Article
Computer Science, Interdisciplinary Applications
Tianju Xue, WaiChing Sun, Sigrid Adriaenssens, Yujie Wei, Chuanqi Liu
Summary: An efficient method for reinitializing a level set function to a signed distance function using the finite element method is proposed in this study. By applying modified boundary conditions weakly with a penalty method, the original zero level set interface is preserved. Numerical benchmarks show optimal convergence rates under different error measures, demonstrating the accuracy and robustness of the method for complex geometries.
JOURNAL OF COMPUTATIONAL PHYSICS
(2021)
Article
Mathematics, Applied
Mario Santilli
Summary: The paper explores the denseness of the singular set of the distance function from a C-1-hypersurface and tackles the issue of the existence of viscosity solutions for the Eikonal equation where the singular set is not no-where dense.
COMMUNICATIONS IN PARTIAL DIFFERENTIAL EQUATIONS
(2021)
Article
Mechanics
S. Parameswaran, J. C. Mandal
Summary: This paper presents a novel reinitialization approach for the conservative level set method, addressing the drawbacks of existing methods and reducing the numerical computations. The effectiveness of the proposed approach is demonstrated through various test problems, and its ability to deal with complex mesh types is also shown.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2023)
Article
Computer Science, Interdisciplinary Applications
Changxiao Shao, Shian Yuan, Min Chai, Tai Jin, Kun Luo
Summary: A generalized variational level set method without frequent reinitialization process is proposed to improve the traditional level set method for detailed numerical simulations of gas liquid flows. By adding a penalty term in the classical level set advection equation, the need for frequent reinitialization is reduced, resulting in more accurate and efficient simulations.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Computer Science, Interdisciplinary Applications
Felix Henri, Mathieu Coquerelle, Pierre Lubin
Summary: A robust and high order reinitialization strategy in a level set framework is introduced with the RCP method and a new algorithm for detecting ill-defined points, leading to improved accuracy and robustness of level set methods.
JOURNAL OF COMPUTATIONAL PHYSICS
(2022)
Article
Mathematics, Applied
Shingyu Leung, Jianliang Qian, Jiangtao Hu
Summary: The proposed method efficiently tackles the first-arrival traveltime tomography problem in irregular domains using a PDE-based approach, with innovations in fast sweeping and singularity removal.
SIAM JOURNAL ON SCIENTIFIC COMPUTING
(2021)
Article
Mathematics, Applied
A. Karakus, N. Chalmers, T. Warburton
Summary: This paper presents a level set reinitialization technique based on a high-order, local discontinuous Galerkin method on unstructured triangular meshes. By discretizing the time flow Eikonal equation, the method achieves improved stability and convergence speed, especially for banded level set formulations.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2022)
Article
Mathematics, Interdisciplinary Applications
P. Areias, N. Sukumar, J. Ambrosio
Summary: We propose a PDE-based node-to-element contact formulation as an alternative to traditional geometric formulations. By constructing an approximate distance function (ADF) to the boundaries of solid objects, we achieve solutions to nonsmooth contact problems with continuous gaps using finite element discretizations. The ADF does not depend on the number of objects and a single solution of the partial differential equation uniquely defines the contact conditions for all incident points in the mesh.
COMPUTATIONAL MECHANICS
(2023)
Article
Mathematics, Applied
Michael Quell, Georgios Diamantopoulos, Andreas Hoessinger, Josef Weinbub
Summary: In this study, the multi-mesh fast marching method is extended by a block-based decomposition step to enhance serial and parallel performance on hierarchical meshes. The approach offers improved load balancing with a high mesh partitioning degree, effectively balancing mesh partitions with varying sizes. Various benchmarks and parameter studies are conducted on representative geometries with different complexities, resulting in increased serial performance and achieved parallel speedups on a 24-core Intel Skylake computing platform.
JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS
(2021)
Article
Mathematics, Applied
Long Cu Ngo, Quang-Ngoc Dinh, Hyoung Gwon Choi
Summary: In this paper, a high-order reinitialization method for the level set function previously developed for structured grids is extended to unstructured grids. The proposed method shows high-order accuracy in estimating not only the signed distance function, but also geometric quantities for a smooth interface. A local correction procedure is developed for level set problems involving interfaces with kinks.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2022)
Article
Computer Science, Interdisciplinary Applications
Sara Tro, Tyco Mera Evans, Tariq D. Aslam, Eduardo Lozano, David B. Culp
Summary: This paper introduces a second-order distributed memory parallel fast sweeping method for calculating wave propagation and distance fields. Compared to the first-order method, the second-order method improves the solution, allowing for memory savings while achieving the same accuracy.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Engineering, Multidisciplinary
Jooyoung Hahn, Karol Mikula, Peter Frolkovic, Branislav Basara
Summary: A cell-centered finite volume method with the Soner boundary condition is proposed for computing the signed distance function in general 3D computational domains. The numerical method is based on the bidirectional time-relaxed eikonal equation and shows second order accuracy in L1 and L infinity-norms. The inclusion of the Soner boundary condition is necessary for numerical solutions to reach the viscosity solution of the eikonal equation in general 3D domains starting from various initial conditions.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING
(2022)
Article
Optics
Jian-Hua Qin, Ying-Bin Liu, Ting-Ting Huang, Hui-Dong Zhang
Summary: This study proposes a dynamic iris inner edge localization method based on a distance regularized level set model, which accurately positions the inner edge of the iris and significantly reduces the localization time and iteration count while ensuring positioning accuracy.
Article
Physics, Mathematical
Yong Yang, Wenrui Hao, Yong-Tao Zhang
Summary: The second-order continuous finite element method for solving the static Eikonal equation is developed using the vanishing viscosity approach with a homotopy method. It ensures convergence of the nonlinear solver for all viscosity coefficients and examples over all grids.
COMMUNICATIONS IN COMPUTATIONAL PHYSICS
(2022)
Article
Engineering, Multidisciplinary
Mehrullah Mehr, Davood Rostamy
Summary: This article presents an efficient method to solve the Eikonal equation using the differential quadrature method, aiming to achieve accuracy and performance. A novel grid points are introduced to reduce errors, and the accuracy and stability of numerical results for two and three-dimensional Eikonal equations are demonstrated. The method is shown to be capable for certain numerical examples, with evaluations on accuracy and performance.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Mechanics
Andreas Lintermann, Matthias Meinke, Wolfgang Schroeder
INTERNATIONAL JOURNAL OF COMPUTATIONAL FLUID DYNAMICS
(2020)
Article
Physics, Fluids & Plasmas
Thomas Schilden, Alexej Pogorelov, Sohel Herff, Wolfgang Schroeder
PHYSICAL REVIEW FLUIDS
(2020)
Article
Physics, Fluids & Plasmas
Marian Albers, Wolfgang Schroeder
PHYSICAL REVIEW FLUIDS
(2020)
Article
Physics, Fluids & Plasmas
Esther Maeteling, Michael Klaas, Wolfgang Schroeder
PHYSICAL REVIEW FLUIDS
(2020)
Article
Mechanics
Konstantin Froehlich, Pooria Farmand, Heinz Pitsch, Matthias Meinke, Wolfgang Schroeder
Summary: A recently developed drag correlation for ellipsoidal particles is applied in a Lagrangian point-particle model. Results show that the pitching torque due to fluid inertia dominates the torque contribution due to the fluid velocity gradient, leading to the major axis being preferentially oriented perpendicular to the settling direction.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2021)
Article
Mechanics
X. Q. Cheng, C. W. Wong, F. Hussain, W. Schroeder, Y. Zhou
Summary: An experimental study was conducted on controlling a turbulent boundary layer (TBL) on a flat plate using plasma actuators, resulting in a drag reduction of up to 26%. The study found that the drag reduction phenomenon persists downstream, with three distinct spatial regions characterized by drag increase, pronounced drag reduction, and drag recovery, all related to large-scale streamwise vortices.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Materials Science, Multidisciplinary
Ralf Berger, Markus Apel, Gottfried Laschet, Wilhelm Jessen, Wolfgang Schroeder, Jens Wipperfuerth, Johannes Austermann, Christian Hopmann
Summary: This study focuses on the equiaxed solidification process of the Al-Si-Mg alloy A356, using the phase field method to simulate 3D solidification structures at different stages and measuring permeability through additive manufacturing and fluid flow simulations. The research found that the deviation between measured permeability values and simulated results is small due to the geometric constraint effect.
Article
Automation & Control Systems
Ophelia Frotscher, Ingo Schaarschmidt, Daniel Lauwers, Raphael Paul, Matthias Meinke, Philipp Steinert, Andreas Schubert, Wolfgang Schroeder, Markus Richter
Summary: The study aims to understand the magnetic field-assisted electrochemical machining process and lay the foundation for subsequent process simulations, focusing on the influence of the Lorentz force in a NaNO3 electrolyte.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2022)
Article
Mechanics
Thede Kiwitt, Konstantin Froehlich, Matthias Meinke, Wolfgang Schroeder
Summary: This study investigates the heat transfer characteristics of a fixed, prolate ellipsoid of constant temperature immersed in uniform flow conditions through direct numerical simulations. The results show that the heat transfer is primarily influenced by the Reynolds number and the temperature ratio, while the inclination angle has a larger impact at higher aspect ratios of the particles.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2022)
Article
Physics, Fluids & Plasmas
Esther Maeteling, Wolfgang Schroeder
Summary: This paper proposes a novel spatiotemporal multivariate approach to study the interaction between near-wall turbulence and outer-layer large-scale motions in turbulent wall-bounded flows. The research findings suggest a considerable time-dependent behavior and strong correlation between inner-outer interaction and the rates of high-speed large scales.
PHYSICAL REVIEW FLUIDS
(2022)
Article
Mechanics
Esther Mateling, Marian Albers, Wolfgang Schroder
Summary: Investigation of the alteration of the near-wall flow field in a turbulent boundary layer flow subjected to spanwise travelling transversal surface waves at a friction Reynolds number Re tau asymptotic to 1525 reveals that this flow control method induces periodic large-scale bursts near the wall and reduces the energetic content of small-scale features. The occurrence of intense large-scale ejections near the wall is crucial for reducing wall-shear stress, as they balance large-scale sweeps from the outer layer, thus attenuating overall fluctuation intensity. Additionally, the periodic secondary flow field interferes with the quasi-streamwise vortices near the wall, deforming their cross-section into an elliptic shape and resulting in vortex disintegration, which, combined with the effect of large-scale ejections, leads to a decrease in wall-normal momentum exchange and the weakening of near-wall streaks.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Physics, Fluids & Plasmas
Sutharsan Satcunanathan, Matthias Meinke, Wolfgang Schroeder
Summary: This study investigates the subsonic flows around NACA 0012 aerofoils with a solid, porous, and poro-serrated trailing edge using a hybrid RANS/LES approach. It is found that the presence of porosity locally increases the turbulence intensity and alters near wall turbulence anisotropy.
Proceedings Paper
Computer Science, Artificial Intelligence
Mario Ruettgers, Moritz Waldmann, Wolfgang Schroeder, Andreas Lintermann
Summary: The presented method combines reinforcement learning algorithm with thermal lattice-Boltzmann method to control flow through a two-dimensional heated channel with a bump. The algorithm is trained to modify the bump to achieve equally important fluid mechanical properties. After multiple simulations, the algorithm accurately predicts the optimal disturbance factor of the bump and reduces the error significantly.
HIGH PERFORMANCE COMPUTING - ISC HIGH PERFORMANCE DIGITAL 2021 INTERNATIONAL WORKSHOPS
(2021)
Article
Engineering, Multidisciplinary
Gonzalo Brito Gadeschi, Thomas Schilden, Marian Albers, Julian Vorspohl, Matthias Meinke, Wolfgang Schroeder
Summary: Efficient removal of material debris by flushing is crucial for the performance and surface quality in electrical discharge machining (EDM). Particle concentration affects the properties of the particle-dielectricum suspension, influencing heat transfer and manufacturing process. Increasing particle loading has a significant impact on heat transfer and the rate of particle flushing out of the cavity.
ENGINEERING APPLICATIONS OF COMPUTATIONAL FLUID MECHANICS
(2021)
Article
Energy & Fuels
Soren Wellenberg, Markus Marnett, Benedikt Roidl, Davis Kirkendall, Frederik Thoennissen, Wolfgang Schroeder
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)