Article
Computer Science, Interdisciplinary Applications
G. C. Yang, S. C. Yang, L. Jing, C. Y. Kwok, Y. D. Sobral
Summary: This paper presents a lattice Boltzmann framework for accurate and efficient simulation of free-surface granular flows. The lattice Boltzmann implementation is validated and applied to simulate steady-state and transient granular flow problems. The proposed lattice Boltzmann formulation is highly efficient and has the potential to conduct three-dimensional continuum simulation of large-scale geophysical flows with microscopic granular physics.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Engineering, Chemical
Xitong Zhang, Jinggang Zhang, Haihu Liu
Summary: In this study, a lattice Boltzmann method is employed to simulate a particle-laden droplet under a simple shear flow. The effects of particle concentration, viscosity ratio of droplet to ambient fluid, and particle inertia on droplet deformation and particle movement are investigated. It is found that the addition of particles reduces the interfacial free energy and leads to increased droplet deformation. Additionally, the viscosity ratio and particle inertia both influence the droplet deformation, with the former showing a monotonic decrease and the latter having a significant effect only at high Reynolds numbers.
Article
Physics, Fluids & Plasmas
Dario Maggiolo, Francesco Picano, Federico Toschi
Summary: Through pore-scale numerical simulations, it has been shown that directional-dependent two-phase flow behavior can be achieved in anisotropic porous media with controlled design. The results demonstrate distinct invasion dynamics based on the direction of fluid injection relative to the medium orientation.
Article
Mechanics
Da Hui, Zhijing Xu, Wenbin Wu, Guiyong Zhang, Qian Wu, Moubin Liu
Summary: This paper investigates the dynamics of a pair of particles settling in non-Newtonian fluids. It finds that the horizontal migration direction in shear-thinning fluid is different from that in Newtonian fluid, and yield stress plays a dominant role in sedimentation velocity and separation distance. Three sedimentation structures are identified during the sedimentation process.
Article
Engineering, Electrical & Electronic
Cael Warner, Loic Markley, Kenneth J. Chau
Summary: This article compares the performance of the Yee-lattice finite-difference time-domain method and the Hauser and Verhey electrodynamic lattice-Boltzmann method in solving electromagnetic scattering problems. The results show that the HV ELBM evaluates the time-averaged force density in a shorter computational time with less error.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Mathematics, Applied
Radek Fucik, Robert Straka
Summary: The presented method is applicable to a general matrix lattice Boltzmann method for deriving equivalent finite difference equations and subsequent equivalent partial differential equations, which can be used for advection diffusion equations and Navier-Stokes equations. The algorithm for obtaining coefficients and deriving equations is implemented for different velocity models, ensuring finiteness and convergence after a certain number of iterations. The implementation is done in C++ with the GiNaC library and is available under the GNU general public license (GPL).
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2021)
Article
Engineering, Chemical
Li Zhao, Qiang Zhou, Bolun Yang, Xiao Chen
Summary: Lattice Boltzmann simulations were used to investigate the drag force on fixed monodisperse spheres at low Reynolds numbers. The results showed that the solid volume fraction in the surrounding part had a significant impact on the drag force of the center particles, and this effect became more prominent as the solid volume fraction or the inhomogeneities of the central particles increased. A new drag model considering the surrounding influence was proposed, which showed promise in studying gas-solid interactions in flows with complex structures.
Article
Chemistry, Analytical
Lizhong Huang, Jiayou Du, Zefei Zhu
Summary: This study numerically investigates the migration of neutrally buoyant circular particles driven by pulsatile velocity in a 2D Poiseuille flow channel using the immersed boundary-lattice Boltzmann method (IB-LBM). The research examines the impact of Reynolds number (25 <= Re <= 200) and blockage ratio (0.15 <= k <= 0.40) on particle migration under pulsatile and non-pulsatile velocity, showing that the particle exhibits underdamped oscillation and migrates back to the channel centerline during zero-velocity periods in pulsatile cases. Additionally, the lateral travel distance increases with Reynolds number, while the blockage ratio has minimal effect.
Article
Mechanics
Liuming Yang, Chang Shu, Zhen Chen, Guoxiang Hou, Yan Wang
Summary: The improved multiphase lattice Boltzmann flux solver (IMLBFS) is proposed based on the Chapman-Enskog analysis of the MLBM to overcome limitations in the original MLBFS. By considering the surface tension force when reconstructing numerical interface fluxes, the IMLBFS is found to be more stable and efficient compared to the MLBFS.Simulations on various flow conditions demonstrate that the IMLBFS predicts smaller spurious velocities and outperforms the original MLBFS.
Article
Environmental Sciences
Bijan Moradi, Iman Zojaji
Summary: This study investigates the mechanisms of co-current fluid flow in a heterogeneous porous media using the lattice Boltzmann method and a hybrid phase-field model. The results show that increasing the injection velocity reduces the displacement efficiency and increases velocity field fluctuations. Additionally, changing the wetting conditions and interfacial tension also affect the sweep efficiency.
WATER RESOURCES RESEARCH
(2022)
Article
Engineering, Geological
K. Sawayama, T. Ishibashi, F. Jiang, T. Tsuji, Y. Fujimitsu
Summary: This study investigates simultaneous changes in hydraulic and geophysical properties of natural rock fractures under increasing normal stress, and correlates the property changes through coupling experiments and digital fracture simulations. It is found that electrical resistivity is linked with permeability and flow area, while elastic wave velocity is roughness-dependent.
ROCK MECHANICS AND ROCK ENGINEERING
(2021)
Article
Computer Science, Software Engineering
Wei Li, Mathieu Desbrun
Summary: This paper presents an improved numerical simulation method that can accurately simulate complex fluid phenomena and effectively handle fluid-solid coupling. It introduces a series of numerical improvements in momentum exchange, interfacial forces, and two-way coupling to reduce simulation artifacts and expand the types of fluid-solid coupling that can be efficiently simulated. The benefits of the solver are demonstrated through challenging simulation results and comparisons to previous work and real footage.
ACM TRANSACTIONS ON GRAPHICS
(2023)
Article
Computer Science, Software Engineering
Wei Li, Yihui Ma, Xiaopei Liu, Mathieu Desbrun
Summary: This paper proposes a new solver for coupling the incompressible Navier-Stokes equations with a conservative phase-field equation to simulate multiphase flows. The resulting solver shows efficiency, versatility, and reliability in dealing with large density ratios, high Reynolds numbers, and complex solid boundaries.
ACM TRANSACTIONS ON GRAPHICS
(2022)
Article
Mechanics
Shang-Gui Cai, Sajad Mozaffari, Jerome Jacob, Pierre Sagaut
Summary: This paper applies an immersed boundary-turbulence wall modeling approach to investigate turbulent flows over a generic car geometry, known as the Ahmed body. The study shows that the near-wall solution is significantly deteriorated compared to the body-fitted simulation, but enhanced wall treatments proposed in the literature can effectively address this issue.
Article
Mechanics
Yi Zhou, Zhengdao Wang, Yuehong Qian, Hui Yang, Yikun Wei
Summary: This study presents a numerical investigation on flow around two square cylinders in different arrangements, revealing various flow patterns that can be categorized into three types depending on the spacing between the cylinders. The dependence of flow parameters on spacing is demonstrated, and the relationship between flow pattern and lift and drag coefficients is explored.
Article
Chemistry, Physical
Masaya Kozakai, Kenji Date, Yutaka Tabe, Takemi Chikahisa
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2016)
Article
Chemistry, Physical
Satoshi Sakaida, Yutaka Tabe, Takemi Chikahisa
JOURNAL OF POWER SOURCES
(2017)
Article
Electrochemistry
Yusuke Aoyama, Yutaka Tabe, Ryo Nozaki, Kengo Suzuki, Takemi Chikahisa, Toshihiro Tanuma
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2018)
Article
Thermodynamics
Yutaka Tabe, Satoshi Sakaida, Takemi Chikahisa
JOURNAL OF THERMAL SCIENCE AND TECHNOLOGY
(2018)
Article
Chemistry, Physical
Satoshi Sakaida, Yutaka Tabe, Kotaro Tanaka, Mitsuru Konno
Summary: This study investigated water transport in a novel gas diffusion layer (GDL) with hydrophilic-hydrophobic patterns. It was found that water motion in hydrophilic GDL could be reproduced by a scale model, and computational load could be reduced by using Capillary numbers (Ca) similar to 10(-3). Simulation with Ca similar to 10(-3) showed that a GDL with a straight region of contact angle 50 degrees minimized water accumulation.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Electrochemistry
Yutaka Tabe, Naoyuki Wakatake, Yuta Ishima, Takemi Chikahisa
Summary: In startups of polymer electrolyte fuel cells at temperatures close to 0 degrees C below freezing, water produced by the cathode reaction is present in a supercooled state and may freeze, impacting the startup process.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2021)
Article
Engineering, Mechanical
Biness Lukwesa, Naoya Takahashi, Kengo Suzuki, Yutaka Tabe, Takemi Chikahisa
Summary: This paper examines measures to integrate high shares of variable renewable energy (VRE) in power supply systems. Geographical distribution of VRE locations can reduce surplus power generation, while increasing transmission capacity and introducing energy storage facilities can effectively minimize the amount of surplus power generated.
MECHANICAL ENGINEERING JOURNAL
(2022)
Article
Electrochemistry
Yutaka Iizuka, Yutaka Tabe, Yuki Kitami, Suguru Uemura
Summary: In order to increase the power output of polymer electrolyte fuel cells, this study evaluates the effects of condensed water on the oxygen transport resistance. The resistance increase is separated into pressure-dependent and -independent components. The results show that both components increase with temperature. Observations suggest that the accumulation of condensed water at the interface between the micro-porous layer and catalyst layer can disrupt oxygen transport.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2022)
Article
Engineering, Mechanical
Biness Lukwesa, Suguru Uemura, Yutaka Tabe
Summary: This study aims to determine the optimal utilization conditions for geographically distributed renewable energy electricity by the power transmission and distribution (PTD) company through an optimization model that minimizes the company's cost. The results show that the VRE utilization depends on the electricity prices and the price difference between thermal and VRE electricity prices is a key factor.
MECHANICAL ENGINEERING JOURNAL
(2023)
Article
Electrochemistry
Satoshi Sakaida, Yutaka Tabe, Takemi Chikahisa, Kotaro Tanaka, Mitsuru Konno
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2019)
Proceedings Paper
Electrochemistry
Y. Tabe, T. Satake, T. Iiri, T. Hayashi, T. Chikahisa
POLYMER ELECTROLYTE FUEL CELLS 17 (PEFC 17)
(2017)
Proceedings Paper
Electrochemistry
R. Nozaki, Y. Tabe, T. Chikahisa, T. Tanuma
POLYMER ELECTROLYTE FUEL CELLS 17 (PEFC 17)
(2017)
Proceedings Paper
Electrochemistry
S. Sakaida, Y. Tabe, T. Chikahisa
POLYMER ELECTROLYTE FUEL CELLS 17 (PEFC 17)
(2017)
Proceedings Paper
Green & Sustainable Science & Technology
Kengo Suzuki, Naoya Takahashi, Yutaka Tabe, Takemi Chikahisa
2017 INTERNATIONAL CONFERENCE ON GREEN ENERGY AND APPLICATIONS (ICGEA 2017)
(2017)
Article
Mathematics, Applied
Junfeng Cao, Ke Chen, Huan Han
Summary: This paper proposes a two-stage image segmentation model based on structure tensor and fractional-order regularization. In the first stage, fractional-order regularization is used to approximate the Hausdorff measure of the MS model. The solution is found using the ADI scheme. In the second stage, thresholding is used for target segmentation. The proposed model demonstrates superior performance compared to state-of-the-art methods.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2024)
Article
Mathematics, Applied
Dylan J. Oliver, Ian W. Turner, Elliot J. Carr
Summary: This paper discusses a projection-based framework for numerical computation of advection-diffusion-reaction (ADR) equations in heterogeneous media with multiple layers or complex geometric structures. By obtaining approximate solutions on a coarse grid and reconstructing solutions on a fine grid, the computational cost is significantly reduced while accurately approximating complex solutions.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2024)
Article
Mathematics, Applied
Nathan V. Roberts, Sean T. Miller, Stephen D. Bond, Eric C. Cyr
Summary: In this study, the time-marching discontinuous Petrov-Galerkin (DPG) method is applied to the Vlasov equation for the first time, using backward Euler for a Vlasov-Poisson discretization. Adaptive mesh refinement is demonstrated on two problems: the two-stream instability problem and a cold diode problem.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2024)
Article
Mathematics, Applied
Yizhi Sun, Zhilin Sun
Summary: This work investigates the convexity of a specific class of positive definite probability measures and demonstrates the preservation of convexity under multiplication and intertwining product. The study reveals that any integrable function on an interval with a polynomial expansion of fast absolute convergence can be decomposed into a pair of positive convex interval probabilities, simplifying the study of interval distributions and discontinuous probabilistic Galerkin schemes.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2024)
Article
Mathematics, Applied
Bhagwan Singh, Komal Jangid, Santwana Mukhopadhyay
Summary: This paper examines the prediction of bending characteristics of nanoscale materials using the Moore-Gibson-Thompson thermoelasticity theory in conjunction with the nonlocal strain gradient theory. The study finds that the stiffness of the materials can be affected by nonlocal and length-scale parameters, and the aspect ratios of the beam structure play a significant role in bending simulations.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2024)
Article
Mathematics, Applied
Guoliang Wang, Bo Zheng, Yueqiang Shang
Summary: This paper presents and analyzes a parallel finite element post-processing algorithm for the simulation of Stokes equations with a nonlinear damping term, which integrates the algorithmic advantages of the two-level approach, the partition of unity method, and the post-processing technique. The algorithm generates a global continuous approximate solution using the partition of unity method and improves the smoothness of the solution by adding an extra coarse grid correction step. It has good parallel performance and is validated through theoretical error estimates and numerical test examples.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2024)
Article
Mathematics, Applied
Hao Xu, Zeng-Qi Wang
Summary: Fluid flow control problems are crucial in industrial applications, and solving the optimal control of Navier-Stokes equations is challenging. By using Oseen's approximation and matrix splitting preconditioners, we can efficiently solve the linear systems and improve convergence.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2024)
Article
Mathematics, Applied
Zhengya Yang, Xuejuan Chen, Yanping Chen, Jing Wang
Summary: This paper focuses on the high-order stable numerical solutions of the time-space fractional diffusion equation. The Fourier spectral method is used for spatial discretization and the Spectral Deferred Correction (SDC) method is used for numerical solutions in time. As a result, a high-precision numerical discretization scheme for solving the fractional diffusion equation is obtained, and the convergence and stability of the scheme are proved. Several numerical examples are presented to demonstrate the effectiveness and feasibility of the proposed numerical scheme.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2024)