International Journal for Numerical Methods in Fluids最新文献

Accelerating Vortex Particle Methods by Downsampling the Vorticity Field Representation 下采样涡旋场表示的加速涡旋粒子方法

IF 1.8 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2025-07-01 DOI: 10.1002/fld.70002

Jakub Siemaszko, Rention Pasolari, Alexander van Zuijlen

{"title":"Accelerating Vortex Particle Methods by Downsampling the Vorticity Field Representation","authors":"Jakub Siemaszko, Rention Pasolari, Alexander van Zuijlen","doi":"10.1002/fld.70002","DOIUrl":"https://doi.org/10.1002/fld.70002","url":null,"abstract":"<p>Computational efficiency of vortex particle methods (VPMs) is hindered by the particle count increasing in simulation time. To reduce the number of computational elements, two algorithms are presented that downsample the discretized vorticity field representation in two-dimensional variable-core-size VPMs. The two methods are based on existing schemes of particle merging and regridding, and are adapted to follow a compression parameter set a priori. The effectiveness of the schemes is demonstrated on two benchmark cases of external flow: A stationary Lamb-Oseen vortex and an advecting vortex dipole. In both cases, compression is associated with a drastic reduction in particle count and computation time at a cost of diffusive errors in the vorticity field. Crucially, for gentle compression steps applied at appropriate intervals, the immediate errors in the vorticity field are comparable to reference cases despite great improvements in computational time. To examine the long-term impact of compression on accuracy and performance, it is recommended that repeated compressive steps be tested on more complex cases of bluff-body wakes, with a focus on the impact of downsampling on surface forces.</p>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 11","pages":"1410-1425"},"PeriodicalIF":1.8,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/fld.70002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145242851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Discretization-Corrected Particle Strength Method for the Barotropic Vorticity Equations 正压涡度方程的离散化修正粒子强度法

IF 1.8 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2025-07-01 DOI: 10.1002/fld.70003

G. C. Bourantas, A. Sakellarios, N. Malamos, V. C. Loukopoulos, V. N. Burganos, K. Miller, A. Langousis, D. I. Fotiadis, A. A. Dimas, V. M. Calo

{"title":"The Discretization-Corrected Particle Strength Method for the Barotropic Vorticity Equations","authors":"G. C. Bourantas, A. Sakellarios, N. Malamos, V. C. Loukopoulos, V. N. Burganos, K. Miller, A. Langousis, D. I. Fotiadis, A. A. Dimas, V. M. Calo","doi":"10.1002/fld.70003","DOIUrl":"https://doi.org/10.1002/fld.70003","url":null,"abstract":"<p>We present a novel meshless Lagrangian method for numerically solving the barotropic vorticity equation on a rotating sphere, an essential model in geophysical fluid dynamics. Our approach combines a particle-based discretization with a Discretization Corrected Particle Strength Exchange (DCPSE) operator, offering a consistent and accurate approximation of differential operators on unstructured node distributions. The method is implemented in a fully Lagrangian framework, inherently conserving circulation and enabling straightforward adaptation to complex geometries. We validate the proposed scheme against standard test cases for global circulation and Rossby-Haurwitz waves. The results demonstrate excellent agreement with reference solutions obtained from high-resolution spectral and finite difference models. In particular, our method captures the essential dynamics of the vorticity field with high fidelity and low numerical diffusion, while exhibiting convergence and stability properties suitable for long-term integrations. This study highlights the potential of meshless Lagrangian techniques in large-scale geophysical simulations. These techniques provide an alternative to traditional grid-based approaches and facilitate the natural handling of adaptive and irregular node distributions.</p>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 11","pages":"1426-1440"},"PeriodicalIF":1.8,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/fld.70003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145242990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermally Radiative Flow of Cattaneo–Christov Heat Flux in MHD Darcy–Forchheimer Micropolar Nanofluid With Activation Energy 具有活化能的MHD Darcy-Forchheimer微极纳米流体中Cattaneo-Christov热流的热辐射流

IF 1.8 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2025-07-01 DOI: 10.1002/fld.70004

Kakanuti Malleswari, Jintu Mani Nath, Mulinti Vinodkumar Reddy, Kakarla Ramakrishna Reddy, Bamdeb Dey

{"title":"Thermally Radiative Flow of Cattaneo–Christov Heat Flux in MHD Darcy–Forchheimer Micropolar Nanofluid With Activation Energy","authors":"Kakanuti Malleswari, Jintu Mani Nath, Mulinti Vinodkumar Reddy, Kakarla Ramakrishna Reddy, Bamdeb Dey","doi":"10.1002/fld.70004","DOIUrl":"https://doi.org/10.1002/fld.70004","url":null,"abstract":"<div>\u0000 \u0000 <p>The present inquiry examines the necessity for enhanced thermal transfer approaches across multiple industrial domains, such as energy generation and processing of materials, through an investigation of the intricate dynamics of micropolar nanofluids. The main objective is to numerically simulate the Cattaneo–Christov heat flux in magnetohydrodynamics (MHD) to investigate the radiative behavior of Darcy–Forchheimer micropolar nanofluids, including the effects of activation energy. The study presumes steady-state conditions and employs particular constitutive equations to characterize the behavior of the nanofluid. The governing equations, which incorporate binary chemical interactions, radiation, and a thermal source, are reformulated with similarity variables into a system of nonlinear ordinary differential equations (ODEs). The BVP4C MATLAB software is utilized for obtaining numerical solutions. The study indicates that an increase in thermophoresis, thermal source, radiation, and Brownian motion factors improves thermal distributions in micropolar nanofluid flow. Moreover, increased radiation parameters result in a rise in the thermal transmission rate, while enhancing activation energy factors leads to a decrease. The findings are essential for enhancing temperature control in systems and for the development of efficient thermal appliances.</p>\u0000 </div>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 11","pages":"1441-1455"},"PeriodicalIF":1.8,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145242989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Control Volume Free Element Method for Solving Turbulent Forced and Natural Convection Problems 求解湍流强迫和自然对流问题的控制体积自由元法

IF 1.8 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2025-06-30 DOI: 10.1002/fld.5403

Jin-Xing Ding, Hua-Yu Liu, Xiao-Wei Gao

引用次数: 0

A Filter-Matrix Lattice-Boltzmann Methodology for Convective Melting and Solidification 对流熔化和凝固的滤波-矩阵晶格-玻尔兹曼方法学

IF 1.8 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2025-06-26 DOI: 10.1002/fld.70001

Celeke Bus, Thorben Besseling, Martin Rohde

引用次数: 0

Error Analysis of a Pressure-Correction Method With Explicit Time-Stepping 显式时间步进压力校正方法的误差分析

IF 1.8 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2025-06-26 DOI: 10.1002/fld.70000

Utku Kaya, Thomas Richter

{"title":"Error Analysis of a Pressure-Correction Method With Explicit Time-Stepping","authors":"Utku Kaya, Thomas Richter","doi":"10.1002/fld.70000","DOIUrl":"https://doi.org/10.1002/fld.70000","url":null,"abstract":"<p>The pressure-correction method is a well-established approach for simulating unsteady, incompressible fluids. It is well-known that implicit discretization of the time derivative in the momentum equation, for example, using a backward differentiation formula with explicit handling of the nonlinear term, results in a conditionally stable method. In certain scenarios, employing explicit time integration in the momentum equation can be advantageous, as it avoids the need to solve for a system matrix involving each differential operator. Additionally, we demonstrate that the fully discrete method can be written in the form of simple matrix-vector multiplications, allowing for efficient implementation on modern and highly parallel acceleration hardware. Despite being a common practice in various commercial codes, there is currently no literature available on error analysis for this scenario. In this work, we conduct a theoretical analysis of both implicit and two explicit variants of the pressure-correction method in a fully discrete setting. We demonstrate the extent to which the presented implicit and explicit methods exhibit conditional stability. Furthermore, we establish a Courant–Friedrichs–Lewy (CFL) type condition for the explicit scheme and show that the explicit variant demonstrates the same asymptotic behavior as the implicit variant when the CFL condition is satisfied.</p>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 10","pages":"1363-1378"},"PeriodicalIF":1.8,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/fld.70000","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144927818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermal–Hydraulic Performance of Nanofluids in Turbulent Separated Flow Induced by Double Forward Facing Step With Converging/Diverging Wall 纳米流体在汇聚/发散壁面双前台阶诱导的湍流分离流中的热工性能

IF 1.8 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2025-06-14 DOI: 10.1002/fld.5409

Mahmoud Jourabian, Mehrdad Raeesi

{"title":"Thermal–Hydraulic Performance of Nanofluids in Turbulent Separated Flow Induced by Double Forward Facing Step With Converging/Diverging Wall","authors":"Mahmoud Jourabian, Mehrdad Raeesi","doi":"10.1002/fld.5409","DOIUrl":"https://doi.org/10.1002/fld.5409","url":null,"abstract":"<p>Researchers have proposed multifarious passive methods for heat transfer augmentation over geometries with separation and reattachment. In this study, the turbulent forced convection flow of water-based CNT-TiO<sub>2</sub> hybrid nanofluid, ND-Ni hybrid nanofluid, and mono Ni nanofluid (with temperature-dependent properties) in a double forward-facing step channel with a converging/diverging bottom adiabatic wall is evaluated. The single-phase shear stress transport <i>k</i>-<i>ω</i> model is applied to solve the governing equations. Results indicate that the highest thermo-hydraulic performance (the value of figure-of-merit is equal to 1.1) can be achieved using TiO<sub>2</sub>-CNT/water HyNf with <i>ϕ</i> = 0.002. Generally, as the velocity of the incoming stream is reduced, the thermal efficacy of HyNf improves. When the water-based NFs are not an effective heat transfer fluid (inducing a performance evaluation criterion lower than unity), the diverging channel (weakening of the contact between surfaces with constant heat flux and working fluid) can be employed instead of the DFFS channel while the Reynolds number of the incoming flow reduces as well. It is found that the thermal efficacy of water-based NFs in complex separated flows depends strongly not only on the deflection angle of the bottom adiabatic wall but also on the velocity of the incoming flow.</p>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 10","pages":"1343-1362"},"PeriodicalIF":1.8,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/fld.5409","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144927703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Three-Directional Orthogonality Preserving Method for Hyperbolic Grid Generation 双曲网格生成的三向正交保持方法

IF 1.8 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2025-06-09 DOI: 10.1002/fld.5407

Siyuan Pi, Hongyuan Lin, Shuyao Hu, Chongwen Jiang, Chun-Hian Lee

{"title":"Three-Directional Orthogonality Preserving Method for Hyperbolic Grid Generation","authors":"Siyuan Pi, Hongyuan Lin, Shuyao Hu, Chongwen Jiang, Chun-Hian Lee","doi":"10.1002/fld.5407","DOIUrl":"https://doi.org/10.1002/fld.5407","url":null,"abstract":"<div>\u0000 \u0000 <p>The hyperbolic grid generation method is widely used for generating computational grids. Because of conflicts arising from various grid constraints, the traditional hyperbolic grid generation method faces challenges in guaranteeing the fulfillment of all orthogonal constraints among three directions during the grid generation. A new three-directional orthogonality preserving method (TDOP) is introduced in the present work to enhance the orthogonality of the computational grid during the grid generation process. Unlike the traditional grid generation method, TDOP takes all three orthogonal constraints into consideration, establishes a function to quantify the overall grid orthogonality, and subsequently derives new governing equations for grid generation by solving a constrained optimization problem. Compared with the traditional method, TDOP exhibits enhanced control over the orthogonality among three directions, thereby enabling the generation of a computational grid with better orthogonality. Three application cases are employed to demonstrate the effectiveness and superiority of TDOP in hyperbolic grid generation. Results indicate that, compared with the traditional method, TDOP can effectively prevent the emergence of highly skewed grids and enables enhanced optimization of orthogonality in the advancing front layer. Consequently, TDOP can generate a computational grid with better orthogonality and higher quality than the traditional method.</p>\u0000 </div>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 10","pages":"1321-1342"},"PeriodicalIF":1.8,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144927610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Higher Order Method Based on the Combination of Local Discontinuous Galerkin and Spectral Deferred Correction Method for the Rotating Navier–Stokes Equations 旋转Navier-Stokes方程的基于局部不连续Galerkin和谱延迟校正相结合的高阶方法

IF 1.8 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2025-06-06 DOI: 10.1002/fld.5408

Xuewei Zhang, Demin Liu

{"title":"Higher Order Method Based on the Combination of Local Discontinuous Galerkin and Spectral Deferred Correction Method for the Rotating Navier–Stokes Equations","authors":"Xuewei Zhang, Demin Liu","doi":"10.1002/fld.5408","DOIUrl":"https://doi.org/10.1002/fld.5408","url":null,"abstract":"<div>\u0000 \u0000 <p>In this article, the spatial local discontinuous Galerkin (LDG) method and the temporal spectral deferred correction (SDC) method are combined to construct the higher-order approximating method for the unsteady rotating Navier–Stokes equations on the triangular mesh. First, the artificially compressible method is used to circumvent the incompressibility constraint, and the rotating Navier–Stokes equations are transformed into the artificially compressible rotating Navier–Stokes equations. Then, based on equal LDG interpolation and repeated temporal SDC, the higher-order fully discrete method is presented. Theoretically, the stability analysis of the second-order fully discrete method is provided, and it is shown that the time step <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>τ</mi>\u0000 </mrow>\u0000 <annotation>$$ tau $$</annotation>\u0000 </semantics></math> is stable within the upper bound constraints. Numerical examples are presented to demonstrate the effectiveness of the proposed method.</p>\u0000 </div>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 9","pages":"1303-1318"},"PeriodicalIF":1.8,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144767639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An Extended HLLD Riemann Solver for the Numerical Simulation of Magneto-Hydrodynamics 磁流体力学数值模拟的扩展hld Riemann求解器

IF 1.8 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2025-06-06 DOI: 10.1002/fld.5405

Xiaocheng Guo, Xinyue Xi, Chi Wang

{"title":"An Extended HLLD Riemann Solver for the Numerical Simulation of Magneto-Hydrodynamics","authors":"Xiaocheng Guo, Xinyue Xi, Chi Wang","doi":"10.1002/fld.5405","DOIUrl":"https://doi.org/10.1002/fld.5405","url":null,"abstract":"<div>\u0000 \u0000 <p>By revisiting the derivation of multi-state HLL approximate Riemann solver for the ideal magneto-hydrodynamics, an extended HLLD Riemann solver is constructed based on the assumption that the normal velocity is constant over the Riemann fan, which is bounded by two fast waves, and separated by two compound waves and a middle contact wave. Compared with the HLLD solver, the slow waves are allowed to persist inside the Riemann fan, so that the two Alfvén waves are replaced by the two compound waves that are the merging product of the Alfvén and slow waves. Conseq uently, the corresponding wave speeds are chosen to be an interpolation between the Alfvén and slow waves for simplicity. The numerical tests showed that the extended HLLD solver (called HLLD-P) has better performance for the capture of slow waves than the HLLD solver, and exhibits overall better accuracy in some situations where the slow waves exist. However, the new solver does not capture the Alfvén wave as well as the HLLD solver once the estimated speeds of compound waves deviate from the Alfvén wave speeds. Overall, the HLLD-P solver is fully compatible with the HLLD solver as long as the compound waves degenerate to the Alfvén waves inside the Riemann fan. It is indicated that the HLLD-P solver can be used for the various applications of MHD simulation, especially for those cases where the slow waves are expected to be generated.</p>\u0000 </div>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 9","pages":"1289-1302"},"PeriodicalIF":1.8,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144767609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0