Article
Computer Science, Interdisciplinary Applications
Brandon Gusto, Tomasz Plewa
Summary: This study introduces a novel hybrid adaptive multiresolution (HAMR) approach to AMR-based calculations, which addresses the issue of unnecessarily high mesh resolution in regions adjacent to important solution features. By utilizing multiresolution smoothness indicators, the computational cost of individual physics solvers can be decreased through interpolation in smooth regions, resulting in improved performance of AMR codes.
COMPUTER PHYSICS COMMUNICATIONS
(2022)
Article
Computer Science, Interdisciplinary Applications
Jianqiang Xie, Dong Liang, Zhiyue Zhang
Summary: In this paper, two types of new energy-preserving local mesh-refined splitting finite difference time-domain (EP-LMR-S-FDTD) schemes for two-dimensional Maxwell's equations are developed and analyzed. Efficient local interface schemes are proposed based on energy analysis to ensure energy conservation, spatial high accuracy, and avoid oscillations. The EP-LMR-S-FDTD schemes are implemented with a fast approach, solving unknowns on a line-structure before on an inverted U-form structure, proving energy preservation, unconditional stability, convergence, and obtaining error estimates. Numerical experiments confirm the performance of the EP-LMR-S-FDTD schemes.
JOURNAL OF COMPUTATIONAL PHYSICS
(2021)
Article
Computer Science, Interdisciplinary Applications
S. Polak, X. Gao
Summary: This work presents the development of a multi-fluid plasma modeling capability based on a parallel, adaptive, fourth-order finite-volume method in computational fluid dynamics. The model couples the governing equations derived from the moments of the Boltzmann equation with Maxwell's equations, considering local thermodynamic equilibrium. The accuracy and efficiency of the algorithm are verified using problems with exact solutions, and it is shown that the multi-fluid model provides accurate solutions with half the cell count compared to traditional 2nd-order methods. Additionally, successful application of adaptive mesh refinement is demonstrated, resulting in a significant reduction in mesh size for plasma simulations.
COMPUTER PHYSICS COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Jia-Jie Feng, Jia-Nan Chen, Wei Kang, Yun-Dong Wu
Summary: This study systematically investigated protein loop structure prediction using a large number of MD simulations, revealing that the recently developed RSFF2C force field performed the best in accurately predicting 12 out of 15 long loops. High-temperature MD simulations were also explored as a cost-effective alternative, with comparable results to REMD simulations observed for the RSFF2C+TIP3P force field. Enhanced sampling techniques, such as replica exchange, with the RSFF2C force field, show promise for accurate loop structure prediction.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2021)
Article
Computer Science, Interdisciplinary Applications
Chun Shen, Shuming Gao, Rui Wang
Summary: This paper introduces a physics-based hexahedral mesh adaptation method based on posterior-error estimation. It determines the refined regions based on analysis results and uses a graph cuts algorithm to determine the quad sets to be inserted. The mesh quality is improved through a size-preserving mesh optimization method. Experimental results confirm the effectiveness of the proposed method.
ENGINEERING WITH COMPUTERS
(2022)
Article
Computer Science, Interdisciplinary Applications
Roch Smets, Nicolas Aunai, Andrea Ciardi, Matthieu Drouin, Martin Campos-Pinto, Philip Deegan
Summary: Particle-In-Cell codes are widely used in plasma physics simulations, and often require particle splitting for improved statistics or to avoid fictitious self-forces on non-uniform meshes. Existing splitting methods are mainly empirical and lack quantitative evaluation on distribution function preservation. This study introduces a new method specifically for adaptive mesh refinement codes, minimizing the distance between original and split particle assignment functions. The method incurs no additional computing time and approaches the exact solution with a sufficient number of split particles.
COMPUTER PHYSICS COMMUNICATIONS
(2021)
Article
Computer Science, Interdisciplinary Applications
Khuong D. Nguyen, Cuong-Le Thanh, H. Nguyen-Xuan, M. Abdel-Wahab
Summary: Porosity has been studied for its effect on crack propagation in functionally graded materials (FGM) structures, using a hybrid phase-field approach. The study showed that using a local refinement multi-patch algorithm based on the Virtual Uncommon-Knot-Inserted Master-Slave (VUKIMS) technique in the framework of isogeometric analysis (IGA) can significantly reduce the computational cost, while achieving the desired accuracy with cubic NURBS elements.
ENGINEERING WITH COMPUTERS
(2023)
Article
Computer Science, Interdisciplinary Applications
Songzhe Xu, Boshun Gao, Alec Lofquist, Milinda Fernando, Ming-Chen Hsu, Hari Sundar, Baskar Ganapathysubramanian
Summary: This paper presents a scalable, adaptively refined, octree-based finite element approach with immersogeometric analysis for tracking particle migration in microchannels. The method utilizes a parallel, hierarchically refined octree mesh and variational immersogeometric formulation for efficient particle motion tracking. Good scalability and validation results are achieved for a benchmark case, demonstrating the potential of the proposed approach for tracking particle motion in complex channel flows.
COMPUTERS & FLUIDS
(2021)
Article
Multidisciplinary Sciences
Dong Xu, Jianing Liu, Yunfeng Wu, Chunning Ji
Summary: We propose a simple and generalized Discretized Immersed Boundary Method (DIBM) that significantly improves efficiency by discretizing the interpolation functions and reusing a predefined universal interpolation stencil. DIBM achieves speedup ratios of 30-40 or even higher compared to conventional Immersed Boundary Method (IBM), with estimated errors below 1%.
SCIENTIFIC REPORTS
(2023)
Article
Engineering, Marine
Jan Geese, Julian Kimmerl, Marc Nadler, Moustafa Abdel-Maksoud
Summary: This study investigates the usability and practicability of automatic adaptive mesh refinement (AMR) in computational fluid dynamics simulations. The study focuses on the computational effort required for high frequency updating AMR and finds that AMR is suitable for resolving cavities with relative motion to the propeller and in interaction with slipstream obstacles. However, the computation time is significantly increased and there may be numerical instabilities.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Computer Science, Interdisciplinary Applications
Zihao Cheng, Anthony Wachs
Summary: We propose an immersed boundary/multi-relaxation time lattice Boltzmann method for particle-resolved simulation of particle-laden flows. The method handles the no-slip boundary condition using an explicit feedback immersed boundary method and employs a smoothed discrete delta function and a multi-relaxation time collision operator for improved stability and accuracy. The method is extended to adaptive quadtree/octree grids and implemented in the open-source software Basilisk, achieving high computational efficiency and accuracy in a variety of validation cases.
JOURNAL OF COMPUTATIONAL PHYSICS
(2022)
Article
Astronomy & Astrophysics
Tzihong Chiueh, Yi-Hsiung Hsu
Summary: Soliton in the turbulent wave dark matter halo of a galaxy exhibits various excitation modes and heavy breathing under stress. A theory of collective excitation for a dark matter soliton is proposed, considering the coupling to negative energy modes. The frequencies and mode structures of small-amplitude perturbations are assessed using a constrained variational principle, showing good agreement with simulation data.
Article
Physics, Fluids & Plasmas
Brandon E. Morgan
Summary: High-fidelity large-eddy simulations were conducted to study Rayleigh-Taylor mixing in three different configurations involving gravity reversal. The results showed a deficiency in a commonly used transport equation for mass-flux velocity, which could lead to significant errors in predicting mixing layer growth after gravity reversal. An alternative formulation for this equation was proposed to capture the stabilization effect more accurately.
Article
Astronomy & Astrophysics
Milinda Fernando, David Neilsen, Yosef Zlochower, Eric W. Hirschmann, Hari Sundar
Summary: We present results from the new Dendro-GR code, which includes simulations of binary black hole mergers for mass ratios up to q = 16. The code utilizes wavelet adaptive multiresolution and an octree-based data structure to generate an unstructured grid adapted to the spacetime geometry. Validation of the code is achieved through comparisons to LazEv, demonstrating good scaling, improved convergence properties, and efficient usage of computational resources.
Article
Mathematics, Applied
Johannes Holke, David Knapp, Carsten Burstedde
Summary: In this work, we discuss parallel algorithms for computing the ghost layer in computational, distributed memory, recursively adapted meshes. The ghost layer is necessary for executing parallel, element-based computer simulations. We present a design with modularity of algorithms and data structures, targeting adaptive, nonconforming forest-of-trees meshes with mixed element shapes like cubes, prisms, and tetrahedra.
SIAM JOURNAL ON SCIENTIFIC COMPUTING
(2021)
Article
Astronomy & Astrophysics
Apurva Oza, Francois Leblanc, Robert E. Johnson, Carl Schmidt, Ludivine Leclercq, Timothy A. Cassidy, Jean-Yves Chaufray
PLANETARY AND SPACE SCIENCE
(2019)
Article
Astronomy & Astrophysics
Philippe Zarka, Di Li, Jean-Mathias Griessmeier, Laurent Lamy, Julien N. Girard, Sebastien L. G. Hess, T. Joseph W. Lazio, Gregg Hallinan
RESEARCH IN ASTRONOMY AND ASTROPHYSICS
(2019)
Article
Astronomy & Astrophysics
C. K. Louis, S. L. G. Hess, B. Cecconi, P. Zarka, L. Lamy, S. Aicardi, A. Loh
ASTRONOMY & ASTROPHYSICS
(2019)
Article
Geosciences, Multidisciplinary
A. Martinez, F. Leblanc, J. Y. Chaufray, R. Modolo, O. Witasse, Y. Dong, T. Hara, J. Halekas, R. Lillis, J. McFadden, F. Eparvier, L. Leclercq, J. Luhmann, S. Curry, D. Titov, B. Jakosky
GEOPHYSICAL RESEARCH LETTERS
(2019)
Article
Astronomy & Astrophysics
G. Carnielli, M. Goland, F. Leblanc, L. Leclercq, R. Modolo, A. Beth, H. L. F. Huybrighs, X. Jia
Article
Physics, Fluids & Plasmas
J. -C. Mateo-Velez, M. Belhaj, S. Dadouch, P. Sarrailh, S. L. G. Hess, D. Payan
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2019)
Article
Physics, Fluids & Plasmas
P. Oudayer, L. Monnin, J. -C. Mateo-Velez, S. L. G. Hess, P. Sarrailh, G. Murat, J. -F. Roussel
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2019)
Article
Astronomy & Astrophysics
Hayley N. Williamson, Robert E. Johnson, Ludivine Leclercq, Meredith K. Elrod
Article
Astronomy & Astrophysics
Ludivine Leclercq, Hayley N. Williamson, Robert E. Johnson, Orenthal J. Tucker, Lucia Tian, Darci Snowden
Article
Astronomy & Astrophysics
M. K. G. Holmberg, F. Cipriani, T. Nilsson, S. Hess, H. L. F. Huybrighs, L. Z. Hadid, G. Deprez, R. J. Wilson, M. W. Morooka, M. Felici
Summary: In this study, simulations using SPIS were used to analyze the characteristics of the Cassini ion wake and its impact on LP measurements. The results showed a strong agreement between simulated ion densities and LP data, suggesting SPIS as a useful tool for LP data analysis when spacecraft properties and environmental parameters are known. Additionally, the simulations provided constraints on ion temperature estimates in Saturn's inner magnetosphere.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2021)
Article
Physics, Applied
L. Monnin, S. L. G. Hess, J-F Roussel, P. Sarrailh, D. Payan
Summary: A plasma expansion model was developed to study flash-over propagation on spacecraft solar panels, considering plasma extinction effects. A minimum on the sheath potential was found, explaining the end of plasma emission by the cathode and the end of plasma expansion. Numerical results showed good agreement with experimental measurements, and the model has potential applications in preventing arcing on spacecrafts solar panels.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Astronomy & Astrophysics
Iannis Dandouras, Matt G. G. T. Taylor, Johan De Keyser, Yoshifumi Futaana, Ruth A. Bamford, Graziella Branduardi-Raymont, Jean-Yves Chaufray, Dragos Constantinescu, Elisabetta De Angelis, Pierre Devoto, Jonathan Eastwood, Marius Echim, Philippe Garnier, Benjamin Grison, David Hercik, Helmut Lammer, Andre Laurens, Francois Leblanc, Anna Milillo, Rumi Nakamura, Lubomir Prech, Elias Roussos, Stepan Stverak, Julien Forest, Arnaud Trouche, Sebastien L. G. Hess, Jean-Charles Mateo-Velez, James Carpenter, Josef Winter
Summary: The Lunar Orbital Platform - Gateway (LOP-Gateway), assembled and operated by NASA and international partner organizations, offers new opportunities for scientific research in the vicinity of the Moon. It provides a unique location to study the deep space plasma environment and its interaction with the lunar surface and exosphere. This paper explores the potential of externally mounted payloads on the Gateway for space plasma physics research and the impact of the space environment on an inhabited platform.
FRONTIERS IN ASTRONOMY AND SPACE SCIENCES
(2023)
Article
Physics, Fluids & Plasmas
Sebastien L. G. Hess, Denis Payan, Pierre Sarrailh
Summary: Spacecraft can be charged when they come into contact with charged particles in space. The charging is influenced by the surface materials and their exposure to space, resulting in different charging levels for different parts of the spacecraft. The charging on solar panels is especially important due to the polarized elements and small distances between them, leading to strong electric fields and electrostatic discharges (ESDs). This article focuses on controlling the onset of ESDs by studying the impact of cover glass secondary emission properties on the voltage threshold of solar cell ESDs. Numerical simulations using the spacecraft plasma interaction software (SPIS)-ESD software are conducted, as practical experimental studies are not feasible due to the natural variability of physical samples and the lack of materials with controlled characteristics.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2023)
Article
Physics, Fluids & Plasmas
Sebastien L. G. Hess, Ludivine Leclercq
Summary: The article discusses the importance and challenges of modeling spacecraft surface interactions with space environments. It introduces the ChaMISEn data management system developed by ONERA, which provides a convenient way to describe and use the characteristics of space materials. The system includes an open-source data model, extraction software, distributed databases, and libraries. The article also presents use cases related to spacecraft charging modeling to illustrate the capabilities of the system.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2023)
Article
Multidisciplinary Sciences
Emilie Mauduit, Philippe Zarka, Laurent Lamy, Sebastien L. G. Hess
Summary: Radio detection at high time-frequency resolutions is an effective method to study electron acceleration processes, and radio bursts from Jupiter have characteristics that make them easier to detect than slowly variable emissions. In addition to Io-Jupiter S-bursts, drifting radio bursts related to Ganymede-Jupiter interaction and Jovian aurora were found, showing ubiquitous Alfvenic electron acceleration in Jupiter's high-latitude regions.
NATURE COMMUNICATIONS
(2023)
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)