Journal of Computational Physics最新文献

{"title":"A cell-centered AMR-ALE framework for 3D multi-material hydrodynamics. Part I: Lagrangian and indirect Euler AMR algorithms","authors":"A. Colaïtis ,&nbsp;S. Guisset ,&nbsp;J. Breil","doi":"10.1016/j.jcp.2026.114701","DOIUrl":"10.1016/j.jcp.2026.114701","url":null,"abstract":"<div><div>Many applications of physics and engineering involve wide ranges of time and spatial scales. The numerical simulation of localized small scales such as shock waves and material interfaces requires a large number of computational cells in these regions. For these applications, Lagrangian and Arbitrary-Lagrangian-Eulerian (ALE) related methods are engaging since the moving mesh feature naturally brings mesh cells on shock discontinuities and material interfaces are carefully captured. In addition, Adaptive-Mesh-Refinement (AMR) strategies aim to optimize computational resources by concentrating finer mesh cells only in areas of interest while using coarser cells elsewhere. A key but challenging AMR requirement consists in efficiently distributing the computational effort to achieve high accuracy without the prohibitive computational costs associated with uniformly fine grids. In this document, the coupling of the <em>p4est</em> AMR library with a cell-centered Lagrangian scheme is presented with the goal to perform reliable 3D Lagrangian-AMR and indirect Euler-AMR multi-material simulations. In particular, it is shown that starting from a 3D indirect ALE code, the memory management and load balancing requirements can be delegated to an external library (here the <em>p4est</em> library) to unlock ALE-AMR capabilities. First, we present a strategy to transcribe the octant-based connectivity of the 3D AMR framework with that of an unstructured mesh of polygonal cells used in Lagrangian hydrodynamics. Then, we show how refinement and coarsening operations must be adapted to the particular Lagrangian framework to ensure the conservation of volume during those steps. Finally, several numerical test cases are presented that demonstrate the capabilities of the Lagrangian-AMR and indirect Euler-AMR algorithms.</div></div>","PeriodicalId":352,"journal":{"name":"Journal of Computational Physics","volume":"552 ","pages":"Article 114701"},"PeriodicalIF":3.8,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146075600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An exact mass-conserving arbitrary Lagrangian-Eulerian framework for viscoelastic multiphase fluid flows","authors":"Cagatay Guventurk,&nbsp;Mehmet Sahin","doi":"10.1016/j.jcp.2026.114695","DOIUrl":"10.1016/j.jcp.2026.114695","url":null,"abstract":"<div><div>An arbitrary Lagrangian Eulerian (ALE) framework presented in <em>A mass conserving arbitrary Lagrangian-Eulerian formulation for three-dimensional multiphase fluid flows</em>, International Journal for Numerical Methods in Fluids 94 (4), 346–376 has been extended to solve incompressible multiphase viscoelastic flow problems in two- and three-dimensions. The incompressible, isothermal linear momentum balance equations, coupled with the viscoelastic constitutive models Oldroyd-B and FENE-CR, are discretized using a div-stable, side-centered finite volume approach in which the velocity components are defined at the mid-points of element faces, the displacement vector is defined at the vertices, and the pressure and modified conformation tensor are defined at the element centroids. At the interface, the surface tension force is treated as a force tangential to the interface, and its normal vector is evaluated by using the mean weighted by sine and edge length reciprocals (MWSELR) approach. In order to ensure mass conservation of both species at machine precision, special attention is given to enforcing the kinematic boundary condition at the interface in the normal direction, while obeying the discrete geometric conservation law (DGCL). The numerical approach allows discontinuities in material properties, including density and viscosity, as well as in the pressure and modified conformation tensor across the interface. The discrete algebraic equations arising from the incompressible linear momentum balance equations are solved monolithically using a block preconditioner based on the BoomerAMG parallel algebraic multigrid solver from the HYPRE library, interfaced through PETSc. To validate the numerical algorithm, the benchmark problem of a single Newtonian or viscoelastic bubble (modeled using Oldroyd-B and FENE-CR) rising through a quiescent Newtonian or viscoelastic fluid is examined in both two- and three-dimensions. The numerical simulations exhibit excellent agreement with previous results in the literature and show strong consistency with mesh refinement. Positive and negative transient wakes are observed behind the bubble, demonstrating that the formation of a transient negative wake does not require a viscoelastic fluid model with shear-thinning behavior. The numerical approach successfully preserves the volume of the bubble to nearly machine precision and accurately captures discontinuities in the pressure and modified conformation tensor across the interface, where there are jumps in density and viscosity.</div></div>","PeriodicalId":352,"journal":{"name":"Journal of Computational Physics","volume":"552 ","pages":"Article 114695"},"PeriodicalIF":3.8,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146025860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An online interactive physics-informed diffusion-adversarial network for solving mean field games","authors":"Longqiang Xu ,&nbsp;Weishi Yin ,&nbsp;Pinchao Meng ,&nbsp;Zhengxuan Shen ,&nbsp;Hongyu Liu","doi":"10.1016/j.jcp.2026.114700","DOIUrl":"10.1016/j.jcp.2026.114700","url":null,"abstract":"<div><div>High-dimensional, complex, and dynamic environments pose significant challenges in solving mean field games (MFGs). To address these challenges, we propose an online interactive physics-informed diffusion-adversarial network (IPIDAN), which offers enhanced interpretability and flexibility by leveraging a novel agent strategy generator based on diffusion models. This generator utilizes a noise process to improve its ability to escape local optima, while a stepwise optimization process during the denoising phase generates refined agent strategies, thereby enhancing the quality and diversity of the generated results. The discriminator perceives the distribution and strategies of agents in MFGs by extracting the physical information exchange from agent interactions. By using variational techniques, the typical MFG problem is transformed into a static optimization problem, which is then efficiently approximated using a generative adversarial framework through adversarial training. IPIDAN, with its diffusion generation model architecture, provides the network with greater tunability and significantly enhances its ability to model randomness in high-dimensional strategy spaces. Furthermore, by establishing a connection between the diffusion process and the agents’ motion dynamics, the network achieves improved interpretability and robustness. Numerical experiments and comparisons with experimental results validate the effectiveness of the novel agent strategy generator based on diffusion models, particularly demonstrating its superior performance through quadrotor obstacle avoidance experiments conducted in various complex scenarios.</div></div>","PeriodicalId":352,"journal":{"name":"Journal of Computational Physics","volume":"552 ","pages":"Article 114700"},"PeriodicalIF":3.8,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146025849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A cell-centered AMR-ALE framework for 3D multi-material hydrodynamics. Part II: linesweep ALE rezoning for nonconformal block-structured AMR meshes","authors":"Arnaud Colaïtis ,&nbsp;Sébastien Guisset ,&nbsp;Jérôme Breil","doi":"10.1016/j.jcp.2026.114702","DOIUrl":"10.1016/j.jcp.2026.114702","url":null,"abstract":"<div><div>The simulation of flows presenting contact discontinuities, vorticity, and large variations in spatial scales can be performed in a framework coupling Arbitrary Lagrangian Eulerian (ALE) algorithms and Adaptive Mesh Refinement (AMR). This coupling requires adaptation of ALE rezoning techniques to meshes containing nonconformal nodes arising from both the AMR topology and the junction of mesh blocks. In this paper, we present an ALE rezoning strategy that is compatible with such meshes, and that can also act as a disentangling algorithm. Emphasis is put on an algorithm that respects intrinsic Lagrangian mesh properties in order to preserve accuracy around discontinuities. To that end, we adapt the weighted linesweep algorithm to nonconformal block-structured AMR meshes. Then, we present control parameters introduced in the method for it to be applicable in practical situations. Notably, the method is coupled to a specific metric optimization in order to palliate some shortcomings of the linesweep method. Finally, numerical test cases are presented that feature the capabilities of the ALE-AMR algorithm for flows that present discontinuities, vorticity, and a variety of scales. Notably, we show that our ALE-AMR algorithm gives results at least similar to Euler-AMR, but provides better accuracy in cases where discontinuities are involved, thanks to a method that respects the Lagrangian features of the mesh. Additionally, it enables Euler-AMR-like computations on domains with temporally varying domain boundaries.</div></div>","PeriodicalId":352,"journal":{"name":"Journal of Computational Physics","volume":"552 ","pages":"Article 114702"},"PeriodicalIF":3.8,"publicationDate":"2026-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146025850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Curvilinear Lagrangian discontinuous Galerkin method for resistive magneto-hydrodynamics","authors":"Ruoyu Han ,&nbsp;Zijin Zhu ,&nbsp;Yibing Chen ,&nbsp;Guoxi Ni","doi":"10.1016/j.jcp.2026.114698","DOIUrl":"10.1016/j.jcp.2026.114698","url":null,"abstract":"<div><div>In this paper, we present a cell-centered Lagrangian discontinuous Galerkin (DG) method for solving resistive magneto-hydrodynamics (MHD). The equations are solved using an implicit-explicit (IMEX) method. The right-hand side of the equations is classified as a hydrodynamic contribution, which is solved explicitly, and a magnetodynamic contribution which is solved implicitly. The conservative variables are discretized using Taylor basis functions within the reference element, and for magnetic field discretization, we employ a locally divergence-free basis, and it is transformed to the reference element using the Piola transformation. Nodal velocities are determined through an approximate Riemann solver. Curvilinear mesh is achieved through basis function deformation in physical space. Numerical experiments demonstrate the accuracy and robustness of the method.</div></div>","PeriodicalId":352,"journal":{"name":"Journal of Computational Physics","volume":"551 ","pages":"Article 114698"},"PeriodicalIF":3.8,"publicationDate":"2026-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SFVnet: Finite-volume informed U-net for compressible flow prediction with sparse data under ill-conditions","authors":"Tong Zhu ,&nbsp;Bingqian Si ,&nbsp;Lin Fu ,&nbsp;Yanglong Lu","doi":"10.1016/j.jcp.2026.114696","DOIUrl":"10.1016/j.jcp.2026.114696","url":null,"abstract":"<div><div>Physics-informed neural network (PINN) is a promising methodology in scientific computing. However, predicting compressible flows poses a challenge for PINNs, since they struggle to accurately capture discontinuities arising in flow evolutions. In this work, a novel physics-informed deep learning framework, called sparse finite-volume informed U-net (SFVnet), is developed to predict compressible flow fields with sparse data under ill-conditions. The major contributions are as follows: (1) a new physical loss function is designed by incorporating finite volume discretized residuals and fusing predictions from multiple points within each cell, effectively improving the discontinuity-capturing ability compared to original PINN; (2) the model leverages interior sparse samples to reconstruct the full flow field without the input of initial/boundary conditions, which is particularly challenging for traditional FVM; (3) the trained model can extrapolate basic flow patterns beyond the training time window, which original PINNs fail to achieve. Furthermore, the proposed framework is distinguished by reconstructing region-of-interest flow fields by sampling data only within this region. A series of one-dimensional (1D) and two-dimensional (2D) benchmark cases, including the 1D Sod’s tube, 1D Lax’s tube, 2D Riemann problems, and double Mach reflection problem, demonstrate the prediction accuracy and robustness of the framework. Notably, this is the first physics-informed deep learning framework successfully applied to the double Mach reflection simulation with Mach number of 10. These results also indicate the potential of present framework for flow field reconstruction, data compression, and restoration.</div></div>","PeriodicalId":352,"journal":{"name":"Journal of Computational Physics","volume":"552 ","pages":"Article 114696"},"PeriodicalIF":3.8,"publicationDate":"2026-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146001718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A modified Crank-Nicolson scheme for the Vlasov-Poisson system with a strong external magnetic field","authors":"Francis Filbet ,&nbsp;L. Miguel Rodrigues ,&nbsp;Kim Han Trinh","doi":"10.1016/j.jcp.2026.114693","DOIUrl":"10.1016/j.jcp.2026.114693","url":null,"abstract":"<div><div>We propose and study a Particle-In-Cell (PIC) method utilizing Crank-Nicolson time discretization for the Vlasov-Poisson system with a strong, inhomogeneous external magnetic field with fixed direction. Our focus is on particle dynamics in the plane orthogonal to the magnetic field. In this regime, traditional explicit schemes are constrained by stability conditions linked to the small Larmor radius and plasma frequency [1]. To avoid this limitation, our approach is based on numerical schemes [2, 3, 4], providing a consistent PIC discretization of the guiding-center system taking into account variations of the magnetic field. We carry out some theoretical proofs and perform several numerical experiments to validate the method demonstrating its robustness and accuracy.</div></div>","PeriodicalId":352,"journal":{"name":"Journal of Computational Physics","volume":"552 ","pages":"Article 114693"},"PeriodicalIF":3.8,"publicationDate":"2026-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146025847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Linear high order finite difference methods with essentially non-oscillatory limiters for hyperbolic conservation laws","authors":"Zhengfu Xu","doi":"10.1016/j.jcp.2026.114686","DOIUrl":"10.1016/j.jcp.2026.114686","url":null,"abstract":"<div><div>For high order finite difference and finite volume methods solving hyperbolic conservation laws, the major challenge is to achieve nonlinear stability in the presence of discontinuous solutions. Total variation diminishing or total variation bounded flux limiters are normally set up to achieve the nonlinear stability. High order essentially non-oscillatory methods (ENO or weighted ENO) were designed to avoid constructing high order polynomials across discontinuities to ensure nonlinear stability. However, adaptively reconstructing high order polynomials and doing so in the characteristic space often contributes significantly to the overall computational cost.</div><div>Alternatives were proposed as hybrid approaches: simply put, applying limiters in the discontinuous regions of the solution while using linear high order methods in the smooth regions. The key to the success of the hybrid approach lies in the differentiation between smooth and nonsmooth regions, which is highly nontrivial given discrete data sets. In this paper, an irregularity detecting mechanism is provided along the discrete profile of the solution to determine when the nonlinear ENO or WENO methods are needed. The irregularity detector does not depend on manually adjusted parameters when problems change. Such an irregularity detector is easy to implement in the dimensional splitting setting of the finite difference methods. The numerical evidences demonstrate the performance of the newly defined irregularity detector. When applied to high order finite difference methods, the numerical results are accurate and non-oscillatory with improved efficiency.</div></div>","PeriodicalId":352,"journal":{"name":"Journal of Computational Physics","volume":"551 ","pages":"Article 114686"},"PeriodicalIF":3.8,"publicationDate":"2026-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-order nonuniform time-stepping and MBP-preserving linear schemes for the time-fractional Allen–Cahn equation","authors":"Bingyin Zhang ,&nbsp;Hong Wang ,&nbsp;Hongfei Fu","doi":"10.1016/j.jcp.2026.114694","DOIUrl":"10.1016/j.jcp.2026.114694","url":null,"abstract":"<div><div>In this paper, we present a class of nonuniform time-stepping, high-order linear stabilized schemes that can preserve both the discrete energy stability and maximum-bound principle (MBP) for the time-fractional Allen–Cahn equation. To this end, we develop a new prediction strategy to obtain a second-order and MBP-preserving predicted solution, which is then used to handle the nonlinear potential explicitly. Additionally, we introduce an essential nonnegative auxiliary functional that enables the design of an appropriate stabilization term to dominate the predicted nonlinear potential, and thus to preserve the discrete MBP. Combining the newly developed prediction strategy and auxiliary functional, we propose two unconditionally energy-stable linear stabilized schemes, <em>L</em>1 and <em>L</em>2-1_<em>σ</em> schemes. We show that the <em>L</em>1 scheme unconditionally preserves the discrete MBP, whereas the <em>L</em>2-1_<em>σ</em> scheme requires a mild time-step restriction. Furthermore, we develop an improved <em>L</em>2-1_<em>σ</em> scheme with enhanced MBP preservation for large time steps, achieved through a novel unbalanced stabilization term that leverages the boundedness and monotonicity of the auxiliary functional. Representative numerical examples validate the accuracy, effectiveness, and physics-preserving of the proposed methods.</div></div>","PeriodicalId":352,"journal":{"name":"Journal of Computational Physics","volume":"551 ","pages":"Article 114694"},"PeriodicalIF":3.8,"publicationDate":"2026-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A high-order, conservative and positivity-preserving intersection-based remapping method between meshes with isoparametric curvilinear cells","authors":"Nuo Lei ,&nbsp;Juan Cheng ,&nbsp;Chi-Wang Shu","doi":"10.1016/j.jcp.2026.114669","DOIUrl":"10.1016/j.jcp.2026.114669","url":null,"abstract":"<div><div>This paper presents a novel two-dimensional intersection-based remapping method for isoparametric curvilinear meshes within the indirect arbitrary Lagrangian-Eulerian (ALE) framework, addressing the challenges of transferring physical quantities between high-order curved-edge meshes. Our method leverages the Weiler-Atherton clipping algorithm to compute intersections between curved-edge quadrangles, enabling robust handling of arbitrary order isoparametric curves. By integrating multi-resolution weighted essentially non-oscillatory (WENO) reconstruction, we achieve high-order accuracy while suppressing numerical oscillations near discontinuities. A positivity-preserving limiter is further applied to ensure physical quantities such as density remain non-negative without compromising conservation or accuracy. Notably, the computational cost of handling higher-order curved meshes, such as cubic or even higher-degree parametric curves, does not significantly increase compared to second-order curved meshes. This ensures that our method remains efficient and scalable, making it applicable to arbitrary two-dimensional high-order isoparametric curvilinear cells without compromising performance. Numerical experiments demonstrate that the proposed method achieves high-order accuracy, strict conservation (with errors approaching machine precision), essential non-oscillation and positivity-preserving. The proposed approach is currently restricted to two-dimensional meshes, and an extension to fully three-dimensional curved polyhedral mesh is beyond the scope of the present work.</div></div>","PeriodicalId":352,"journal":{"name":"Journal of Computational Physics","volume":"551 ","pages":"Article 114669"},"PeriodicalIF":3.8,"publicationDate":"2026-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}