International Journal for Numerical Methods in Fluids最新文献_第3页

The Matrix-Free Macro-Element Hybridized Discontinuous Galerkin Method for Steady and Unsteady Compressible Flows 定常和非定常可压缩流动的无矩阵宏元杂化不连续伽辽金法

IF 1.7 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2024-12-01 DOI: 10.1002/fld.5357

Vahid Badrkhani, Marco F. P. ten Eikelder, René R. Hiemstra, Dominik Schillinger

{"title":"The Matrix-Free Macro-Element Hybridized Discontinuous Galerkin Method for Steady and Unsteady Compressible Flows","authors":"Vahid Badrkhani, Marco F. P. ten Eikelder, René R. Hiemstra, 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}

引用次数: 0

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” 论文《Casson纳米流体随机非定常混合对流的两阶段可靠计算方案》，Yasir Nawaz, Muhammad Shoaib Arif, Amna Nazeer, Javeria Nawaz Abbasi, Kamaleldin Abodayeh，国际流体数值方法学报，2024;96:719-737》

IF 1.7 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2024-11-28 DOI: 10.1002/fld.5359

Asterios Pantokratoras

引用次数: 0

Numerical Investigation and Machine Learning Predictions for Enhanced Thermal Management in Pulsating Heat Pipes: Modeling Turbulent Flow and Heat Transfer Characteristics in Nuclear Applications 脉动热管中增强热管理的数值研究和机器学习预测：模拟核应用中的湍流和传热特性

IF 1.7 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2024-11-22 DOI: 10.1002/fld.5358

Erfan Khosravian

{"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><sup>2</sup> 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}

引用次数: 0

A Multi-Fidelity Model for Wave Energy Converters 波浪能转换器的多保真度模型

IF 1.7 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2024-11-21 DOI: 10.1002/fld.5354

Beatrice Battisti, Giovanni Bracco, Michel Bergmann

{"title":"A Multi-Fidelity Model for Wave Energy Converters","authors":"Beatrice Battisti, Giovanni Bracco, 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}

引用次数: 0

Novel Finite-Volume Complete Flux Approximation Schemes for the Incompressible Navier–Stokes Equations

IF 1.7 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2024-11-21 DOI: 10.1002/fld.5353

Chitranjan Pandey, J. H. M. ten Thije Boonkkamp, B. V. Rathish Kumar

{"title":"Novel Finite-Volume Complete Flux Approximation Schemes for the Incompressible Navier–Stokes Equations","authors":"Chitranjan Pandey, J. H. M. ten Thije Boonkkamp, 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}

引用次数: 0

A Diffuse Interface Model for Cavitation, Taking Into Account Capillary Forces

IF 1.7 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2024-11-20 DOI: 10.1002/fld.5350

Takfarines Ait-Ali, Sofiane Khelladi, Farid Bakir, Noureddine Hannoun, Xesús Nogueira, Luis Ramírez

{"title":"A Diffuse Interface Model for Cavitation, Taking Into Account Capillary Forces","authors":"Takfarines Ait-Ali, Sofiane Khelladi, Farid Bakir, Noureddine Hannoun, Xesús Nogueira, 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}

引用次数: 0

A Time-Space Dual Adaptive Uncoupled Method for Supersonic Combustion

IF 1.7 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2024-11-18 DOI: 10.1002/fld.5351

Junjie Wu, Xun Xu, Xuke Zhang, Bin Zhang

{"title":"A Time-Space Dual Adaptive Uncoupled Method for Supersonic Combustion","authors":"Junjie Wu, Xun Xu, Xuke Zhang, Bin Zhang","doi":"10.1002/fld.5351","DOIUrl":"https://doi.org/10.1002/fld.5351","url":null,"abstract":"<div>\u0000 \u0000 <p>High computational complexity due to rapidly increasing numerical stiffness is a difficult problem for simulating a supersonic reactive flow by using the uncoupled method. On the basis of our previous work, this paper proposes a dual adaptive method to ensure high calculation efficiency and good robustness in simulating stiff cases. The principle of this method is to realize adaptive coordination for the advection and reaction time steps in accordance with the non-uniform feature of stiffness in the space and time dimensions. The proposed method can advance by a small time step in strong stiffness while with a large one in weak stiffness through the “prediction-correction-recovery” strategy. Some classical problems are chosen to verify the performance of the proposed method. The proposed method improved the computation efficiency by at least <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>30</mn>\u0000 <mo>%</mo>\u0000 </mrow>\u0000 <annotation>$$ 30% $$</annotation>\u0000 </semantics></math> comparing with the previous method [1] and widened the error tolerance of the initial time step.</p>\u0000 </div>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 3","pages":"378-394"},"PeriodicalIF":1.7,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143116441","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

Fully Coupled, Higher-Order, Block-Structured Mesh Generation in Fluid–Structure Interaction

IF 1.7 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2024-11-14 DOI: 10.1002/fld.5355

Teresa Schwentner, Thomas-Peter Fries

引用次数: 0

Sim-Net: Simulation Net for Solving Seepage Equation Under Unsteady Boundary

IF 1.7 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2024-11-13 DOI: 10.1002/fld.5356

Daolun Li, Enyuan Chen, Yantao Xu, Wenshu Zha, Luhang Shen, Dongsheng Chen

{"title":"Sim-Net: Simulation Net for Solving Seepage Equation Under Unsteady Boundary","authors":"Daolun Li, Enyuan Chen, Yantao Xu, Wenshu Zha, Luhang Shen, Dongsheng Chen","doi":"10.1002/fld.5356","DOIUrl":"https://doi.org/10.1002/fld.5356","url":null,"abstract":"<div>\u0000 \u0000 <p>The seepage equation plays a crucial role in fields such as groundwater management, petroleum engineering, and civil engineering. Currently, physical-informed neural networks (PINNs) have become an effective tool for solving seepage equations. However, practical applications often involve variable flow rates, which pose significant challenges for using neural networks to find solutions. Inspired by Deep Operator Network (DeepONet), this paper proposes a new model named Simulation Net (Sim-net) to deal with unsteady sources or sinks problems. Sim-net is designed to simulate and solve seepage equations without the need for retraining. This model integrates potential spatial and temporal features based on spatial pressure distribution and well bottom–hole pressure, respectively, which serve as additional signposts to guide neural networks in approximating seepage equations. Sim-net exhibits transfer learning capabilities, enabling it to handle variable flow rate problems without retraining for new flow conditions. Numerical experiments demonstrate that the trained model can directly solve seepage equations without the need for retraining, indicating its superior applicability compared to existing PINNs-based methods. Additionally, in comparison to the DeepONet, Sim-net achieves higher accuracy.</p>\u0000 </div>","PeriodicalId":50348,"journal":{"name":"International Journal for Numerical Methods in Fluids","volume":"97 3","pages":"345-358"},"PeriodicalIF":1.7,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143114554","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

Numerical Prediction of Cavitation Erosion Risk Based on a New Erosion Indicator

IF 1.7 4区工程技术

International Journal for Numerical Methods in Fluids Pub Date : 2024-11-09 DOI: 10.1002/fld.5347

Xiaoyu Wang, Junqi Ma, Tian Wang, Qiang Sun

引用次数: 0