numerical examples underscore the superiority of the first-order symplectic Euler Cayley algorithm (SECay) and the second-order central difference Cayley algorithm (CDCay) in terms of both efficiency and accuracy. In the testing cases of granular systems, SECay and CDCay demonstrate approximately 80% reduction in computational time for the time integration part, compared to the improved predictor–corrector direct multiplication method (IPCDM). Therefore, SECay and CDCay emerge as promising tools for non-spherical DEM simulations.</p>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"18 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141505223","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":"Assessing the effect of layered spatial variability on soil behavior via DEM simulation","authors":"De-Yun Liu, Han-qiao Che, Ci Wang, Yuan Chen","doi":"10.1007/s40571-024-00779-y","DOIUrl":"https://doi.org/10.1007/s40571-024-00779-y","url":null,"abstract":"<p>Motivated by the spatial variability observed in geological profiles, this study explored the feasibility of using discrete element method (DEM) to capture the effect of layered spatial variability into overall soil performance. The spatial variability of packing densities, particle Young’s modulus (<i>E</i>), and frictional properties (<i>μ</i>) within specimens was studied. It was observed that samples with similar overall void ratios exhibited comparable small-strain stiffness and shearing behaviors. In contrast, the coordination number and particle stress transmission demonstrated significant sensitivity to the layer-wise spatial variability in packing densities. Regarding the spatial variability effect of particle-scale <i>E</i> values, this study illustrates that spatial variability strongly affects the stiffness contributions of individual layers. Specifically, layers with higher <i>E</i> values are capable of transferring much stress and stiffness. For the spatial variability effect of frictional property, a degree of consistency in shearing behaviors was observed among specimens with similar average frictional characteristics, while layers with lower frictional property were identified as potential initial failure junctures. Overall, this study validates the utility of employing a DEM code for analyzing both the macroscopic behavior and localized vulnerabilities within complex granular systems, presenting profound implications for engineering practices.</p>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"27 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141505222","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":"The effect of particle shape on the dynamics of spherical projectile impacting into granular media","authors":"Xingli Zhang,&nbsp;Honghua Zhao,&nbsp;Yifan Wang,&nbsp;Dashuai Zhang,&nbsp;Yuntian Bai","doi":"10.1007/s40571-024-00745-8","DOIUrl":"10.1007/s40571-024-00745-8","url":null,"abstract":"<div><p>To investigate the effect of particle shape on the dynamics of projectile impact into granular media, this study conducted discrete element method (DEM) numerical simulation using Particle Flow Code (PFC) software. Three particle shapes of granular materials were selected, where spherical particles represented by ball elements, ellipsoidal particles and irregular particles generated by clumps according to a certain template profile. The microscopic contact parameters were calibrated by laboratory tests and numerical simulations of standard direct shear tests. On this basis, the DEM model of a spherical projectile impact into the granular bed was established and laboratory tests were conducted. The test data matched well with the numerical results, verifying the reasonableness and accuracy of the numerical model. Analysing the results by varying the parameters shows that the impact process can be divided into three stages: impact, penetration and collapse. The particle shape does not affect the final penetration depth of the projectile as a power-law function of the initial velocity, and all follow the generalised Poncelet law. The difference in the peak impact force indicates that non-spherical particles have better cushioning capacity, and the analysis of the energy evolution during impact shows that there is significant variability in the effect of particle shape on the energy dissipation of the system. Finally, the internal response of the granular media during the impact process is elucidated by the results of porosity and coordination number. The force chains of granular materials undergo fracture and recombination during the impact process, and the particle shape significantly affects the structural distribution and evolution of the force chains.</p></div>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"11 6","pages":"2677 - 2692"},"PeriodicalIF":2.8,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141373551","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":"Easily porting material point methods codes to GPU","authors":"Edward Buckland,&nbsp;Vinh Phu Nguyen,&nbsp;Alban de Vaucorbeil","doi":"10.1007/s40571-024-00768-1","DOIUrl":"10.1007/s40571-024-00768-1","url":null,"abstract":"<div><p>The material point method (MPM) is computationally costly and highly parallelisable. With the plateauing of Moore’s law and recent advances in parallel computing, scientists without formal programming training might face challenges in developing fast scientific codes for their research. Parallel programming is intrinsically different to serial programming and may seem daunting to certain scientists, in particular for GPUs. However, recent developments in GPU application programming interfaces (APIs) have made it easier than ever to port codes to GPU. This paper explains how we ported our modular C++ MPM code <span>Karamelo</span> to GPU without using low-level hardware APIs like CUDA or OpenCL. We aimed to develop a code that has abstracted parallelism and is therefore hardware agnostic. We first present an investigation of a variety of GPU APIs, comparing ease of use, hardware support and performance in an MPM context. Then, the porting process of <span>Karamelo</span> to the Kokkos ecosystem is detailed, discussing key design patterns and challenges. Finally, our parallel C++ code running on GPU is shown to be up to 85 times faster than on CPU. Since Kokkos also supports Python and Fortran, the principles presented therein can also be applied to codes written in these languages.</p></div>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"11 5","pages":"2127 - 2142"},"PeriodicalIF":2.8,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40571-024-00768-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141386489","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":"On the sensitivity of DEM parameters on pile experiments","authors":"Momme Jahn,&nbsp;Martin Meywerk","doi":"10.1007/s40571-024-00769-0","DOIUrl":"10.1007/s40571-024-00769-0","url":null,"abstract":"<div><p>The discrete element method (DEM) is suitable to investigate problems where large deformations occur especially in granular material. The fitting of reliable DEM parameters is crucial and a challenge which is caused by the high number of DEM parameters and the computational effort. Despite its drawbacks, a trial and error approach is often used for the DEM parameter calibration. The knowledge of the DEM parameter influence on the model response is necessary to improve the calibration and to check whether the experiment is suitable to calibrate specific parameters or not. It is possible to reduce the dimensionality of the optimisation problem by omitting parameters whose influence on the model response is negligibly small. One approach is to perform a global sensitivity analysis based on Sobol’ indices. A frequently used calibration experiment in literature is the pile experiment. The deviation between the experiment and the simulation is evaluated with the angle of repose. In the present paper, an algorithm to determine the angle of repose considering the three-dimensional shape of the heap is discussed. The global sensitivity analysis is performed for two different experimental heap set-ups. To decrease the computational effort of the sensitivity analysis, the model response is approximated with metamodels whose predictability is evaluated using the root mean squared error (RMSE) based on a separate sampling point set.</p></div>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":"11 6","pages":"2971 - 2993"},"PeriodicalIF":2.8,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40571-024-00769-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141255765","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}