International Journal for Numerical Methods in Fluids最新文献_第9页

Computational Treatment of Three Dimensional Transient Magnetized Casson Fluid Across an Inclined Surface Subject to Heat Source/Sink and First Order Chemical Reaction Effect 热源/热源作用下三维瞬态磁化卡森流体在倾斜表面的计算处理及一级化学反应效应

IF 1.8 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2025-07-24 DOI: 10.1002/fld.70007

Hakim AL Garalleh, Haroon Ur Rasheed, Waris Khan, Emad E. Mahmoud, Afnan Al Agha

{"title":"Computational Treatment of Three Dimensional Transient Magnetized Casson Fluid Across an Inclined Surface Subject to Heat Source/Sink and First Order Chemical Reaction Effect","authors":"Hakim AL Garalleh, Haroon Ur Rasheed, Waris Khan, Emad E. Mahmoud, Afnan Al Agha","doi":"10.1002/fld.70007","DOIUrl":"https://doi.org/10.1002/fld.70007","url":null,"abstract":"<div>\u0000 \u0000 The induced convective flow of three-dimensional Casson nanofluid governed by a bi-directional stretching surface has potential practical implications in numerous engineering fields, such as heat exchangers, cooling systems for heat-generating devices, and more. This investigation aims to analytically examine the natural convection mechanism and heat transfer analysis of a Casson nanofluid inside a porous surface exposed to a uniform magnetic field. Moreover, this research explores the physical insights of thermal characteristics by incorporating the effects of chemical reactions, velocity slip, Brownian diffusion, and heat sources/sinks on the transient magnetohydrodynamic flow of the nanofluid. The proposed flow framework is described by a system of partial differential equations, which are transformed into dimensionless ordinary differential equations using appropriate variables. The closed-form solutions of a set of leading characteristic dimensionless equations are obtained analytically through the efficient homotopic analysis method. Furthermore, stability and convergence analyses of the series solutions are performed to validate the computational results explicitly. The computational findings reveal a significant decrease in flow velocity, temperature, and particle concentration profiles as the Casson fluid parameter increases. Additionally, the effects on skin friction, Nusselt number, and Sherwood number are discussed in detail. This study aims to enhance the understanding of flow dynamics and heat and mass transfer mechanisms across various applications, offering valuable insights for engineering and scientific advancements. The authors accept that all the computational outcomes in this research, both analytical and numerical, are authentic and not published elsewhere.\u0000 </div>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 12","pages":"1506-1518"},"PeriodicalIF":1.8,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145436465","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

Space-Time Modeling and Numerical Simulations of Non-Newtonian Fluids Using Internal Variables 使用内变量的非牛顿流体的时空建模和数值模拟

IF 1.8 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2025-07-14 DOI: 10.1002/fld.5406

Philipp Junker, Thomas Wick

{"title":"Space-Time Modeling and Numerical Simulations of Non-Newtonian Fluids Using Internal Variables","authors":"Philipp Junker, Thomas Wick","doi":"10.1002/fld.5406","DOIUrl":"https://doi.org/10.1002/fld.5406","url":null,"abstract":"The modeling of fluids is an important field for mechanics of materials. In this work, we demonstrate that Hamilton's principle, which is well-known for the modeling of solids, can also be formulated to derive the Navier–Stokes equations, which paves the way for easy inclusion of complex material constraints. Furthermore, we expand Hamilton's principle to enable the introduction of “internal variables”, which describe the space- and time-dependent evolution of the material properties. Hereby, a novel strategy for the modeling of non-Newtonian fluids is given. Eventually, Hamilton's principle inherently enables a space-time formulation with the automatic derivation of the correct formal functional setting, which covers different scales of viscosity through the internal variable. The resulting system is a space-time multiscale model for fluid flow, which is based on an additional partial differential equation. The model constitutes thus a much more adaptive description of the complex processes in non-Newtonian fluid flow as possible for classical models based on algebraic constitutive laws. This also includes a spatially and temporally local evolution of the effective viscosity, depending on the local flow conditions rather than material parameters and resulting in both shear-thinning and shear-thickening behavior. Numerical examples substantiate our proposed setting by some studies from Newtonian flow to non-Newtonian regimes with fading or increasing viscosity.","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 12","pages":"1457-1481"},"PeriodicalIF":1.8,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/fld.5406","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145435994","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

Unified Interpolated-Based Scheme for Curved Boundary Treatment of the Discrete Unified Gas Kinetic Scheme 离散统一气体动力学格式曲线边界处理的统一插值方法

IF 1.8 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2025-07-14 DOI: 10.1002/fld.70006

Wenqiang Guo

引用次数: 0

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":"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.","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":"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.","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 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.\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":"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.","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":"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-TiO2 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 k-ω 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 TiO2-CNT/water HyNf with ϕ = 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.","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