Journal articles: 'Particle dynamic'

1

Liu, Xueqing, Song Yue, Luyi Lu, Wei Gao, and Jianlan Li. "Numerical Simulations of a Gas–Solid Two-Phase Impinging Stream Reactor with Dynamic Inlet Flow." Energies 11, no. 7 (July 23, 2018): 1913. http://dx.doi.org/10.3390/en11071913.

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Fluid flow characteristics and particle motion behavior of an impinging stream reactor with dynamic inlet flow (both inlet velocity patterns exhibit step variation) are investigated and discussed with the computational fluid dynamics–discrete element method (CFD–DEM). The effect of T (variation period of the dynamic inlet flow) and ∆u (inlet velocity difference) on the motion characteristics of single and multiple particles, as well as the mean particle residence time, are studied and discussed. The research results indicate that, compared with the traditional impinging stream reactor (both inlet velocities are equal and constant) with equal mean inlet velocity (um) within one period, the impinging surface is instantaneously moving and the flow regime is varied with time in the impinging stream reactor with dynamic inlet flow. The impinging stream reactor with dynamic inlet flow provides higher cost performance over the traditional impinging stream reactor, under equal um, in terms of single-particle residence time. Moreover, three new particle motion modes exist in multi-particle motions of the impinging stream reactor with dynamic inlet flow; particles are accelerated by the original or reverse fluid and perform oscillatory motion at least once after an interparticle collision. Whether it is a single particle or multi-particles, the mean particle residence time reaches a maximum value when T/2 is approximately equal to the first particle acceleration time, since the maximum axial kinetic energy increases in every oscillatory motion compared with traditional impinging stream, and the number of oscillatory motions is increasing. The mean residence time of a particle in the impinging stream reactor with a dynamic inlet flow increases with increasing ∆u, since the dynamic inlet conditions and increasing ∆u can continuously supply more energy to particles and thus cause more particles to enter one of the three new modes of particle motion.

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Wang, Wenxu, Damián Marelli, and Minyue Fu. "Dynamic Indoor Localization Using Maximum Likelihood Particle Filtering." Sensors 21, no. 4 (February 5, 2021): 1090. http://dx.doi.org/10.3390/s21041090.

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A popular approach for solving the indoor dynamic localization problem based on WiFi measurements consists of using particle filtering. However, a drawback of this approach is that a very large number of particles are needed to achieve accurate results in real environments. The reason for this drawback is that, in this particular application, classical particle filtering wastes many unnecessary particles. To remedy this, we propose a novel particle filtering method which we call maximum likelihood particle filter (MLPF). The essential idea consists of combining the particle prediction and update steps into a single one in which all particles are efficiently used. This drastically reduces the number of particles, leading to numerically feasible algorithms with high accuracy. We provide experimental results, using real data, confirming our claim.

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Habibi, A., and A. Luciani. "Dynamic particle coating." IEEE Transactions on Visualization and Computer Graphics 8, no. 4 (October 2002): 383–94. http://dx.doi.org/10.1109/tvcg.2002.1044523.

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Ouriemi, Malika, and Petia M. Vlahovska. "Electrohydrodynamics of particle-covered drops." Journal of Fluid Mechanics 751 (June 16, 2014): 106–20. http://dx.doi.org/10.1017/jfm.2014.289.

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AbstractWe experimentally investigate the effect of surface-absorbed colloidal particles on the dynamics of a leaky dielectric drop in a uniform DC electric field. Depending on the particle polarizabilty, coverage and the electrical field intensity, particles assemble into various patterns such as an equatorial belt, pole-to-pole chains or a band of dynamic vortices. The particle structuring changes droplet electrohydrodynamics: under the same conditions where a particle-free drop would be a steady oblate spheroid, the belt can give rise to unsteady behaviours such as sustained drop wobbling or tumbling. Moreover, particle chaining can be accompanied by prolate drop deformation and tip-streaming.

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Malama, Terence, Agripa Hamweendo, and Ionel Botef. "Molecular Dynamics Simulation of Ti and Ni Particles on Ti Substrate in the Cold Gas Dynamic Spray (CGDS) Process." Materials Science Forum 828-829 (August 2015): 453–60. http://dx.doi.org/10.4028/www.scientific.net/msf.828-829.453.

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This paper presents simulation of molecular dynamics for the deposition of Titanium (Ti) and Nickel (Ni) particles on Ti substrate during Cold Gas Dynamic Spray (CGDS) process. The influencing factors of the deposition process, such as particle incident velocity, particle size and particle temperature are taken into consideration. Ti and Ni were selected because of their potential applications in the aerospace, marine and bio-medical industries. CGDS is preferred because it is a state of the art technique by which coatings are created without significant heating of the sprayed powder. In CGDS, particles are accelerated to supersonic velocities using a high speed gas stream. However, there are inherent difficulties in relating particle deposition characteristics with influencing factors of the deposition process. Moreover, there is limited literature on molecular dynamics simulation of CGDS process. For this reason, this paper develops a simulation process for Ti and Ni particles under influence of many factors using molecular dynamics. In this process, particles are allowed to interact for a short time, giving a view of their motion. The trajectories of these particles are determined by numerically solving the Newton's equations of motion for a system of interacting particles, in which the forces between the particles are defined. The results of the simulation process show that higher incident velocities and larger particle sizes result in stronger interface between the particle and the substrate. Further, higher temperatures of the substrate and particles improve the bond strength.

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YU, K. W., G. Q. GU, J. P. HUANG, and J. J. XIAO. "DYNAMIC ELECTRORHEOLOGICAL EFFECTS OF ROTATING PARTICLES: A BRIEF REVIEW." International Journal of Modern Physics B 19, no. 07n09 (April 10, 2005): 1163–69. http://dx.doi.org/10.1142/s0217979205030013.

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Particle rotation leads to a steady-state which is different from the equilibrium state in the absence of rotational motion. The change of the polarization of the particle due to the rotational motion is called the dynamic electrorheological effect (DER). There are three cases to be considered: rotating particles in a dc field, particle rotation due to a rotating field and spontaneous rotation of particle in dc field (Quincke rotation). In the DER of rotating particles, the particle rotational motion generally reduces the interparticle force between the particles. The effect becomes pronounced when the frequency is on the order of the relaxation rate of the surface charges. In the electrorotation of particles, the mutual interaction between approaching particles will change the electrorotation spectrum significantly. The electrorotation spectrum depends strongly on the medium conductivity as well as the conductivity contrast between the particle and the medium. In the collective behaviors of Quincke rotors, the mutual interactions between the individual rotors lead to the assembly of chain-like structures which make an angle with the applied field. This has an implication of a new class of material.

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Temitope Oyinbo, Sunday, and Tien-Chien Jen. "Molecular Dynamics Simulation of Dislocation Plasticity Mechanism of Nanoscale Ductile Materials in the Cold Gas Dynamic Spray Process." Coatings 10, no. 11 (November 10, 2020): 1079. http://dx.doi.org/10.3390/coatings10111079.

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The dislocation plasticity of ductile materials in a dynamic process of cold gas spraying is a relatively new research topic. This paper offers an insight into the microstructure and dislocation mechanism of the coating using simulations of molecular dynamics (MD) because of the short MD simulation time scales. The nano-scale deposition of ductile materials onto a deformable copper substrate has been investigated in accordance with the material combination and impact velocities in the particle/substrate interfacial region. To examine the jetting mechanisms in a range of process parameters, rigorous analyses of the developments in pressure, temperature, dislocation plasticity, and microstructure are investigated. The pressure wave propagation’s critical function was identified by the molecular dynamics’ simulations in particle jet initiation, i.e., exterior material flow to the periphery of the particle and substrate interface. The initiation of jet occurs at the point of shock waves interact with the particle/substrate periphery and leads to localization of the metal softening in this region. In particular, our findings indicate that the initial particle velocity significantly influences the interactions between the material particles and the substrate surface, yielding various atomic strain and temperature distribution, processes of microstructure evolution, and the development of dislocation density in the particle/substrate interfacial zone for particles with various impact velocities. The dislocation density in the particle/substrate interface area is observed to grow much more quickly during the impact phase of Ni and Cu particles and the evolution of the microstructure for particles at varying initial impact velocities is very different.

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Stratmann, F., E. Herrmann, T. Petäjä, and M. Kulmala. "Modelling Ag-particle activation and growth in a TSI WCPC model 3785." Atmospheric Measurement Techniques Discussions 2, no. 5 (September 25, 2009): 2217–39. http://dx.doi.org/10.5194/amtd-2-2217-2009.

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Abstract. In this work, we modelled activation and growth of silver particles in the water-operated TSI model 3785 water condensation particle counter (WCPC). Our objective was to investigate theoretically how various effects influence the counting efficiency of this CPC. Coupled fluid and particle dynamic processes were modelled with the computational fluid dynamics (CFD) code FLUENT in combination with the Fine Particle Model (FPM) to obtain profiles of temperature, vapour concentration, nucleation rate, and particle size. We found that the counting efficiency of the TSI 3785 for small particles might be affected by the presence of larger particles. Moreover, homogeneous nucleation processes can significantly influence counting efficiency.

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Stratmann, F., E. Herrmann, T. Petäjä, and M. Kulmala. "Modelling Ag-particle activation and growth in a TSI WCPC model 3785." Atmospheric Measurement Techniques 3, no. 1 (February 25, 2010): 273–81. http://dx.doi.org/10.5194/amt-3-273-2010.

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Abstract. In this work, we modelled activation and growth of silver particles in the water-operated TSI model 3785 water condensation particle counter (WCPC). Our objective was to investigate theoretically how various effects influence the counting efficiency of this CPC. Coupled fluid and particle dynamic processes were modelled with the computational fluid dynamics (CFD) code FLUENT in combination with the Fine Particle Model (FPM) to obtain profiles of temperature, vapour concentration, nucleation rate, and particle size. We found that the counting efficiency of the TSI 3785 for small particles might be affected by the presence of larger particles. Moreover, homogeneous nucleation processes can significantly influence counting efficiency.

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Kok, S., and J. A. Snyman. "A Strongly Interacting Dynamic Particle Swarm Optimization Method." Journal of Artificial Evolution and Applications 2008 (March 31, 2008): 1–9. http://dx.doi.org/10.1155/2008/126970.

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A novel dynamic interacting particle swarm optimization algorithm (DYN-PSO) is proposed. The algorithm can be considered to be the synthesis of two established trajectory methods for unconstrained minimization. In the new method, the minimization of a function is achieved through the dynamic motion of a strongly interacting particle swarm, where each particle in the swarm is simultaneously attracted by all other particles located at positions of lower function value. The force of attraction experienced by a particle at higher function value due to a particle at a lower function value is equal to the difference between the respective function-values divided by their stochastically perturbed position difference. The resultant motion of the particles under the influence of the attracting forces is computed by solving the associated equations of motion numerically. An energy dissipation strategy is applied to each particle. The specific chosen force law and the dissipation strategy result in the rapid collapse (convergence) of the swarm to a stationary point. Numerical results show that, in comparison to the standard particle swarm algorithm, the proposed DYN-PSO algorithm is promising.

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Durlofsky, Louis J., and John F. Brady. "Dynamic simulation of bounded suspensions of hydrodynamically interacting particles." Journal of Fluid Mechanics 200 (March 1989): 39–67. http://dx.doi.org/10.1017/s0022112089000558.

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A general method for computing the hydrodynamic interactions among an infinite suspension of particles immersed between two infinite plane boundaries, under the condition of vanishing particle Reynolds number, is presented. The method accounts for both near-field particle-particle and particle-boundary lubrication effects as well as dominant many-body effects, which include reflections with both particles and boundaries. Through relative motion of the boundaries, a bulk shear flow can be generated, and the resulting particle motions, as well as the forces exerted by the boundaries on the fluid, computed. Knowledge of the boundary forces allows for the calculation of the suspension viscosity. The simulation method is applied to several example problems; in one, the resuspension of a sediment layer of particles is illustrated. The general method can also be extended to dynamically simulate suspensions immersed in a pressure driven flow between two walls or through a tube.

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Arinchev, S. V. "Modelling the Dynamics of Wetting of an Absolutely Rigid Tank Using the Particles Method." Proceedings of Higher Educational Institutions. Маchine Building, no. 03 (720) (March 2020): 64–74. http://dx.doi.org/10.18698/0536-1044-2020-3-64-74.

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This work examines a model consisting of two systems of particles, those of liquid and of a tank wall. The tank is not deformed, and its particles are stationary. The liquid particles move in a plane under the action of forces. Each liquid particle interacts with each tank wall particle. The system of liquid particles “wets” the surface of the tank if it is close enough to the system of tank wall particles. The norm of proximity of the two systems is called the degree of wetting. A dynamic process of the liquid particle transfer from the initial to the final state is studied in this work. In the initial state, the system of liquid particles is arbitrarily positioned relative to the particles of the tank wall. In the final state, liquid particles transfer to the nearest neighbourhood of the tank wall particle system and “wet” it. The problem is considered in a two-dimensional formulation. The particle is a material point with a set power characteristic, and a liquid particle is associated with a drop. The analysis of the transfer process is a droplet dynamics problem. The equations of dynamics of the liquid particles are integrated using Runge-Kutta method. The solution converges quickly with regard to particle numbers.

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Martínez-Villegas, Israel, Alma G. Mora-García, Haideé Ruiz-Luna, John McKelliget, Carlos A. Poblano-Salas, Juan Muñoz-Saldaña, and Gerardo Trápaga-Martínez. "Swirling Effects in Atmospheric Plasma Spraying Process: Experiments and Simulation." Coatings 10, no. 4 (April 15, 2020): 388. http://dx.doi.org/10.3390/coatings10040388.

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Experimental evidence of swirling effects in 3D trajectories of in-flight particles is presented based on static and dynamic footprints analysis as a function of stand-off distance of Al2O3 deposited employing a Metco-9MB torch. Swirling effects were validated with a proprietary computational fluid dynamics (CFD) code that considers an argon-hydrogen plasma stream, in-flight particles trajectories, both creating the spray cone, and particle impact to form a footprint on a fixed substrate located at different distances up to 120 mm. Static and dynamic footprints showed that swirl produces a slight deviation of individual particle trajectories and thus footprint rotation, which may affect coating characteristics.

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Lavialle, Olivier, Franck Angella, Christian Germain, and Pierre Baylou. "DYNAMIC PARTICLE SYSTEMS FOR OBJECT STRUCTURE EXTRACTION." Image Analysis & Stereology 22, no. 1 (May 3, 2011): 35. http://dx.doi.org/10.5566/ias.v22.p35-42.

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A new deformable model based on the use of a particle system is introduced. By defining the local behavior of each particle, the system behaves as an active contour model showing a variable topology and regularization properties. The efficiency of the particle system is illustrated by two applications: the first one concerns the use of the system as a skeleton extractor based on the propagation of particles inside a treeshaped object. Using this method, it is possible to generate a cartography of structures such as veins or channels. In a second illustration, the system avoids the problem of initialization of a piecewise cubic Bspline network used to straighten curved text lines.

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Kunze, Miles, Toni Feißel, Valentin Ivanov, Thomas Bachmann, David Hesse, and Sebastian Gramstat. "Analysis of TRWP Particle Distribution in Urban and Suburban Landscapes, Connecting Real Road Measurements with Particle Distribution Simulation." Atmosphere 13, no. 8 (July 30, 2022): 1204. http://dx.doi.org/10.3390/atmos13081204.

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This article deals with methods and measurements related to environmental pollution and analysis of particle distribution in urban and suburban landscapes. Therefore, an already-invented sampling method for tyre road wear particles (TRWP) was used to capture online emission factors from the road. The collected particles were analysed according to their size distribution, for use as an input for particle distribution simulations. The simulation model was a main traffic intersection, because of the high vehicle dynamic related to the high density of start–stop manoeuvres. To compare the simulation results (particle mass (PM) and particle number (PN)) with real-world emissions, measuring points were defined and analysed over a measuring time of 8 h during the day. Afterwards, the collected particles were analysed in terms of particle shape, appearance and chemical composition, to identify the distribution and their place of origin. As a result of the investigation, the appearance of the particles showed a good correlation to the vehicle dynamics, even though there were a lot of background influences, e.g., resuspension of dust. Air humidity also showed a great influence on the recorded particle measurements. In areas of high vehicle dynamics, such as heavy braking or accelerating, more tyre and brake particles could be found.

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Marsh, C. A., G. Backx, and M. H. Ernst. "Static and dynamic properties of dissipative particle dynamics." Physical Review E 56, no. 2 (August 1, 1997): 1676–91. http://dx.doi.org/10.1103/physreve.56.1676.

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Vinokurova, V. D., N. N. Rozanov, and E. G. Fedorov. "On the particle dynamics in a dynamic billiard." Technical Physics 61, no. 7 (July 2016): 965–70. http://dx.doi.org/10.1134/s106378421607029x.

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Cupelli, Claudio, Björn Henrich, Thomas Glatzel, Roland Zengerle, Michael Moseler, and Mark Santer. "Dynamic capillary wetting studied with dissipative particle dynamics." New Journal of Physics 10, no. 4 (April 10, 2008): 043009. http://dx.doi.org/10.1088/1367-2630/10/4/043009.

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Shim, V. P. W., Y. B. Guo, H. W. Gu, and Xu Li. "Response of Silica-Nylon6 Nanocomposites to Static and Dynamic Loading." Materials Science Forum 706-709 (January 2012): 786–92. http://dx.doi.org/10.4028/www.scientific.net/msf.706-709.786.

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Silica-nylon6 composites were fabricated using two types of silica nanoparticle fillers with different surface modifications. Type A particles (treated with hexamethyldisilazane) were uniformly dispersed but only displayed weak long-range interaction with the nylon6 matrix; in contrast, type B particles (modified with 3-aminopropyltriethoxysilane) formed covalent bonds with the nylon6 chains but their dispersion is not good. The silica-nylon6 composites synthesized were subjected to quasi-static and dynamic tension to study the effects of strain rate and nanoparticle fraction. Results show that compared to quasi-static loading, both pure nylon6 and the composites exhibit a higher strength but lower ductility under dynamic loading. With respect to the influence of the nanoparticles, both particle types cause an increase in the elastic modulus and tensile strength. The effect of the two particles on ductility differs – particle A reduces ductility, while particle B decreases ductility under quasi-static loading but enhances it noticeably for dynamic loading. Particle B enhances the mechanical properties more significantly, especially in terms of ductility. These results suggest that ensuring strong particle-matrix bonding is more crucial than good particle dispersion.

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Li, Wei, Cisong Shi, Qing Xu, and Ying Huang. "Dynamic Population Cooperative." International Journal of Swarm Intelligence Research 13, no. 1 (January 1, 2022): 1–20. http://dx.doi.org/10.4018/ijsir.313664.

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Particle swarm optimization (PSO) has attracted wide attention in the recent decade. Although PSO is an efficient and simple evolutionary algorithm and has been successfully applied to solve optimization problems in many real-world fields, premature maturation and poor local search capability remain two critical issues for PSO. Therefore, to alleviate these disadvantages, a dynamic population cooperative particle swarm optimization for global optimization problems (DPCPSO) is proposed. Firstly, to enhance local search capability, an elite neighborhood learning strategy is constructed by leveraging information from elite particles. Meanwhile, to make the particle easily jump out of the local optimum, a crossover-mutation mechanism is utilized. Finally, a dynamic population partitioning mechanism is designed to balance exploration and exploitation capabilities. 16 classic benchmark functions and 1 real-world optimization problem are used to test the proposed algorithm against with 6 typical PSO algorithms. The experimental results show that DPCPSO is statistically and significantly better than the compared algorithms for most of the test problems. Moreover, the convergence speed and convergence accuracy of DPCPSO are also significantly improved. Therefore, the algorithm is highly competitive in solving global optimization problems.

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Ji, Shi Ming, Ya Qi Shen, Li Zhang, Ming Sheng Jin, and Yin Dong Zhang. "Research of the Dynamic Abrasive Particles Field." Key Engineering Materials 407-408 (February 2009): 569–72. http://dx.doi.org/10.4028/www.scientific.net/kem.407-408.569.

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In this paper, a critical study into the dynamic form of abrasive particles through polishing are made, which are under “inconsistent curvature contact” status. In this system, some abrasive particles are colored up and mixed with ordinary ones, by utilizing transparent working surface and stroboscopic light as well; motion state of abrasive particles can be photographed by high speed shot technology. This method can get serials of images while polishing. By using digital image processing technology, distribution of abrasive particle field can be obtained finally. In this paper, the abrasive particles field is researched to obtain the perfect abrasive particle field after purposefully control. Then the influence of the removed material caused by abrasive particles field can be improved, so it can provide strong theory foundation and practice guidance to surface polishing practice.

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Climent, Eric, Kyongmin Yeo, Martin R. Maxey, and George E. Karniadakis. "Dynamic Self-Assembly of Spinning Particles." Journal of Fluids Engineering 129, no. 4 (October 18, 2006): 379–87. http://dx.doi.org/10.1115/1.2436587.

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This paper presents a numerical study of the dynamic self-assembly of neutrally buoyant particles rotating in a plane in a viscous fluid. The particles experience simultaneously a magnetic torque that drives their individual spinning motion, a magnetic attraction toward the center of the domain, and flow-induced interactions. A hydrodynamic repulsion balances the centripetal attraction of the magnetized particles and leads to the formation of an aggregate of several particles that rotates with a precession velocity related to the inter-particle distance. This dynamic self-assembly is stable (but not stationary) and the morphology depends on the number of particles. The repulsion force between the particles is shown to be the result of the secondary flow generated by each particle at low but nonzero Reynolds number. Comparisons are made with analogous experiments of spinning disks at a liquid–air interface, where it is found that the variation in the characteristic scales of the aggregate with the rotation rate of individual particles are consistent with the numerical results.

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Li, Yangliang, Chao Shen, Li Shao, and Yujun Zhang. "Dynamic image acquisition and particle recognition of laser-induced exit surface particle ejection in fused silica." Chinese Optics Letters 17, no. 10 (2019): 101402. http://dx.doi.org/10.3788/col201917.101402.

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Lili Liu, Shengxiang Yang, and Dingwei Wang. "Particle Swarm Optimization With Composite Particles in Dynamic Environments." IEEE Transactions on Systems, Man, and Cybernetics, Part B (Cybernetics) 40, no. 6 (December 2010): 1634–48. http://dx.doi.org/10.1109/tsmcb.2010.2043527.

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Kurzhals, Anja, Katharina Wulf, Volkmar Senz, Thomas Eickner, Niels Grabow, and Wolfram Schmidt. "Determination of Infusion Filter Efficiency applying Dynamic Light Scattering." Current Directions in Biomedical Engineering 8, no. 2 (August 1, 2022): 485–88. http://dx.doi.org/10.1515/cdbme-2022-1124.

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Abstract Filter membranes (pore size 0.2 μm) are frequently used to perform a sterile filtration. To characterize the pore size of filter membranes, a method to determine the particle retention of nanoparticles was defined. The Dynamic Light Scattering method was first analysed and calibrated to correlate the particle concentration with absolute intensity of scattered light. Afterwards, standard particle suspensions with particle sizes of 0.150 μm and 0.239 μm were lead through an infusion filter and the particle retention of the filter was evaluated by the determination of the original and the filtrated particle concentration. The test filter retained 91% of the smaller and 98% of the larger particles. Evaluating the particle retention with Dynamic Light Scattering could be a time saving method with lesser effort compared to existing methods.

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von Gladiss, Anselm, Matthias Graeser, Kerstin Lüdtke-Buzug, and Thorsten M. Buzug. "Contribution of brownian rotation and particle assembly polarisation to the particle response in magnetic particle spectrometry." Current Directions in Biomedical Engineering 1, no. 1 (September 1, 2015): 298–301. http://dx.doi.org/10.1515/cdbme-2015-0074.

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AbstractThe spectrometry of super-paramagnetic iron-oxide nanoparticles is a central tool for characterising particles that are used in Magnetic Particle Imaging. In Magnetic Particle Imaging, nanoparticles are excited by a magnetic field and the particle response is measured. Until now, the influence of the trajectory sequence on the dynamic particle relaxation has not been scoped. With a multi-dimensional Magnetic Particle Spectrometer, analysing the behaviour of different trajectories on the particles becomes possible. In this paper, the contribution of Brownian rotation and assembly polarisation on the particle signal is being analysed.

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Ping, An, Jian Wang, Ruofan Xiao, Renying Liu, Yanan Chang, and Qingmin Li. "Trap Parameters Optimization Based on Metal Particle Dynamic Simulation Method." Symmetry 14, no. 6 (June 9, 2022): 1187. http://dx.doi.org/10.3390/sym14061187.

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Insulation failure usually occurs in AC gas-insulated transmission (AC GIL) in field operation, in which the primary cause is the charged motion of metal particles in the electric filed. At present, the particle inhibition method applied is to design particle traps on the inner wall of the GIL shell. However, due to the large randomness of the charged motion for metallic particles and the limitations of field test methods, a particle trap has not yet been designed from the perspective of particle trapping effectiveness. In this paper, firstly, referring to the size of a running 252 kV AC GIL, a 1:1 scaled 3-D similarity simulation model is established to obtain the dynamic characteristics of particles with different sizes under the operating voltage level. This model can form symmetry between the real equipment, and its simulated simulation trajectory can achieve symmetry with the actual one. Secondly, an experimental platform that can easily capture the motion of the particles is set up to experimentally verify the symmetry between the field operating equipment and the simulation model. Finally, the particle traps are set on both sides of the concave and convex surface of the basin insulator, and an optimization scheme for the design of the particle trap is proposed from three aspects: the electric field regulation of the trap, the captured probability of particles, and the trap location. The proposed research shows that, with respect to the motion characteristics of the particles, this paper selects circular hole-shaped trap and its thickness, slot spacing, and slot width are 10 mm, 6 mm, and 8 mm, respectively. When the traps are arranged, one at the bottom of the shell at 70 mm and 80 mm from each side of the concave and convex insulator, the capture probability of the traps on both sides can be as high as 78% and 70%, respectively. Therefore, the analysis and optimization method in this paper has important reference value according to similarity concepts for optimizing particle traps in AC GIL at a certain voltage level.

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He, Deyi, Chusheng Liu, and Sai Li. "The Nonlinear Dynamic Behavior of a Particle on a Vibrating Screen Based on the Elastoplastic Contact Model." Separations 9, no. 8 (August 12, 2022): 216. http://dx.doi.org/10.3390/separations9080216.

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The dynamic response of particles is closely related to screening efficiency. To study the dynamic response of particles, the dynamic equations of a particle on a screening surface are established based on the elastoplastic contact model of spherical particles and are solved for the coal particle. Then, the trajectories of the particles are given with different falling heights and particle radii. The completely different trajectories with slight changes in the falling height and particle radius indicate strong nonlinearity. Second, the nonlinear dynamic behavior under different amplitudes and frequencies is discussed, and the route of transition from quasiperiodic motion to chaotic motion is revealed. Finally, we discuss the average speed along the screening surface considering the frequency, amplitude, friction coefficient, inclination angle, and vibration direction angle. In addition, the convergence conditions of particle motion are proposed, and they are only affected by the inclination angle and friction angle. The results show that in the normal direction of the vibrating screen, the particle motion is quasiperiodic at low frequencies. With increasing frequency, the motion of the particle becomes chaotic, and its Poincaré map becomes petal-shaped. In addition, the number of petals increases at the mutation of the bifurcation diagram. The increase in frequency, amplitude and inclination angle and the decrease in friction coefficient lead to an increase in particle speed along the screen surface. In addition, the particle speed reaches a maximum when the vibration direction angle is 65°. This work provides a theoretical basis for controlling the thickness of granular material flow on a vibrating screen and selecting screening process parameters.

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Li, Xiaolin, Yunkai Li, Yichao Zhu, Yaojian Liang, Yunfei Xue, and Lu Wang. "Effect of W particle size on mechanical properties of a tungsten heavy alloy." Journal of Physics: Conference Series 2383, no. 1 (December 1, 2022): 012135. http://dx.doi.org/10.1088/1742-6596/2383/1/012135.

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Preparing fine tungsten particles tungsten heavy alloys (WHAs) is a method to improve the susceptibility to adiabatic shear of WHAs. In this paper, W-AlCrFeNiV alloy (W-HEA) with different size W particles were prepared by laser ultrashort-time liquid phase sintering (LULPS) and liquid phase sintering (LPS). The effects of W particle size of W-HEA on mechanical property and susceptibility to adiabatic shear are studied. The results show that W-HEA with 3 μm W particles has excellent mechanical properties-tensile strength nearly 1500 MPa. The tensile strength is 58% higher than that W-HEA with 20 μm W particle. W-HEA with 3 μm W particle dynamic compression strength is 2200 MPa under 4000 s-1. The dynamic strength is 22% higher than that tungsten heavy alloy with 20 μm W particle. And the smaller W particles are, the stronger susceptibility to adiabatic shear is. The adiabatic shear band width of W-HEA with 3 μm W particles is 10 μm after dynamic compression.

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Hu, Xiaolin, and Xiaofeng Jia. "A dynamic lattice method for elastic seismic modeling in anisotropic media." GEOPHYSICS 81, no. 3 (May 2016): T131—T143. http://dx.doi.org/10.1190/geo2015-0511.1.

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Basing on a particle network model, we have developed a dynamic lattice approach to simulate seismic wave propagation in transversely isotropic (TI) media with tilted symmetry axis (TTI). Different from other wave-equation-based numerical methods, the dynamic lattice approach calculates the micromechanical interactions between particles in the lattice instead of solving the wave equation. We implement Lagrange’s equations to transform these interactions into elastic forces acting upon each particle. By solving the equations of motion, we obtain the disturbances of particles. Therefore, seismic wave motions in continua are approximated by displacements of these particles. Elastic features of the continuum are represented by properties of the particle lattice, including the physical properties of particles and the micromechanical interactions between particles. In the case of TI media, it is a challenge to find the correct particle lattice model that can reflect the anisotropic nature of TI media. We have determined the theoretical connection between the TI medium and the particle lattice model, allowing us to model elastic seismic waves in heterogeneous TI media. Furthermore, we have linearized the propagator to improve the CPU efficiency of our method for seismic wave simulation. We have applied the method to reverse time migration on a TI model to test its usefulness in complex media imaging.

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Qian, Fu Ping, and Xian Kun Yu. "Numerical Simulation to Study the Effect of the Particle Deposition Morphology on the Filtration Efficiency of the Fibrous Media." Advanced Materials Research 518-523 (May 2012): 1767–70. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.1767.

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The grid “freezing” method in computational fluid dynamics (CFD) was used to deal with the moving boundary in this study, which can make the dynamic boundary into the fixed boundary and qualitatively describe the particle deposition morphology on the surface of the fibrous media. Meanwhile, the filtration efficiencies of the fibrous media with different deposition particle numbers and particle deposition morphologies were calculated using numerical simulation method. The results show that particle deposition on the surface of the fibrous media can help to improve the filtration performance, and in the steady-state, the effect is not obvious, but in the unsteady-stage, the particle deposition can improve the filtration efficiency greatly. In addition, the disposition morphology that has greater contact area with the oncoming particles is conductive to fibrous media capturing particles.

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Ha, Seung-Yeal, Jinwook Jung, Jeongho Kim, Jinyeong Park, and Xiongtao Zhang. "Emergent behaviors of the swarmalator model for position-phase aggregation." Mathematical Models and Methods in Applied Sciences 29, no. 12 (November 2019): 2225–69. http://dx.doi.org/10.1142/s0218202519500453.

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We study emergent dynamics of the swarmalator model [K. P. O’Keeffe, H. Hong and S. H. Strogatz, Oscillators that sync and swarm, Nature Commun. 8 (2017) 1504] describing the dynamic interplay of aggregation and synchronization dynamics for interacting many-particle systems. For the particle aggregation, we employ the nonlinear aggregation system with singular attractive–repulsive couplings depending on the phase differences, while we use the Kuramoto-type model with the singular coupling strength depending on the spatial distances for the dynamics of phases. We show how collective behaviors emerge from the dynamic interplay between position aggregation and phase synchronization. We introduce some sufficient framework leading to the positive minimal relative distances between particles and its uniform upper bound. We also show the convergence of position under some sufficient conditions.

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Rabinski, G., and D. Thomas. "Dynamic digital image analysis: emerging technology for particle characterization." Water Science and Technology 50, no. 12 (December 1, 2004): 19–26. http://dx.doi.org/10.2166/wst.2004.0691.

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The feasibility of applying dynamic imaging analysis technology to particle characterization has been evaluated for application in the water sector. A system has been developed which captures in-situ images of suspended particles in a flowing sample stream and analyzes these images in real time to determine particle size and concentration. The technology can measure samples having a wide range of particle sizes (∼1.5 to 1,000 μm equivalent circular diameter) and concentrations (<1 to >1 million/ml). The system also provides magnified images of particles for visual analysis of properties such as size, shape and grayscale level. There are no sample preparation requirements and statistically accurate results are produced in less than three minutes per sample. The overall system architecture is described. The major design challenges in developing a practical system include obtaining adequate contrast for the range of particle materials found in typical water samples and achieving this under operating conditions permitting an adequate sample processing rate for real time feedback of results. Performance of the instrument is reported in reference to industry accepted particle standards and applications as an analytical tool for the water industries are considered.

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Wang, Xiaodong, Kai Chen, Ting Kang, and Jie Ouyang. "A Dynamic Coarse Grain Discrete Element Method for Gas-Solid Fluidized Beds by Considering Particle-Group Crushing and Polymerization." Applied Sciences 10, no. 6 (March 12, 2020): 1943. http://dx.doi.org/10.3390/app10061943.

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The discrete element method (DEM) coupled with computational fluid dynamics (CFD) is used extensively for the numerical simulation of gas-solid fluidized beds. In order to improve the efficiency of this approach, a coarse grain model of the DEM was proposed in the literature. In this model, a group of original particles are treated as a large-sized particle based on the initial particle distribution, and during the whole simulation process the number and components of these particle-groups remain unchanged. However, collisions between particles can lead to frequent crushing and polymerization of particle-groups. This fact has typically been ignored, so the purpose of this paper is to rationalize the coarse grain DEM-CFD model by considering the dynamic particle-group crushing and polymerization. In particular, the effective size of each particle-group is measured by a quantity called equivalent particle-group diameter, whose definition references the equivalent cluster diameter used by the energy-minimization multi-scale (EMMS) model. Then a particle-group crushing criterion is presented based on the mismatch between the equivalent diameter and actual diameter of a particle-group. As to the polymerization of two colliding particle-groups, their velocity difference after collision is chosen as a criterion. Moreover, considering the flow heterogeneity induced by the particle cluster formation, the EMMS drag force model is adopted in this work. Simulations are carried out by using a finite volume method (FVM) with non-staggered grids. For decoupling the Navier-Stokes equations, the semi-implicit method for pressure linked equations revised (SIMPLER) algorithm is used. The simulation results show that the proposed dynamic coarse grain DEM-CFD method has better performance than the original one.

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Kurzhals, Anja, Christoph Brandt-Wunderlich, Niels Grabow, Wolfram Schmidt, and Klaus-Peter Schmitz. "Dynamic image analysis of transparent particles released during the simulated use test of cardiovascular devices." Current Directions in Biomedical Engineering 5, no. 1 (September 1, 2019): 203–6. http://dx.doi.org/10.1515/cdbme-2019-0052.

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AbstractFor product approval of coated cardiovascular devices, the assessment of particle release is essential. Particularly challenging are delivery systems equipped with hydrophilic coatings releasing highly transparent particles. The aim of this study was to compare two different methods of particle counting, namely the light obscuration method and the dynamic image analysis (DIA), with respect to optical transparent particles. The particles were collected during the simulated use of cardiovascular catheters and analysed in suspension with a dynamic imaging device (FlowCam, Fluid Imaging Technologies). Particles were detected by a greyscale threshold and imaged to analyse their shape and transparency. The statistical influence of the threshold on particle counts and size distribution was determined and compared to light obscuration particle counting (Model 9703 with sensor HRLD 400CE, HIAC ROYCO). The light obscuration method provided lower particle counts in suspensions containing a high amount of transparent particles. The lower the detection threshold, the higher the particle counts were. In conclusion, it is important to adapt the threshold value for samples that are expected to contain a high amount of transparent particles. DIA may be suggested as a valuable additional method for particulate analysis.

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Sippola, Petteri, Jari Kolehmainen, Ali Ozel, Xiaoyu Liu, Pentti Saarenrinne, and Sankaran Sundaresan. "Experimental and numerical study of wall layer development in a tribocharged fluidized bed." Journal of Fluid Mechanics 849 (June 26, 2018): 860–84. http://dx.doi.org/10.1017/jfm.2018.412.

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The effects of triboelectricity in a small-scale fluidized bed of polyethylene particles were investigated by imaging the particle layer in the vicinity of the column wall and by measuring the pressure drop across the bed. The average charge on the particles was altered by changing the relative humidity of the gas. A triboelectric charging model coupled with a computational fluid dynamics–discrete element method (CFD-DEM) model was utilized to simulate gas–particle flow in the bed. The electrostatic forces were evaluated based on a particle–particle particle–mesh method, accounting for the surface charge on the insulating walls. It was found that simulations with fixed and uniform charge distribution among the particles capture remarkably well both the agglomeration of the particles on the wall and the associated decrease in the pressure drop across the bed. With a dynamic tribocharging model, the charging rate had to be accelerated to render the computations affordable. Such simulations with an artificial acceleration significantly over-predict charge segregation and the wall becomes rapidly sheeted with a single layer of strongly charged particles.

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BUTLER, JASON E., and ERIC S. G. SHAQFEH. "Dynamic simulations of the inhomogeneous sedimentation of rigid fibres." Journal of Fluid Mechanics 468 (October 8, 2002): 205–37. http://dx.doi.org/10.1017/s0022112002001544.

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We have simulated the dynamics of suspensions of fibres sedimenting in the limit of zero Reynolds number. In these simulations, the dominant inter-particle force arises from hydrodynamic interactions between the rigid, non-Brownian fibres. The simulation algorithm uses slender-body theory to model the linear and rotational velocities of each fibre. To include far-field interactions between the fibres, the line distribution of force on each fibre is approximated by making a Legendre polynomial expansion of the disturbance velocity on the fibre, where only the first two terms of the expansion are retained in the calculation. Thus, the resulting linear force distribution can be specified completely by a centre-of-mass force, a couple, and a stresslet. Short-range interactions between particles are included using a lubrication approximation, and an infinite suspension is simulated by using periodic boundary conditions. Our numerical results confirm that the sedimentation of these non-spherical, orientable particles differs qualitatively from the sedimentation of spherical particles. The simulations demonstrate that an initially homogeneous, settling suspension develops clusters, or streamers, which are particle rich surrounded by clarified fluid. The instability which causes the heterogeneous structure arises solely from hydrodynamic interactions which couple the particle orientation and the sedimentation rate in particle clusters. Depending upon the concentration and aspect ratio, the formation of clusters of particles can enhance the sedimentation rate of the suspension to a value in excess of the maximum settling speed of an isolated particle. The suspension of fibres tends to orient with gravity during the sedimentation process. The average velocities and orientations, as well as their distributions, compare favourably with previous experimental measurements.

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GU, G. Q., K. W. YU, and P. M. HUI. "RELAXATION THEORY FOR DYNAMIC ELECTRORHEOLOGICAL EFFECT." International Journal of Modern Physics B 16, no. 17n18 (July 20, 2002): 2597–602. http://dx.doi.org/10.1142/s0217979202012712.

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We present a model to investigate the induced interaction between rotating particles in ER fluids. For particle undergoes uniform rotation or harmonic oscillation, the effects due to dipole relaxation are studied analytically. The induced interaction between particles which are rotating uniformly is derived. The result shows that the dynamic effect reduces the interaction between particles. A proof on the consistency of the relaxation equation with charge conservation upon rotation is also given.

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Alizadehrad, Davod, and Dmitry A. Fedosov. "Static and dynamic properties of smoothed dissipative particle dynamics." Journal of Computational Physics 356 (March 2018): 303–18. http://dx.doi.org/10.1016/j.jcp.2017.12.009.

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Frey, H., A. Beck, X. Huang, J. A. van Bokhoven, and M. G. Willinger. "Dynamic interplay between metal nanoparticles and oxide support under redox conditions." Science 376, no. 6596 (May 27, 2022): 982–87. http://dx.doi.org/10.1126/science.abm3371.

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The dynamic interactions between noble metal particles and reducible metal-oxide supports can depend on redox reactions with ambient gases. Transmission electron microscopy revealed that the strong metal-support interaction (SMSI)–induced encapsulation of platinum particles on titania observed under reducing conditions is lost once the system is exposed to a redox-reactive environment containing oxygen and hydrogen at a total pressure of ~1 bar. Destabilization of the metal–oxide interface and redox-mediated reconstructions of titania lead to particle dynamics and directed particle migration that depend on nanoparticle orientation. A static encapsulated SMSI state was reestablished when switching back to purely oxidizing conditions. This work highlights the difference between reactive and nonreactive states and demonstrates that manifestations of the metal-support interaction strongly depend on the chemical environment.

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Durand, Stan, Brian E. Jackson, William C. Fonteno, and Jean-Charles Michel. "Quantitative Description and Classification of Growing Media Particle Morphology through Dynamic Image Analysis." Agriculture 13, no. 2 (February 8, 2023): 396. http://dx.doi.org/10.3390/agriculture13020396.

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The physical properties of growing media are dependent on the morphological characteristics of the particles composing them. Thus, their characteristics can be more precisely altered for specific purposes by a better morphological design of materials to optimize the use of raw materials and increase water efficiency. There are many references on the relationship between basic particle size and physical properties, but the arrangement of the particles and the resulting physical properties are also affected by the shape of the particles. Growing media have seldom been characterized by shape criteria and, therefore, their influence remains unknown. A dynamic image analyzer, the QicPic device, was used to assess particle shape and size for a wide diversity of growing media constituents. As well as FeretMAX and ChordMIN diameters describing individual particle length and width, respectively, individual particle shape was analyzed in terms of several descriptors (aspect ratio, circularity, roundness, and convexity). A classification was established to discern different particle shapes and all materials were described accordingly. Correlations between particle morphology descriptors were reported, showing that the greater the particle length, the smaller the width/length ratio, circularity, roundness, and convexity. Circularity, roundness, particle length, and its associated relative span were identified as the most relevant parameters describing materials’ morphology. This work shows a large diversity in particle morphology of growing media constituents, which were categorized into four classes of materials. Three classes were mainly described according to their particle shapes, with a decreasing elongation and an increasing circularity, roundness, and convexity: (1) fine and coarse wood and coir fibers; (2) all Sphagnum white peats, milled or sod; and (3) black peats, sedge peat, coir pith, fresh and composted pine bark, green waste compost, and perlite. A fourth class was represented by coir medium (mixing pith and fibers) and was above all characterized by high diversity in particle length. These findings extend the characterization of the materials for a more thorough evaluation of the links between particle morphology and physical properties.

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Yao, Hai Tao, Hai Qiang Chen, and Tuan Fa Qin. "Niche PSO Particle Filter with Particles Fusion for Target Tracking." Applied Mechanics and Materials 239-240 (December 2012): 1368–72. http://dx.doi.org/10.4028/www.scientific.net/amm.239-240.1368.

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An improved particle filter algorithm is proposed to track a randomly moving target in video. In particle filter framework, a particle swarm optimization improved by niche technique which implemented by restricted competition selection is integrated. It can move particles into high likelihood area of target and form multi-population distribution, so that the searching capability of particles is enhanced and then the adaptation to the change of dynamic target state is improved. The particles of niching particle swarm optimization and the particles of particle filter are integrated for new particle weight calculation and finally realize a new particle filter for target tracking in video sequence.

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Wang, Jianping, Haotian Zhang, Tao Chen, and Linjian Ma. "Simulation Study of Breakage in Coral Sand Particles under Dynamic Confined Compression." Shock and Vibration 2023 (March 8, 2023): 1–10. http://dx.doi.org/10.1155/2023/3382996.

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This paper reports a simulation-based dynamic confined compression analysis of coral sand under an impact load using the discrete element method (DEM). The evolution of particle breakage on the mesoscale was studied by investigating force chain distributions, crack development, and breakage modes. Crushable sand particles were simulated by replacing rigid particles with flexible basic unit aggregates. The Weibull parameters were incorporated within the mesoscopic parameters of particles, and random numbers were introduced. The obtained results for particle strengths were consistent with the experimental data. The numerical results demonstrated that the force chain was significantly strengthened along the loading axis during loading and weakened during unloading. The cracks were primarily generated along the strong force chain, and particle breakage caused the strong force chain to move towards relatively more complete fragments nearby. The crack was primarily oriented along the loading axis, and its anisotropy was observed to decrease with an increase in the load. Before yielding, particle breakage in the specimen was dominated by attrition at the edges and corners. After yielding, the crack extended into the particle perpendicular to the intergranular contact surface and was deflected by the simultaneous influence of pores. The fracture and shattering of particles occurred successively, and the consequent fall-off and slip filling of the fragments promoted the deformation development.

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Protière, Suzie. "Particle Rafts and Armored Droplets." Annual Review of Fluid Mechanics 55, no. 1 (January 19, 2023): 459–80. http://dx.doi.org/10.1146/annurev-fluid-030322-015150.

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Particles floating at interfaces are commonly observed in nature, as well as in industrial processes. When the particles are non-Brownian particles, large deformations of the interface are created that induce long-ranged capillary interactions and lead to the formation of particle rafts with unique characteristics. In this review we discuss recent efforts in investigating particle raft formation and the role of the rafts’ own weight during dynamic clustering. Under specific conditions, these rafts can ultimately collapse and sink. When subjected to external or internal forces, the raft undergoes large deformations that test the mechanical characteristics of this interfacial composite material. It can behave as a continuous elastic sheet under compression, although its discrete nature can also trigger its fragmentation via interparticle interactions. Finally, armored droplets, drops covered by a protective shell of particles, can lose their integrity when submitted to dynamic deformations, resulting in the ejection of particles or the fracturing of the armor. Open questions to understand the properties of this material are highlighted and future research to understand the fundamental physics of particle rafts, the customization of the cluster formation, or the disassembly of this collective material is suggested.

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Dratler, D. I., and W. R. Schowalter. "Dynamic simulation of suspensions of non-Brownian hard spheres." Journal of Fluid Mechanics 325 (October 25, 1996): 53–77. http://dx.doi.org/10.1017/s0022112096008038.

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In this work, we investigate the suitability of models based solely on continuum hydrodynamics for Stokesian Dynamics simulations of sheared suspensions of non-Brownian hard spheres. The suspensions of interest consist of monolayers of uniform rigid spheres subjected to a linear shear field. Areal fractions ranged from ϕa = 0.2 to 0.6. For these suspensions, two sets of Stokesian Dynamics simulations were performed. For the first set, particle interactions were assumed to be strictly hydrodynamic in nature. These simulations are analogous to those of Brady & Bossis (1985) and Chang & Powell (1993). For the second set of simulations, particles were subjected to both hydrodynamic and short-range repulsive forces. The repulsion serves as a qualitative model of non-hydrodynamic effects important when particle separation distances are small. Results from both sets of simulations were found to be within the range of established experimental data for viscosities of suspensions. However, simulations employing the pure hydrodynamic model lead to very small separation distances between particles. These small separations give rise to particle overlaps that could not be eliminated by time-step refinement. The instantaneous number of overlaps increased with density and typically exceeded the number of particles at the highest densities considered. More critically, for very dense suspensions the simulations failed to approach a long-time asymptotic state. For simulations employing a short-range repulsive force, these problems were eliminated. The repulsion had the effect of preventing extremely small separations, thereby eliminating particle overlaps. At high concentrations, viscosities computed using the two methods are significantly different. This suggests that the dynamics of particles near contact have a significant impact on bulk properties. Furthermore, the results suggest that a critical aspect of the physics important at small particle separation distances is missing from the pure hydrodynamic model, making it unusable for computing microstructures of dense suspensions. In contrast, simulations employing a short-range repulsive force appear to produce more realistic microstructures, and can be performed even at very high densities.

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YANG, Shiqin, and Yuji SATO. "Dynamic Heterogeneous Particle Swarm Optimization." IEICE Transactions on Information and Systems E100.D, no. 2 (2017): 247–55. http://dx.doi.org/10.1587/transinf.2016edp7219.

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REN, Xiao-bo, and Zhong-xiu YANG. "Dynamic diffusion particle swarm optimization." Journal of Computer Applications 30, no. 1 (March 11, 2010): 159–61. http://dx.doi.org/10.3724/sp.j.1087.2010.00159.

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Ahn, Jeongho, and Jared Wolf. "Dynamic impact of a particle." Involve, a Journal of Mathematics 6, no. 2 (September 1, 2013): 147–67. http://dx.doi.org/10.2140/involve.2013.6.147.

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Zhao, Ling, and Guang Yu She. "Experimental Investigation on Dynamic Characteristics of NOPD Thin-Wall Frame Structure." Applied Mechanics and Materials 71-78 (July 2011): 138–43. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.138.

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The free vibration experiments for the NOPD frame structure were performed to investigate the dynamic characteristics of the frame. The influences of factors such as particle filling ratio, particle filling scheme and vibration direction of the frame on the damping effect are discussed by means of test data. Test results indicate that the particle filling ratio is a principal influencing factor for the damping effect of the frame. Under the same particle filling scheme and filling ratio, the damping increments for out plane vibration of the frame with smaller structural rigidity are normally larger than those for in plane vibration with larger structural rigidity. Within the three schemes of particle filling, the most prominent damping improvement exists in the particle-in-beam scheme under the same filling ratio and the corresponding maximum damping increment reaches 218% for out plane vibration. To obtain the most significant particle damping effect, the most effective scheme of particle filling is to put particles into the cavities of components with large vibration displacement.

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Dong, Shu Xia, and Liang Tang. "Dynamic Neighborhood Particle Swarm Optimization Based on External Archive." Applied Mechanics and Materials 333-335 (July 2013): 1374–78. http://dx.doi.org/10.4028/www.scientific.net/amm.333-335.1374.

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According to the defect of falling into a local optimum when dealing with multimodal problems with basic particle swarm optimization, a dynamic neighborhood particle swarm optimization with external archive (EA-DPSO) is proposed. The Ring topology, All topology and Von Neumann topology are adopted, and dynamically refining particle history optimal position, and then store them on the external archive. In terms of particles characteristics in the external archive, a kind of effective extract mechanism method is designed to choose learning sample. Three peak problems as simulation function are chosen and the results show that EA-DPSO can effectively jump out of local optimal solution. Therefore, it can be seen as an effective algorithm for solving multimodal problems.

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Journal articles on the topic 'Particle dynamic'

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