Article
Mechanics
Jianghong Zhang, Gang Sun, Junjie Hu, Jian Wu, Maosen Xu
Summary: The presence of internal obstacles in square cavities significantly affects the flow and motion of solid particles. The motion of neutrally buoyant circular particles in a cavity with a circular obstacle was studied, considering factors such as obstacle size, location, initial particle position, and Reynolds number. The results show that the presence of obstacles alters the flow patterns, and the motion of particles is influenced by the Reynolds number.
Article
Mechanics
Chenlin Zhu, Lijuan Qian, Zhaowu Lin, Zhaosheng Yu
Summary: This study investigates the turbulent channel flow of a binary mixture of finite-size neutrally buoyant ellipsoidal particles using a parallel direct-forcing fictitious domain method. The results reveal that the variation of particle volume concentration has an impact on the flow properties under different friction Reynolds numbers and particle aspect ratios.
Article
Mechanics
Parisa Mirbod, Seyedmehdi Abtahi, Abbas Moradi Bilondi, Marco Edoardo Rosti, Luca Brandt
Summary: This study investigates turbulent suspension flows of non-Brownian, non-colloidal, neutrally buoyant and rigid spherical particles in a Newtonian fluid over porous media. The results show that the presence of particles in the free-flow region affects the mean velocity and concentration profiles due to variations in slip velocity and wall-normal fluctuations at the suspension-porous interface. The stress condition at the interface significantly influences the particle near-wall dynamics and migration towards the channel core, leading to large modulations of the overall flow drag.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Ali Yousefi, Pedro Costa, Francesco Picano, Luca Brandt
Summary: We investigated the dynamics of finite-size neutrally buoyant rigid spherical particles in channel flow and analyzed the connection between momentum transfer mechanisms and the bulk flow properties in the highly inertial regime. Our simulation results showed that the particle interactions are highly inhomogeneous and depend on the distance from the wall. In dense conditions and moderate Reynolds numbers, the particle-induced stresses dominate the dynamics, while turbulent stresses become more prominent at higher Reynolds numbers. This shift is associated with a reduced particle migration toward the channel core, which decreases the importance of particle-induced stress and increases turbulent activity.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Engineering, Mechanical
Francesco Romano
Summary: The correction of buoyancy effects for particles near a singular corner in microfluidic conditions is studied. The dynamics of a neutrally-buoyant particle all over the target domain is reconstructed using density-mismatched particle trajectories. The robustness of the proposed approach is demonstrated by deliberately ill-conditioning the reconstruction operator, showing good performance even with qualitatively-different density-mismatched orbit topologies or bundles of close trajectories.
ACTA MECHANICA SINICA
(2022)
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
Yansong Li, Chunxiao Xu, Lihao Zhao
Summary: In this paper, the authors investigate the dynamics of a neutrally buoyant prolate spheroid immersed in viscoelastic shear flows. The results show that the period of particle rotation changes with the solvent viscosity ratio and the mobility factor. They also identify five rotation modes of the spheroid under the effects of fluid inertia and fluid rheology. The findings highlight the importance of fluid inertia and fluid elasticity on the particle dynamics and suggest potential applications in controlling particle orientations in viscoelastic fluid flows.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Computer Science, Interdisciplinary Applications
Martin Reder, Daniel Schneider, Fei Wang, Simon Daubner, Britta Nestler
Summary: The distributed Lagrange multiplier/fictitious domain method in a phase-field formulation allows for simulation of rigid bodies in incompressible fluid flow, with the capability to handle complex boundary geometries and changes in shape during simulations. Multiple numerical experiments demonstrate its effectiveness in simulating problems involving differently shaped rigid bodies and particulate flows within complex boundary geometries like foam structures.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS
(2021)
Article
Mechanics
Xinchen Zhang, Francesco Zonta, Zhao F. Tian, Graham J. Nathan, Rey C. Chin, Alfredo Soldati
Summary: This paper investigates the dynamics of semi-and neutrally-buoyant particles in three-dimensional, stably-stratified turbulent channel flow. Particles released in different regions exhibit different behaviors, leading to distinct evolution of the particle swarms.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2021)
Article
Mechanics
Wenwei Liu, Chuan-Yu Wu
Summary: A numerical investigation using a lattice Boltzmann method coupled with a discrete element method was conducted on the lateral migration of a neutrally buoyant particle in Couette flow with two different thermal boundary conditions. The study explored the effects of the channel Reynolds number, the Grashof number, and the particle size on the migration behavior, revealing transitions in equilibrium positions under different thermal conditions. Additionally, new dimensionless parameters such as the Richardson number and the confinement ratio were found to govern the equilibrium positions of the particles.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2021)
Article
Energy & Fuels
Brian D. Yamashiro, Ingrid Tomac
Summary: The influence of rough rock surface geometry on flow behavior of neutrally buoyant particles in fractures is investigated in this study. The roughness level is evaluated by varying the root-mean-square asperity height and fractal dimension of synthetic surfaces. The effects of flow Reynolds number and multiparticle volumetric concentration are also considered. The results show that the particle transport rate is enhanced in some rough fractures at intermediate particle diameter to mechanical aperture ratio values, but further narrowing of the mechanical aperture leads to particle arrest. The evaluations of multiparticle flow and transport also reveal that increased particle interactions result in varied hydraulic aperture values.
GEOMECHANICS FOR ENERGY AND THE ENVIRONMENT
(2022)
Article
Chemistry, Analytical
Hiroshi Yamashita, Takeshi Akinaga, Masako Sugihara-Seki
Summary: The study focused on the effect of Reynolds number on inertial focusing in rectangular duct flows. Numerical simulations were conducted to analyze the lift force on spherical particles in the duct, determining the lift-force distribution map over a wide range of Reynolds numbers. The study identified different particle-focusing patterns based on the duct cross-section shape and Reynolds number, including subcritical pitchfork and supercritical pitchfork bifurcations.
Article
Mathematics, Applied
Ndivhuwo M. Musehane, Madeleine L. Combrinck, Laurent N. Dala
Summary: This paper discusses the standard inertial Navier-Stokes equations and the non-inertial form of the Navier-Stokes equations for the motion of a compressible fluid around an object in arbitrary motion. It introduces an Eulerian approach to derive apparent forces in the non-inertial reference frame and highlights the importance of fictitious work terms in quantifying the heat transfer of an accelerating/decelerating body.
APPLIED MATHEMATICS AND COMPUTATION
(2021)
Article
Computer Science, Interdisciplinary Applications
Junxiang Yang, Zhijun Tan, Junseok Kim
Summary: In this study, an efficient method for solving the incompressible Navier-Stokes equation has been developed, which introduces a time-dependent Lagrange multiplier to transform the equation and designs a second-order time-accurate scheme.
COMPUTERS & FLUIDS
(2022)
Article
Computer Science, Interdisciplinary Applications
Kirill Goncharuk, Oz Oshri, Yuri Feldman
Summary: A novel formulation of the direct forcing immersed boundary (IB) method is presented, which treats it as an integral part of a SIMPLE method for simulating incompressible flows. The incompressibility and no-slip kinematic constraints are treated implicitly as distributed Lagrange multipliers and are fully coupled with each other. The developed methodology shows promising capabilities in simulating shear-and buoyancy-driven confined flows with stationary immersed bodies.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Physics, Applied
Che-Ming Shih, Chun-Fei Kung, Chien-Cheng Chang, Tsorng-Whay Pan
APPLIED PHYSICS LETTERS
(2015)
Article
Physics, Mathematical
Xiting Niu, Lingling Shi, Tsorng-Whay Pan, Roland Glowinski
COMMUNICATIONS IN COMPUTATIONAL PHYSICS
(2015)
Article
Computer Science, Interdisciplinary Applications
Tsorng-Whay Pan, Shihai Zhao, Xiting Niu, Roland Glowinski
JOURNAL OF COMPUTATIONAL PHYSICS
(2015)
Article
Computer Science, Interdisciplinary Applications
Lingling Shi, Suncica Canic, Annalisa Quaini, Tsorng-Whay Pan
JOURNAL OF COMPUTATIONAL PHYSICS
(2016)
Article
Mechanics
Tsorng-Whay Pan, Roland Glowinski
JOURNAL OF NON-NEWTONIAN FLUID MECHANICS
(2017)
Article
Mathematics, Applied
Aixia Guo, Tsorng-Whay Pan, Jiwen He, Roland Glowinski
COMPUTATIONAL METHODS IN APPLIED MATHEMATICS
(2017)
Article
Mathematics
Shihai Zhao, Yao Yu, Tsorng-Whay Pan, Roland Glowinski
CHINESE ANNALS OF MATHEMATICS SERIES B
(2018)
Article
Computer Science, Interdisciplinary Applications
Shang-Huan Chiu, Tsorng-Whay Pan, Roland Glowinski
COMPUTERS & FLUIDS
(2018)
Article
Mechanics
Liang-Hsia Tsai, Chien-Cheng Chang, Tsorng-Whay Pan, Roland Glowinski
INTERNATIONAL JOURNAL OF COMPUTATIONAL FLUID DYNAMICS
(2018)
Article
Mechanics
Tsorng-Whay Pan, Roland Glowinski
Article
Mechanics
Tsorng-Whay Pan, Shang-Huan Chiu, Roland Glowinski
Article
Mechanics
Tsorng-Whay Pan, Ang Li, Roland Glowinski
Summary: This article investigates the equilibrium radial positions of neutrally buoyant balls in circular Poiseuille flows through direct numerical simulations, revealing different equilibrium positions and stability under varying Reynolds numbers. At high Reynolds numbers, a single ball exhibits two equilibrium positions, while a two-ball train becomes unstable at higher Reynolds numbers, showing periodic interactions and exhibiting an unstable phenomenon beyond a critical Reynolds number.
Article
Computer Science, Interdisciplinary Applications
Ang Li, Tsorng-Whay Pan, Roland Glowinski
Summary: This article discusses the simulation of neutrally buoyant particles of non-symmetric shape in non-Newtonian shear-thinning fluids using a Lagrange multiplier based fictitious domain method (DLM/FD). The study compares numerical solutions of steady Poiseuille flow with exact solutions in a two-dimensional channel, and explores the impact of shear-thinning on the movement of a self-propelled swimmer composed of two disks.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS
(2022)
Article
Physics, Fluids & Plasmas
Tsorng-Whay Pan, Roland Glowinski
Article
Computer Science, Interdisciplinary Applications
Tian Liang, Lin Fu
Summary: In this work, a new shock-capturing framework is proposed based on a new candidate stencil arrangement and the combination of infinitely differentiable non-polynomial RBF-based reconstruction in smooth regions with jump-like non-polynomial interpolation for genuine discontinuities. The resulting scheme achieves high order accuracy and resolves genuine discontinuities with sub-cell resolution.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Lukas Lundgren, Murtazo Nazarov
Summary: In this paper, a high-order accurate finite element method for incompressible variable density flow is introduced. The method addresses the issues of saddle point system and stability problem through Schur complement preconditioning and artificial compressibility approaches, and it is validated to have high-order accuracy for smooth problems and accurately resolve discontinuities.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Gabriele Ciaramella, Laurence Halpern, Luca Mechelli
Summary: This paper presents a novel convergence analysis of the optimized Schwarz waveform relaxation method for solving optimal control problems governed by periodic parabolic PDEs. The analysis is based on a Fourier-type technique applied to a semidiscrete-in-time form of the optimality condition, which enables a precise characterization of the convergence factor at the semidiscrete level. The behavior of the optimal transmission condition parameter is also analyzed in detail as the time discretization approaches zero.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Jonas A. Actor, Xiaozhe Hu, Andy Huang, Scott A. Roberts, Nathaniel Trask
Summary: This article introduces a scientific machine learning framework that uses a partition of unity architecture to model physics through control volume analysis. The framework can extract reduced models from full field data while preserving the physics. It is applicable to manifolds in arbitrary dimension and has been demonstrated effective in specific problems.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Nozomi Magome, Naoki Morita, Shigeki Kaneko, Naoto Mitsume
Summary: This paper proposes a novel strategy called B-spline based SFEM to fundamentally solve the problems of the conventional SFEM. It uses different basis functions and cubic B-spline basis functions with C-2-continuity to improve the accuracy of numerical integration and avoid matrix singularity. Numerical results show that the proposed method is superior to conventional methods in terms of accuracy and convergence.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Timothy R. Law, Philip T. Barton
Summary: This paper presents a practical cell-centred volume-of-fluid method for simulating compressible solid-fluid problems within a pure Eulerian setting. The method incorporates a mixed-cell update to maintain sharp interfaces, and can be easily extended to include other coupled physics. Various challenging test problems are used to validate the method, and its robustness and application in a multi-physics context are demonstrated.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Xing Ji, Fengxiang Zhao, Wei Shyy, Kun Xu
Summary: This paper presents the development of a third-order compact gas-kinetic scheme for compressible Euler and Navier-Stokes solutions, constructed particularly for an unstructured tetrahedral mesh. The scheme demonstrates robustness in high-speed flow computation and exhibits excellent adaptability to meshes with complex geometrical configurations.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Alsadig Ali, Abdullah Al-Mamun, Felipe Pereira, Arunasalam Rahunanthan
Summary: This paper presents a novel Bayesian statistical framework for the characterization of natural subsurface formations, and introduces the concept of multiscale sampling to localize the search in the stochastic space. The results show that the proposed framework performs well in solving inverse problems related to porous media flows.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Jacob Rains, Yi Wang, Alec House, Andrew L. Kaminsky, Nathan A. Tison, Vamshi M. Korivi
Summary: This paper presents a novel method called constrained optimized DMD with Control (cOptDMDc), which extends the optimized DMD method to systems with exogenous inputs and can enforce the stability of the resulting reduced order model (ROM). The proposed method optimally places eigenvalues within the stable region, thus mitigating spurious eigenvalue issues. Comparative studies show that cOptDMDc achieves high accuracy and robustness.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Andrea La Spina, Jacob Fish
Summary: This work introduces a hybridizable discontinuous Galerkin formulation for simulating ideal plasmas. The proposed method couples the fluid and electromagnetic subproblems monolithically based on source and employs a fully implicit time integration scheme. The approach also utilizes a projection-based divergence correction method to enforce the Gauss laws in challenging scenarios. Numerical examples demonstrate the high-order accuracy, efficiency, and robustness of the proposed formulation.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Junhong Yue, Peijun Li
Summary: This paper proposes two numerical methods (IP-FEM and BP-FEM) to study the flexural wave scattering problem of an arbitrary-shaped cavity on an infinite thin plate. These methods successfully decompose the fourth-order plate wave equation into the Helmholtz and modified Helmholtz equations with coupled conditions on the cavity boundary, providing an effective solution to this challenging problem.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
William Anderson, Mohammad Farazmand
Summary: We develop fast and scalable methods, called RONS, for computing reduced-order nonlinear solutions. These methods have been proven to be highly effective in tackling challenging problems, but become computationally prohibitive as the number of parameters grows. To address this issue, three separate methods are proposed and their efficacy is demonstrated through examples. The application of RONS to neural networks is also discussed.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Marco Caliari, Fabio Cassini
Summary: In this paper, a second order exponential scheme for stiff evolutionary advection-diffusion-reaction equations is proposed. The scheme is based on a directional splitting approach and uses computation of small sized exponential-like functions and tensor-matrix products for efficient implementation. Numerical examples demonstrate the advantage of the proposed approach over state-of-the-art techniques.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Sebastiano Boscarino, Seung Yeon Cho, Giovanni Russo
Summary: This work proposes a high order conservative semi-Lagrangian method for the inhomogeneous Boltzmann equation of rarefied gas dynamics. The method combines a semi-Lagrangian scheme for the convection term, a fast spectral method for computation of the collision operator, and a high order conservative reconstruction and a weighted optimization technique to preserve conservative quantities. Numerical tests demonstrate the accuracy and efficiency of the proposed method.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Jialei Li, Xiaodong Liu, Qingxiang Shi
Summary: This study shows that the number, centers, scattering strengths, inner and outer diameters of spherical shell-structured sources can be uniquely determined from the far field patterns. A numerical scheme is proposed for reconstructing the spherical shell-structured sources, which includes a migration series method for locating the centers and an iterative method for computing the inner and outer diameters without computing derivatives.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
