Article
Mathematics, Applied
Xiaochen Chu, Chuanjun Chen, Tong Zhang
Summary: In this paper, a two-level stabilized finite volume method is developed and analyzed for the steady incompressible magnetohydrodynamic (MHD) equations. The method uses linear polynomial space to approximate the velocity, pressure, and magnetic fields, and introduces two local Gauss integrations to overcome the restriction of discrete inf-sup condition. The existence and uniqueness of the solution of the discrete problem are proved, and optimal error estimates of numerical solutions in H-1 and L-2-norms are established. The stability and convergence of the method for the stationary incompressible MHD equations are also provided.
NUMERICAL METHODS FOR PARTIAL DIFFERENTIAL EQUATIONS
(2023)
Article
Computer Science, Interdisciplinary Applications
Igor Sokolov, Haomin Sun, Gabor Toth, Zhenguang Huang, Valeriy Tenishev, Lulu Zhao, Jozsef Kota, Ofer Cohen, Tamas I. Gombosi
Summary: In this paper, a finite volume scheme based on integral relation for Poisson brackets is proposed to solve the Liouville equation, which conserves the number of particles, maintains the total-variation-diminishing (TVD) property, and provides high-quality numerical results. The proposed scheme can be used to solve other types of kinetic equations, including the transport equations describing the acceleration and propagation of Solar Energetic Particles (SEPs), which is of practical importance due to radiation hazards. The scheme is demonstrated to be accurate and efficient, making it applicable to global simulation systems analyzing space weather.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Environmental Sciences
Chunjian Sun, Anmin Zhang, Baogang Jin, Xidong Wang, Xiaoshuang Zhang, Lianxin Zhang
Summary: The seasonality of eddy kinetic energy in the north Indian Ocean is analyzed, and the study identifies the regions with significant eddy energy and the factors contributing to its variation.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Physics, Applied
Noor Muhammad, Khalid Abdulkhaliq M. Alharbi
Summary: This paper utilizes a Large Eddy Simulation (LES) computational model to study turbulence flow on a spillway with four inlets and a single outlet. By calculating parameters such as kinetic energy, fluctuated velocity, mean velocity, and pressure, the turbulent flow is analyzed.
INTERNATIONAL JOURNAL OF MODERN PHYSICS B
(2023)
Article
Computer Science, Interdisciplinary Applications
Hongyang Luo, John G. Lyon, Binzheng Zhang
Summary: In many astrophysical plasmas, anisotropic temperature is observed due to insufficient Coulomb collision. To describe such plasma system, anisotropic pressure MHD models are needed. A robust Gas-Kinetic flux scheme is developed to numerically solve the anisotropic MHD equation. The scheme performs well for both linear wave and non-linear MHD problems.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Thermodynamics
Aritra Roy Choudhury, Kameswararao Anupindi
Summary: In this study, a planar turbulent offset wall-jet with heat transfer is numerically investigated using large-eddy simulation (LES). The flow characteristics, thermal characteristics, and turbulent kinetic energy of the jet are analyzed. The evolution of Nusselt number on the wall exhibits three distinct peaks correlated with the change-of-sign of the wall skin-friction coefficient. The flow domain can be categorized into recirculation, impingement, and wall-jet regions, and distinct flow and thermal characteristics are observed in different regions.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Astronomy & Astrophysics
Kuangxu Chen, Chunlei Liang
Summary: This paper presents a method that combines high-order spectral difference method with divergence cleaning for accurate simulations on curved unstructured grids. The method can achieve arbitrarily high accuracy in spatial discretization and is able to capture details of shock interfaces and small-scale vortex structures.
ASTROPHYSICAL JOURNAL
(2022)
Article
Engineering, Mechanical
Suhaib Ardah, Francisco J. Profito, Daniele Dini
Summary: This paper proposes an integrated finite-volume framework for solving thermal elasto-hydrodynamic lubrication problems and predicts the lubrication performance of non-conformal contacts. By considering fluid flow effects and thermal behavior, the framework is able to handle strong nonlinearity and improve convergence of the results.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Mechanics
Huijie Wu, Binbin Wang
Summary: We analyzed the turbulence kinetic energy (TKE) budget in a bubble plume using particle image velocimetry with fluorescent particles. Our findings confirmed the presence of an inverse energy cascade in the bubble plume, with TKE being transferred from small to large eddies. This is due to direct injection of TKE by bubble passages across different scales, rather than shear production in large scales. Turbulence dissipation was identified as the primary sink for the TKE produced by the bubbles. By decomposing velocities based on the critical length scale of energy transfer, we were able to distinguish between large- and small-scale motions in the bubble plume. The large-scale motions exhibited a skewed distribution and were likely associated with the return flow after bubble passage and the velocities induced by the bubble wake. The small-scale motions followed a Gaussian distribution relatively well.
Article
Meteorology & Atmospheric Sciences
Jinhui Yang, Jianping Wu, Junqiang Song, Jun Peng, Fukang Yin, Hongze Leng, Kaijun Ren
Summary: YHGSM-FVM is an extension of YHGSM model, which uses the finite-volume method to compute horizontal derivatives in grid-point space, improving computational efficiency. Compared to YHGSM, YHGSM-FVM outperforms in computational efficiency while maintaining comparable prediction skill.
QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY
(2023)
Article
Computer Science, Interdisciplinary Applications
G. Capdeville
Summary: We propose a new method for incorporating more physics into the flux function of a finite-volume solver for compressible Navier-Stokes equations. This method serves as an alternative approach to classical approximate Riemann solvers. The novelty lies in the use of the gas distribution function derived from the Boltzmann equation with a simplified collision source term, which is then utilized to compute the cell interface flux. Two solutions are explored for computing the distribution function, resulting in the simple gas kinetic scheme and the acoustic gas kinetic scheme. Both schemes are investigated and analyzed in various test cases, including inviscid/viscous and steady/unsteady problems.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Computer Science, Interdisciplinary Applications
Yizhao Wan, Nengyou Wu, Qiang Chen, Wentao Li, Gaowei Hu, Li Huang, Weiping Ouyang
Summary: This paper presents a THMC coupled model for simulating fluid flow and geomechanical behavior in hydrate-bearing sediments. A new numerical method based on the hybrid CVFEM-FEM is developed and tested for accuracy and reliability.
COMPUTERS AND GEOTECHNICS
(2022)
Article
Thermodynamics
Zhangyan Zhao, Mengke Wen, Weidong Li
Summary: This study introduces a coupled gas kinetic BGK scheme based on the finite volume lattice Boltzmann method for nearly incompressible thermal flows. The method determines fluxes analytically to reduce numerical dissipation and adopts implicit collision for efficiency improvement. Numerical results confirm the accuracy and reliability of the proposed scheme.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Engineering, Marine
Mahta Samie, Seyed Hossein Mohajeri, Seyed Abbas Hosseini, Mojtaba Mehraein
Summary: This study numerically examined the performance of an in-stream hydro-kinetic turbine and its impacts on a simplified river channel flow. The results showed that the turbine installation location significantly affects the natural flow structure of the compound channel, while having minimal effects on the bed shear stress. Installing the turbine at the interaction zone of the compound open-channel yielded the highest maximum power coefficient.
Article
Computer Science, Interdisciplinary Applications
Mengke Wen, Yu Wang, Weidong Li, Zhangyan Zhao
Summary: This work improves the recently proposed gas kinetic Bhatnagar-Gross-Krook (BGK) scheme for finite volume lattice Boltzmann method (FVLBM) to enhance numerical stability. Two striking features are introduced in the present improved method: the introduction of two auxiliary distribution functions, (f) over bar (alpha) and (f) over tilde (alpha), with collision effect included, and the application of an auxiliary distribution function (f) over tilde (alpha) to the reconstructed fluxes on the cell interfaces. These features enhance the numerical stability of the method and allow for higher Delta t/tau compared to the original scheme.
COMPUTERS & FLUIDS
(2023)
Article
Computer Science, Interdisciplinary Applications
Jacobus D. Brandsen, Axelle Vire, Sergio R. Turteltaub, Gerard J. W. Van Bussel
Summary: This paper evaluates the penalty and Lagrange multiplier methods for enforcing the no-slip condition in fluid-structure interaction simulations. The Lagrange multiplier method provides accurate solutions without parameter tuning, but at a higher computational cost. The penalty method can achieve similar accuracy, but requires selecting the appropriate penalty factor.
ENGINEERING COMPUTATIONS
(2021)
Article
Green & Sustainable Science & Technology
Jing Dong, Axelle Vire
Summary: This study aims to predict the occurrence of the vortex ring state (VRS) during the operation of floating offshore wind turbines, and the results show that VRS may occur for a wide range of operating conditions. The most suitable criterion for VRS prediction is found to be Wolkovitch's criterion.
Article
Engineering, Mechanical
Ze Lyu, Thomas Boeck, Christian Karcher
Summary: Experimental results show that the force sensor can detect a moving particle in a quiescent conducting liquid. The structure of the Fx signal can be reproduced with less variation and is less sensitive to the Reynolds number than the Fz signal. Furthermore, the structure and magnitude of time-dependent Lorentz force signals can be reasonably predicted by a numerical model.
EXPERIMENTS IN FLUIDS
(2021)
Article
Computer Science, Interdisciplinary Applications
Julia Steiner, Richard P. Dwight, Axelle Vire
Summary: The article introduces a systematic data-driven approach to deriving new Reynolds-Averaged Navier-Stokes (RANS) models in the wind-energy setting, showing significantly improved predictions compared to baseline models. Time-averaged LES data is used as ground-truth to derive optimal corrective fields for turbulence effects, and a custom RANS closure is built using deterministic symbolic regression to improve predictions for mean velocity and turbulence kinetic energy fields.
COMPUTERS & FLUIDS
(2022)
Article
Energy & Fuels
Lu Wang, Amy Robertson, Jason Jonkman, Jang Kim, Zhi-Rong Shen, Arjen Koop, Adria Borras Nadal, Wei Shi, Xinmeng Zeng, Edward Ransley, Scott Brown, Martyn Hann, Pranav Chandramouli, Axelle Vire, Likhitha Ramesh Reddy, Xiang Li, Qing Xiao, Beatriz Mendez Lopez, Guillen Campana Alonso, Sho Oh, Hamid Sarlak, Stefan Netzband, Hyunchul Jang, Kai Yu
Summary: This study investigates the feasibility of using computational fluid dynamics (CFD) simulations to tune mid-fidelity models in floating offshore wind systems. The simulations are validated against experimental results, and reasonable agreement is found between the two. The linear and quadratic damping coefficients have large numerical uncertainties, while the equivalent damping ratios are consistently predicted with lower uncertainty.
Article
Energy & Fuels
Axelle Vire, Geert Lebesque, Mikko Folkersma, Roland Schmehl
Summary: This paper presents steady-state RANS simulations for a leading-edge inflatable (LEI) wing, exploring its aerodynamic performance and local flow characteristics. The results show that side-slip has a negative impact on the wing's aerodynamic performance, while the chordwise struts have little influence.
Article
Green & Sustainable Science & Technology
Jing Dong, Axelle Vire, Zhangrui Li
Summary: This paper conducts a comparative analysis and evaluation of the vortex ring state (VRS) phenomenon and aerodynamic performance of a floating offshore wind turbine (FOWT), and compares the results with other similar studies, providing a deeper understanding of the working state changes of FOWTs.
Article
Thermodynamics
Julia Steiner, Axelle Vire, Richard P. Dwight
Summary: Data-driven RANS turbulence closures are considered a viable option in wind energy. Parsimonious models have advantages in terms of stability, interpretability, and execution speed. Model corrections need to be made only in limited regions, and introducing a classifier helps identify these regions.
FLOW TURBULENCE AND COMBUSTION
(2022)
Article
Engineering, Mechanical
Thomas Boeck, Seyed Loghman Sanjari, Tatiana Becker
Summary: The article studies the behavior of vertically driven pendulum with additional electromagnetic interaction caused by eddy currents in a nearby thick conducting plate. The motion equation of the pendulum is derived and the conditions for equilibrium instability are obtained. Numerical analysis shows that strong electromagnetic interaction leads to significant differences between analytical and numerical results, and the area of harmonic instability can become doubly connected. Chaotic motions can also occur under moderately strong driving.
NONLINEAR DYNAMICS
(2022)
Article
Green & Sustainable Science & Technology
Jing Dong, Axelle Vire
Summary: This paper investigates the working state changes of the rotor in floating offshore wind turbines with platform motions, and quantitatively and visually evaluates them using an aerodynamic model. The results show that the rotor experiences alternating windmill, vortex ring, and propeller states during a full cycle of the surge motion of the floating platform, with the vortex ring state being the most unstable.
Article
Energy & Fuels
Manuel Rentschler, Pranav Chandramouli, Guilherme Vaz, Axelle Vire, Rodolfo T. Goncalves
Summary: With the advancement of high-performance computation capabilities, high-fidelity modelling tools such as computational fluid dynamics are increasingly used in the offshore renewable sector. This work compares the results of two different CFD codes, OpenFOAM and ReFRESCO, with water tank experiments. The study finds that both codes accurately model the natural period of the decay simulations but are overly dissipative in terms of damping. Differences between the codes are revealed through flow field analysis.
JOURNAL OF OCEAN ENGINEERING AND MARINE ENERGY
(2023)
Article
Mechanics
Shashwat Bhattacharya, Thomas Boeck, Dmitry Krasnov, Joerg Schumacher
Summary: We investigate how fringing magnetic fields affect turbulent thermal convection in a horizontally extended rectangular domain. By controlling the gap between the magnetic poles and the convection cell, we vary the fringe width and observe the changes in large-scale structures and heat transport. We find that as the local vertical magnetic field strength increases, the structures become thinner and align perpendicular to the sidewalls.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Engineering, Marine
Hiromasa Otori, Yuka Kikuchi, Irene Rivera-Arreba, Axelle Vire
Summary: The hydrodynamic coefficients are evaluated using fully nonlinear Navier-Stokes forced oscillation simulations with the volume of fluid method. Richardson extrapolation is used to obtain grid-independent solutions. The predicted hydrodynamic coefficients are validated through water tank tests. The drag coefficient models' applicability for a barge-type floater is investigated by comparing with numerically predicted drag coefficients for different Keulegan-Carpenter numbers in the surge and heave directions. Dynamic response analyses are then performed using the engineering model with the validated drag coefficient models. The results show that considering drag forces leads to better agreement with measurements, especially in high wave conditions.
Article
Green & Sustainable Science & Technology
Axelle Vire, Bruce LeBlanc, Julia Steiner, Nando Timmer
Summary: This experimental study focuses on the addition of a passive slat on a thick airfoil typically used in the inboard part of commercial wind turbine blades. The results show that the presence of a slat can increase the lift-to-drag ratio of the airfoil, especially for clean airfoil and small angles of attack.
WIND ENERGY SCIENCE
(2022)
Article
Green & Sustainable Science & Technology
Carlos Ferreira, Wei Yu, Arianna Sala, Axelle Vire
Summary: This study investigates the large surge motions and blade-vortex interaction phenomenon of floating offshore wind turbines. The findings show that the actuator disc momentum theory and the blade element momentum theory are valid and accurate in predicting the induction at the actuator in surge, even for large and fast motions.
WIND ENERGY SCIENCE
(2022)
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)