International Journal for Numerical Methods in Fluids最新文献

{"title":"An Improved Single-Layer Smoothed Particle Hydrodynamics Model for Water–Soil Two-Phase Flow","authors":"Zi-Yang Zhan,&nbsp;Zi-Xin Zhou,&nbsp;Zhen Chen","doi":"10.1002/fld.5371","DOIUrl":"https://doi.org/10.1002/fld.5371","url":null,"abstract":"<div>\u0000 \u0000 <p>In coastal and offshore engineering, the intense water–soil motion poses significant challenges to the safety of buildings and structures. The smoothed particle hydrodynamics (SPH) method, as a mesh-free Lagrangian solver, has considerable advantages in the numerical resolution of such problems. SPH models for the water–soil two-phase flow can be categorized into the multilayer type and the single-layer type. Although the single-layer model envisions a simpler algorithm and higher computational efficiency, its accuracy, stability, and recovery of interfacial details are far from satisfactory. In the present work, an improved single-layer model is established to alleviate these limitations. First, the soakage function, which takes effect near the phase interface, is introduced to characterize the two-phase coupling status. Additionally, the stress diffusion term and a modified density diffusion term applicable in density discontinuity scenario are introduced to ease the numerical oscillation. Finally, to remove the unphysical voids in the interfacial region, the particle shifting technique with special treatment tailored for free-surface particles is implemented. Validations of the proposed model are carried out by a number of numerical tests, including the erodible dam-break problem, the wall-jet scouring, the flushing case, and the water jet excavation. Appealing agreements with either experimental data or published numerical results have been achieved, which verifies the accuracy, stability, and robustness of the proposed model for water–soil two-phase flows.</p>\u0000 </div>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 4","pages":"546-564"},"PeriodicalIF":1.7,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143533372","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}

{"title":"A Non-Dissipative, Energy-Conserving, Arbitrary High-Order Numerical Method and Its Efficient Implementation for Incompressible Flow Simulation in Complex Geometries","authors":"Sreevatsa Anantharamu,&nbsp;Krishnan Mahesh","doi":"10.1002/fld.5369","DOIUrl":"https://doi.org/10.1002/fld.5369","url":null,"abstract":"<p>In the inviscid limit, the energy of a velocity field satisfying the incompressible Navier–Stokes equations is conserved. Non-dissipative numerical methods that discretely mimic this energy conservation feature have been demonstrated in the literature to be extremely valuable for robust and accurate large-eddy simulations of high Reynolds number incompressible turbulent flows. For complex geometries, such numerical methods have been traditionally developed using the finite volume framework and they have been at best second-order accurate. This paper proposes a non-dissipative and energy-conserving numerical method that is arbitrary high-order accurate for triangle/tetrahedral meshes along with its efficient implementation. The proposed method is a Hybridizable Discontinuous Galerkin (HDG) method. The crucial ingredients of the numerical method that lead to the discretely non-dissipative and energy-conserving features are: (i) The tangential velocity on the interior faces, just for the convective term, is set using the non-dissipative central scheme and the normal velocity is enforced to be continuous, that is, <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>H</mi>\u0000 </mrow>\u0000 <annotation>$$ H $$</annotation>\u0000 </semantics></math>(div)-conforming. (ii) An exactly (pointwise) divergence-free basis is used in each element of the mesh for the stability of the convective discretization. (iii) The combination of velocity, pressure, and velocity gradient spaces is carefully chosen to avoid using stabilization which would introduce numerical dissipation. The implementation description details our choice of the orthonormal and degree-ordered basis for each quantity and the efficient local and global problem solution using them. Numerical experiments demonstrating the various features of the proposed method are presented. The features of this HDG method make it ideal for high-order LES of incompressible flows in complex geometries.</p>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 4","pages":"503-522"},"PeriodicalIF":1.7,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/fld.5369","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143533370","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}

{"title":"Perturbed Polynomial With Multiple Free-Parameters Reconstructed WENO Schemes","authors":"Yang Tao,&nbsp;Chen Xi,&nbsp;Wang Bo,&nbsp;Qijun Zhao,&nbsp;Guoqing Zhao","doi":"10.1002/fld.5370","DOIUrl":"https://doi.org/10.1002/fld.5370","url":null,"abstract":"<div>\u0000 \u0000 <p>The classical WENO schemes perform well for most flow field simulations, they may encounter the ‘Cannikin Law’ trap, that is, the lowest accuracy order of the scheme may have a significant influence on the simulation. In this article, a novel WENO scheme (termed HPWENO) with improved convergence order is proposed to alleviate this issue. The research in this article is structured around three key steps: Firstly, the stencil is classified as either smooth stencil or non-smooth stencil by using the classification strategy of the hybrid WENO scheme. Secondly, perturbed polynomial reconstruction with double free-parameters is proposed. Finally, the new reconstruction coefficients containing multiple free-parameters, built on the classical fifth-order WENO schemes, are obtained by using the perturbed polynomial reconstruction. Compared to the fifth-order WENO schemes, a maximum two-order of accuracy improvement in candidate stencils and one-order of accuracy improvement in global stencil can be achieved by adaptively adjusting the values of these free-parameters, resulting in sixth-order accuracy in global stencil and fifth-order accuracy in candidate stencils. Compared to the classical fifth-order WENO5-Z scheme and the WENO-AO(5,3) scheme, numerical examples show that the HPWENO schemes have higher convergence ratio, provide sharper solution profiles near discontinuities, and perform well in resolving small-scale structures. Compared to the sixth-order WENO-CU6 scheme and the seventh-order WENO7-Z scheme, the proposed HPWENO schemes outperform the two schemes in resolving the small-scale vortex of two-dimensional issues, and it saves approximately 15% and 25% of computational resources, respectively.</p>\u0000 </div>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 4","pages":"523-545"},"PeriodicalIF":1.7,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143533371","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}

{"title":"A Hybrid Method Combining Mimetic Finite Difference and Discontinuous Galerkin for Two-Phase Reservoir Flow Problems","authors":"Xiang Rao,&nbsp;Xupeng He,&nbsp;Hyung Kwak,&nbsp;Hussein Hoteit","doi":"10.1002/fld.5367","DOIUrl":"https://doi.org/10.1002/fld.5367","url":null,"abstract":"<div>\u0000 \u0000 <p>We introduce a new hybrid numerical approach that integrates the Mimetic Finite Difference (MFD) and Discontinuous Galerkin (DG) methods, termed the MFD-DG method. This technique leverages the MFD method to adeptly manage arbitrary quadrilateral meshes and full permeability tensors, addressing the flow equation for both edge-center and cell-center pressures. It also provides an approximation for phase fluxes across interfaces and within cells. Subsequently, the DG scheme, equipped with a slope limiter, is applied to the convection-dominated transport equation to compute nodal and cell-average water saturations. We present two numerical examples that demonstrate the MFD's capability to deliver high-precision approximations of pressure and flux distributions across a broad spectrum of grid types. Furthermore, our proposed hybrid MFD-DG method demonstrates a significantly enhanced ability to capture sharp water flooding fronts with greater accuracy compared to the traditional Finite Difference (FD) Method. To further demonstrate the efficacy of our approach, four numerical examples are provided to illustrate the MFD-DG method's superiority over the classical Finite Volume (FV) method and MFDM, particularly in scenarios characterized by anisotropic permeability tensors and intricate geometries.</p>\u0000 </div>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 4","pages":"484-502"},"PeriodicalIF":1.7,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143533358","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}

{"title":"The Matrix-Free Macro-Element Hybridized Discontinuous Galerkin Method for Steady and Unsteady Compressible Flows","authors":"Vahid Badrkhani,&nbsp;Marco F. P. ten Eikelder,&nbsp;René R. Hiemstra,&nbsp;Dominik Schillinger","doi":"10.1002/fld.5357","DOIUrl":"https://doi.org/10.1002/fld.5357","url":null,"abstract":"<p>The macro-element variant of the hybridized discontinuous Galerkin (HDG) method combines advantages of continuous and discontinuous finite element discretization. In this paper, we investigate the performance of the macro-element HDG method for the analysis of compressible flow problems at moderate Reynolds numbers. To efficiently handle the corresponding large systems of equations, we explore several strategies at the solver level. On the one hand, we utilize a second-layer static condensation approach that reduces the size of the local system matrix in each macro-element and hence the factorization time of the local solver. On the other hand, we employ a multi-level preconditioner based on the FGMRES solver for the global system that integrates well within a matrix-free implementation. In addition, we integrate a standard diagonally implicit Runge–Kutta scheme for time integration. We test the matrix-free macro-element HDG method for compressible flow benchmarks, including Couette flow, flow past a sphere, and the Taylor–Green vortex. Our results show that unlike standard HDG, the macro-element HDG method can operate efficiently for moderate polynomial degrees, as the local computational load can be flexibly increased via mesh refinement within a macro-element. Our results also show that due to the balance of local and global operations, the reduction in degrees of freedom, and the reduction of the global problem size and the number of iterations for its solution, the macro-element HDG method can be a competitive option for the analysis of compressible flow problems.</p>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 4","pages":"462-483"},"PeriodicalIF":1.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/fld.5357","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143533429","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}

{"title":"Comment on the Paper “A Two-Stage Reliable Computational Scheme for Stochastic Unsteady Mixed Convection Flow of Casson Nanofluid, Yasir Nawaz, Muhammad Shoaib Arif, Amna Nazeer, Javeria Nawaz Abbasi, Kamaleldin Abodayeh, International Journal for Numerical Methods in Fluids 2024;96:719–737”","authors":"Asterios Pantokratoras","doi":"10.1002/fld.5359","DOIUrl":"https://doi.org/10.1002/fld.5359","url":null,"abstract":"","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 5","pages":"675"},"PeriodicalIF":1.7,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143786937","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}

{"title":"Numerical Investigation and Machine Learning Predictions for Enhanced Thermal Management in Pulsating Heat Pipes: Modeling Turbulent Flow and Heat Transfer Characteristics in Nuclear Applications","authors":"Erfan Khosravian","doi":"10.1002/fld.5358","DOIUrl":"https://doi.org/10.1002/fld.5358","url":null,"abstract":"<div>\u0000 \u0000 <p>This paper presents a comprehensive numerical investigation of the performance of pulsating heat pipes (PHPs) within nuclear reactor cooling systems. A volume of fluid (VOF) method was used to simulate the complex multiphase flow, providing detailed insights into fluid distribution, phase interactions, and temperature variations under different operating conditions. The simulations revealed distinct phase separation and convective flow patterns that enhance heat transfer efficiency, which is critical for optimizing thermal management in nuclear reactors. Additionally, artificial neural network (ANN) models were employed to predict volume fractions and wall temperatures, achieving high accuracy with <i>R</i>² values of 0.99 and 0.98, respectively, and low mean absolute errors (MAE). The ANN models also reduced computational time by 90% compared to traditional numerical simulations. These findings highlight the potential of PHPs to improve heat transfer in nuclear systems and demonstrate the practicality of ANN models for real-time thermal optimization. The research contributes to enhancing the safety and efficiency of nuclear reactor cooling systems, with broader implications for thermal management across various engineering applications.</p>\u0000 </div>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 4","pages":"446-461"},"PeriodicalIF":1.7,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143536061","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}

{"title":"A Multi-Fidelity Model for Wave Energy Converters","authors":"Beatrice Battisti,&nbsp;Giovanni Bracco,&nbsp;Michel Bergmann","doi":"10.1002/fld.5354","DOIUrl":"https://doi.org/10.1002/fld.5354","url":null,"abstract":"<p>The objective of this study is to develop a three-dimensional numerical model for a floating point absorber wave energy converter in the presence of sea waves, considering its interaction with a bi-fluid flow (comprising air and water). The primary aim is to create an efficient computational tool that achieves two key objectives: firstly, reducing the computational time typically associated with high-fidelity Computational Fluid Dynamics (CFD) models, and secondly, curing the lack of accuracy of low-fidelity asymptotic or projection-based reduced-order models in regions subjected to viscous and highly nonlinear effects. To address these objectives, we propose a multi-fidelity model based on domain decomposition. This approach combines a high-fidelity CFD solver, which accurately captures the behavior in viscous and nonlinear regions, with a Reduced Order Model (ROM) based on Proper Orthogonal Decomposition (POD), tailored for weakly nonlinear regions. By integrating these components spatially, we simulate the dynamics of the floating body within a unified framework. This methodology ensures precise predictions of the body's motion for both in-sample (reproduction) and out-of-sample (prediction) configurations.</p>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 4","pages":"427-445"},"PeriodicalIF":1.7,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/fld.5354","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143536130","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}

{"title":"Novel Finite-Volume Complete Flux Approximation Schemes for the Incompressible Navier–Stokes Equations","authors":"Chitranjan Pandey,&nbsp;J. H. M. ten Thije Boonkkamp,&nbsp;B. V. Rathish Kumar","doi":"10.1002/fld.5353","DOIUrl":"https://doi.org/10.1002/fld.5353","url":null,"abstract":"<div>\u0000 \u0000 <p>We construct novel flux approximation schemes for the semidiscretized incompressible Navier–Stokes equations by finite-volume method on a staggered mesh. The calculation of the cell-face fluxes has been done by solving appropriate local <i>non-linear</i> boundary value problems (BVP). Consequently, the cell-face fluxes are represented as the sum of a homogeneous and an inhomogeneous flux; the homogeneous part represents the contribution of convection and viscous-friction, while the inhomogeneous part represents the contribution of the source terms. We derive three flux approximation schemes to include the impact of the source terms on the numerical fluxes. The first one is based on a homogeneous 1-D local BVP without source. The second scheme is based on an inhomogeneous 1-D local BVP considering only the pressure gradient term in the source. Finally, a complete flux scheme is derived which is based on an inhomogeneous 2-D local BVP. It takes into account both the gradient of the cross-flux and the pressure gradient in the source term. The numerical validation of the schemes is done for the benchmark lid-driven cavity flow for considerably high <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mtext>Reynolds</mtext>\u0000 </mrow>\u0000 <annotation>$$ mathrm{Reynolds} $$</annotation>\u0000 </semantics></math> numbers along with a numerical convergence test for the exact solution of the Taylor–Green vortex problem.</p>\u0000 </div>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 3","pages":"409-425"},"PeriodicalIF":1.7,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143117720","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}

{"title":"A Diffuse Interface Model for Cavitation, Taking Into Account Capillary Forces","authors":"Takfarines Ait-Ali,&nbsp;Sofiane Khelladi,&nbsp;Farid Bakir,&nbsp;Noureddine Hannoun,&nbsp;Xesús Nogueira,&nbsp;Luis Ramírez","doi":"10.1002/fld.5350","DOIUrl":"https://doi.org/10.1002/fld.5350","url":null,"abstract":"<div>\u0000 \u0000 <p>We consider the moving least squares method to solve compressible two-phase water-water vapor flow with surface tension. A diffuse interface model based on the Navier–Stokes and Korteweg equations is coupled with a suitable system of state equations that allows for a more realistic estimation of the pressure jump across the liquid–vapor interface as a function of temperature. We propose a simple formulation for computing the capillarity coefficient <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>λ</mi>\u0000 </mrow>\u0000 <annotation>$$ lambda $$</annotation>\u0000 </semantics></math> based on the surface tension and the thickness of the diffuse interface. A convergence analysis using pressure jump in the test case of static bubble is conducted to verify our solver. We present several numerical test cases that illustrate the ability of our model to reproduce qualitatively and quantitatively the effects of surface tension on cavitation bubbles in general situations.</p>\u0000 </div>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 3","pages":"395-408"},"PeriodicalIF":1.7,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143117049","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}