Article
Engineering, Multidisciplinary
Roberto J. Cier, Sergio Rojas, Victor M. Calo
Summary: The translated text describes a stable finite element formulation for advection-diffusion-reaction problems that allows for robust automatic adaptivity. The method efficiently demonstrates high applicability in various engineering applications.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2021)
Article
Computer Science, Interdisciplinary Applications
Qi Tang, Luis Chacon, Tzanio Kolev, John N. Shadid, Xian-Zhu Tang
Summary: This paper presents a high-order stabilized finite-element algorithm based on the MFEM finite element library for solving the reduced visco-resistive MHD equations. The use of physics-based preconditioning strategy and adaptive mesh refinement scheme is also discussed. Experimental results demonstrate the accuracy, efficiency, and scalability of the implicit scheme in the presence of large scale disparity.
JOURNAL OF COMPUTATIONAL PHYSICS
(2022)
Article
Computer Science, Interdisciplinary Applications
Manuela Bastidas, Carina Bringedal, Iuliu Sorin Pop, Florin Adrian Radu
Summary: The study introduces an efficient numerical strategy based on homogenization theory for solving non-linear parabolic problems in heterogeneous porous media, aiming to reduce computational complexity and maintain accuracy through local mesh refinement and error indicators.
JOURNAL OF COMPUTATIONAL PHYSICS
(2021)
Article
Mathematics, Applied
Ying Wang, Gang Wang, Feng Wang
Summary: This paper presents and analyzes a residual-type a posteriori error estimator for low-order virtual element discretization for the Stokes and Navier-Stokes problems, proving its globally upper and locally lower bounds for discretization error, with modifications for small viscosity cases. The effectiveness and flexibility of the designed error estimator combined with adaptive mesh refinement are verified through a series of benchmark tests.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2021)
Article
Engineering, Multidisciplinary
Chaemin Lee, Minam Moon, Jongho Park
Summary: This paper studies gradient smoothing methods (GSMs) with improved convergence behaviors for high-contrast problems such as the flow in heterogeneous porous media. The proposed GSM is adaptive to the heterogeneity of the problem and a multiscale variant is also introduced. The improved performance of the proposed methods is demonstrated through various numerical examples.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Article
Engineering, Multidisciplinary
Felix E. Kyburg, Sergio Rojas, Victor M. Calo
Summary: The study models incompressible Stokes flows using an adaptive stabilized finite element method, solving a discretely stable saddle-point problem for the velocity-pressure pair approximation. It analyzes the accuracy of different discrete velocity-pressure pairs in continuous finite element spaces, and validates the framework's performance with numerical examples.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING
(2022)
Article
Mechanics
Chiyu Xie, Wenhai Lei, Matthew T. Balhoff, Moran Wang, Shiyi Chen
Summary: The use of dispersed polymer microspheres in controlling preferential flow has proven to be more efficient and cost-effective than traditional methods by inducing pressure fluctuations to smartly control the flow. This intelligent mechanism allows for better performance in efficiency and economic aspects, with potential applications in enhancing oil recovery and soil wetting techniques.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mathematics, Applied
Niklas Kolbe, Nikolaos Sfakianakis
Summary: In this paper, we present an administration technique for the bookkeeping of adaptive mesh refinement on (hyper-)rectangular meshes. The technique provides a unified approach for h-refinement in different dimensions, simplifies the identification of siblings and neighboring cells, and has a small memory footprint. Its applications include addressing h-refinement and its benefits in a specific 2D tumor growth and invasion problem.
JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS
(2022)
Article
Geosciences, Multidisciplinary
Tao Huang, Xin Liao, Zhaoqin Huang, Renyi Wang
Summary: Ferrofluid, a magnetic fluid, has attracted extensive attention in the oil industry due to its controllable flow by an external magnetic field. Studies have shown that the flow of ferrofluid in complex porous media is significantly affected by magnetic force, offering potential for enhancing oil recovery efficiency in oil fields.
FRONTIERS IN EARTH SCIENCE
(2021)
Review
Chemistry, Physical
Abdulnaser M. Alshoaibi, Yahya Ali Fageehi
Summary: This paper introduces a robust algorithm for generating high-quality triangular meshes to model complex two-dimensional crack growth problems. The algorithm incorporates adaptive refinement and mesh structure updates near the crack tip to accurately predict crack growth path based on stress intensity factors. Experimental and numerical results demonstrate the effectiveness of the algorithm in accurately predicting crack growth and facilitating reliable stress analysis.
Article
Environmental Sciences
G. D. Beskardes, C. J. Weiss, K. L. Kuhlman, K. W. Chang
Summary: In this study, the hierarchical finite element method (Hi-FEM) is used to simulate fluid flow and heat conduction in complex geological environments. The method incorporates hierarchical basis functions and the Yeh's Galerkin model to accurately model fractured porous media, demonstrating its reliability in large-scale simulations with complex fracture networks.
WATER RESOURCES RESEARCH
(2022)
Article
Mathematics, Applied
Mahdi Jabbari, Hamid Moslemi
Summary: The adaptive finite element method aims to achieve the desired accuracy with fewer degrees of freedom by refining the mesh to distribute the error uniformly. Polygonal elements have gained attention due to their flexibility in complex geometries, with the Voronoi diagram being the most common approach for creating a polygonal mesh. However, the inconsistency between the generated mesh and the desired mesh density is a drawback. In this study, an iterative algorithm is used to optimize a target error function based on the generated and desired mesh densities at each Gauss point, while clustering and additional modification techniques are employed to improve the mesh quality.
FINITE ELEMENTS IN ANALYSIS AND DESIGN
(2022)
Article
Engineering, Manufacturing
Joan Baiges, Michele Chiumenti, Carlos A. Moreira, Miguel Cervera, Ramon Codina
Summary: An adaptive Finite Element strategy is introduced for numerical simulation of Additive Manufacturing processes, with a focus on Selective Laser Melting. The strategy involves octree-based mesh adaptivity and correction terms to compensate for accuracy loss in the coarsening process of the mesh, allowing for accurate results with reduced computational cost.
ADDITIVE MANUFACTURING
(2021)
Article
Computer Science, Interdisciplinary Applications
T. Kadeethum, H. M. Nick, S. Lee, F. Ballarin
Summary: This paper investigates the finite element method for the flow equation in Biot's system and proposes a novel enriched Galerkin method. In numerical experiments, the EG method shows similar pressure solution approximations to classical continuous Galerkin methods, but with fewer degrees of freedom compared to the discontinuous Galerkin method.
JOURNAL OF COMPUTATIONAL PHYSICS
(2021)
Article
Engineering, Marine
Zhao-Li Tian, A-Man Zhang, Yun-Long Liu, Longbin Tao
Summary: The study establishes a 3-D multi-fluid model based on the Eulerian finite element method and adaptive mesh refinement technique to investigate the evolution and motion of violent pulsating bubbles near a solid vertical wall. Through block-based adaptive mesh refinement, the simulation achieves a good balance between accuracy and efficiency, and is validated against underwater explosion experiments and existing numerical results. The complex physics of bubble motion, such as the formation of crescent-shaped bubbles and the nonlinear relationship between jet impact pressure and angles, are analyzed with different buoyancy parameters simulated.
Article
Green & Sustainable Science & Technology
Adriano Vinca, Simon Parkinson, Keywan Riahi, Edward Byers, Afreen Siddiqi, Abubakr Muhammad, Ansir Ilyas, Nithiyanandam Yogeswaran, Barbara Willaarts, Piotr Magnuszewski, Muhammad Awais, Andrew Rowe, Ned Djilali
Summary: The study highlights the water stress and energy insecurity in the Indus river basin in South Asia, emphasizing the importance of transboundary cooperation for more cost-effective and environmentally friendly development. By collaborating on water resources, electricity, and food production, the countries in the region could lower costs, reduce soil pollution, and mitigate water scarcity issues.
NATURE SUSTAINABILITY
(2021)
Article
Energy & Fuels
Shuaibin Wan, Xiongwei Liang, Haoran Jiang, Jing Sun, Ned Djilali, Tianshou Zhao
Summary: This study develops a novel framework that combines machine learning and genetic algorithm to optimize electrode structures for RFBs. By generating a custom dataset and utilizing machine learning models and genetic algorithm, hundreds of promising electrode structures with superior performance were successfully screened.
Article
Physics, Fluids & Plasmas
Antonio Bertei, Chih-Che Chueh, Roberto Mauri
Summary: The study investigates the phase separation process of a symmetric regular binary mixture subjected to constant shear and a temperature gradient using a thermodynamics-based phase-field model. The results show that the imposed temperature gradient causes complex droplet movement and coalescence, while different dimensionless numbers such as capillary and Lewis numbers have varying effects on phase separation.
PHYSICAL REVIEW FLUIDS
(2021)
Review
Environmental Sciences
Adriano Vinca, Keywan Riahi, Andrew M. Rowe, Ned Djilali
Summary: Approaches that integrate feedback between climate, land, energy and water have advanced significantly, but many nexus analyses overlook important inter-linkages. This review focuses on model accessibility, usability, and further model development opportunities, exploring where and why some nexus interactions are most relevant at different scales.
FRONTIERS IN ENVIRONMENTAL SCIENCE
(2021)
Article
Energy & Fuels
Jun-Yu Xie, Chih-Che Chueh, Wei-Hsin Chen, Kai-Jen Chen
Summary: This study investigated three different designs of flow channels in a printed circuit heat exchanger (PCHE) and validated their performance in efficiency and pressure drop through numerical simulations and experimental data. The results showed a significant improvement in heat transfer efficiency and pressure drop when using PCHE with zigzag flow channels, making it suitable for waste heat recovery systems in Organic Rankine Cycle (ORC).
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Thermodynamics
Chih-Chun Chang, Thomas Brousset, Chih-Che Chueh, Antonio Bertei
Summary: This study combines a packing algorithm with a finite difference solver to determine the effective thermal conductivity in composites with densely packed spherical phases, proposing three fit relations that show good accuracy for all conductivity ratios. These relations can also be used to estimate the effective electric conductivity, magnetic permeability and mass diffusivity in continuum regime, outperforming existing relations commonly used for the estimation of the effective thermal conductivity.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Chemistry, Multidisciplinary
Danny K. Long, Wolfgang Bangerth, Derek R. Handwerk, Christopher B. Whitehead, Patrick D. Shipman, Richard G. Finke
Summary: The study demonstrates the use of Bayesian inversion for statistical estimation of parameters in mechanism-enabled population balance models of nanoparticle growth. The results suggest that this method has significant value for parameter estimation in particle formation systems.
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2022)
Article
Mechanics
Chih-Che Chueh, Roberto Mauri, Antonio Bertei
Summary: The phase field approach is used to numerically simulate the detachment of a wall-bound 2D pendant drop in a fluid, and it is found that the onset of drop detachment can be described by a master curve.
Article
Mechanics
Ester Comellas, Jean-Paul Pelteret, Wolfgang Bangerth
Summary: A significant amount of time in computational modeling is spent on troubleshooting and debugging code. However, this process is rarely discussed, possibly due to the challenge of articulating it as it heavily relies on past failures. To assist newcomers in material modeling, this article provides guidance on identifying and fixing errors in computational solid mechanics models. It describes the components of a model and outlines potential sources of mistakes, emphasizing the importance of considering symptoms and offering strategies to pinpoint the problem area. The article also discusses how to maintain bug-free models during continual development. The collection of approaches and suggestions serves as a roadmap for finding and fixing mistakes in computational models, ensuring a smooth and enjoyable material modeling and simulation experience.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2023)
Article
Multidisciplinary Sciences
Teagan E. Bate, Megan E. Varney, Ezra H. Taylor, Joshua H. Dickie, Chih-Che Chueh, Michael M. Norton, Kun-Ta Wu
Summary: The study explores mixing dynamics of active fluids with spatiotemporally-varying activity levels. Results show a transition from diffusion-like to superdiffusion-like behaviors, with mixing efficacy depending on the Peclet number and spatial distribution of activities. Active fluid mixing involves complex coupling between active stress distribution and ATP transport.
NATURE COMMUNICATIONS
(2022)
Article
Computer Science, Software Engineering
Marc Fehling, Wolfgang Bangerth
Summary: The hp-adaptive finite element method, which allows for independent selection of mesh size (h) and polynomial degree (p) for each cell, is known to have better theoretical convergence properties. However, its implementation is hindered by challenging algorithms and lack of widely usable implementations, especially for continuous finite elements. This study discusses necessary algorithms for a comprehensive and generic implementation of hp-adaptive finite element methods on distributed-memory, parallel machines, demonstrating performance with numerical examples.
ACM TRANSACTIONS ON MATHEMATICAL SOFTWARE
(2023)
Article
Engineering, Chemical
Chih-Chun Chang, Chih-Che Chueh
Summary: In this study, three-dimensional microstructures of sintered core-shell spheres with different shell thicknesses and degrees of densification were generated using a drop-and-roll algorithm and a newly developed core-shell generation method. The effective conductivity of each microstructure was obtained using open-source software and compared with existing models. The results showed underprediction at core-shell volume fractions ϕ = 0.6-0.75 and overprediction at ϕ>0.85. Additionally, unique conductive ring and straight line patterns were observed in the heat flux calculation, indicating the presence of inhomogeneity in core-shell structures.
Article
Computer Science, Interdisciplinary Applications
Geng-Chun Kuo, Jun-Yu Xie, Chih-Che Chueh
Summary: The performance of a printed circuit heat exchanger (PCHE) with NACA 0020 airfoil overlap fins in its flow channels was numerically investigated. Optimized overlapping fin design showed lower pressure drops and higher convective heat flux compared to separate fins. The use of specific overlapping fin parameters resulted in comparable effectiveness and a 22% decrease in pressure drop.
ENGINEERING REPORTS
(2023)
Article
Thermodynamics
Chih-Che Chueh, Shao-Che Hung
Summary: This study numerically investigates the melting process of a phase change material in an H-type finned concentric shell tube configuration. The results show that the phase change material in the 3 mm fin tube exhibits significantly faster melting rates compared to narrower fin tubes. Additionally, specific ratios of curvy angles in the fin structure are found to increase total energy stored and improve melting performance.
APPLIED THERMAL ENGINEERING
(2024)
Article
Engineering, Mechanical
Orhan Atabay, Ned Djilali, Curran Crawford
Summary: This study examines the long-term energy use implications of electrification, automation, and sharing of road vehicles in British Columbia, Canada. It analyzes energy use from 1990 to 2016 and presents hypothetical scenarios incorporating various effects of vehicle electrification, sharing, and automation. The study compares transportation energy use projections to those of the Canadian Energy Regulator (CER) and finds higher energy savings in the scenarios that consider vehicle electrification. Combining vehicle electrification and automation leads to decreased energy use in all scenarios, surpassing the CER's projections. The inclusion of other technology disruptions and the effects of pandemics further reduce transportation demand and provide additional energy savings.
Article
Computer Science, Interdisciplinary Applications
Jin Bao, Zhaoli Guo
Summary: At the equilibrium state of a two-phase fluid system, the chemical potential is constant and the velocity is zero. However, it is challenging to capture this equilibrium state accurately in numerical simulations, resulting in inconsistent thermodynamic interfacial properties and spurious velocities. Therefore, numerical schemes with well-balanced properties are preferred for simulating two-phase flows.
COMPUTERS & FLUIDS
(2024)
Article
Computer Science, Interdisciplinary Applications
Brian C. Vermeire
Summary: This study presents a framework for implicit large eddy simulation (ILES) of incompressible flows by combining the entropically damped artificial compressibility (EDAC) method with the flux reconstruction (FR) approach. Experimental results demonstrate that the method is accurate and stable for low-order solutions, while higher-order solutions exhibit significantly higher accuracy and lower divergence error compared to reference direct numerical simulation.
COMPUTERS & FLUIDS
(2024)
Article
Computer Science, Interdisciplinary Applications
Mijian Li, Rui Wang, Xinyu Guo, Xinyu Liu, Lianzhou Wang
Summary: In this study, the flow mechanisms around wall-mounted structures were investigated using Large Eddy Simulation (LES). The impact of inflow turbulence on the flow physics, dynamic response, and hydrodynamic performance was explored. The results revealed strong interference between velocity fluctuations and the wake past the cylinder, as well as significant convection effects in the far wake region.
COMPUTERS & FLUIDS
(2024)
Article
Computer Science, Interdisciplinary Applications
Donatella Passiatore, Luca Sciacovelli, Paola Cinnella, Giuseppe Pascazio
Summary: A high-order shock-capturing central finite-difference scheme is evaluated for numerical simulations of hyper-sonic high-enthalpy flows out of thermochemical equilibrium. The scheme utilizes a tenth-order accurate central-difference approximation of inviscid fluxes, along with high-order artificial dissipation and shock-capturing terms. The proposed approach demonstrates accuracy and robustness for a variety of thermochemical non-equilibrium configurations.
COMPUTERS & FLUIDS
(2024)
Article
Computer Science, Interdisciplinary Applications
Philipp Bahavar, Claus Wagner
Summary: Condensation is an important aspect in flow applications, and simulating the gas phase and tracking the deposition rates of condensate droplets can capture the effects of surface droplets on the flow while reducing computational costs.
COMPUTERS & FLUIDS
(2024)
Article
Computer Science, Interdisciplinary Applications
Andras Szabo, Gyorgy Paal
Summary: This paper introduces an efficient calculation method, the parabolized stability equations (PSE), for solving stability equations. By calculating LU factorization once in each marching step, the time spent on solving linear systems of equations can be significantly reduced. Numerical experiments demonstrate the effectiveness of this method in reducing the solution time for linear equations, and its applicability to similar problems.
COMPUTERS & FLUIDS
(2024)
Article
Computer Science, Interdisciplinary Applications
A. Khalifa, M. Breuer
Summary: This study evaluates a recently developed data-driven model for collision-induced agglomerate breakup in high mass loading flows. The model uses artificial neural networks to predict the post-collision behavior of agglomerates, reducing computational costs compared to coupled CFD-DEM simulations.
COMPUTERS & FLUIDS
(2024)
Article
Computer Science, Interdisciplinary Applications
Chunmei Du, Maojun Li
Summary: This paper considers the bilayer shallow water wave equations in one-dimensional space and presents an invariant domain preserving DG method to avoid Kelvin-Helmholtz instability.
COMPUTERS & FLUIDS
(2024)
Article
Computer Science, Interdisciplinary Applications
Jean-Michel Tucny, Mihir Durve, Andrea Montessori, Sauro Succi
Summary: The prediction of non-equilibrium transport phenomena in disordered media is a challenging problem for conventional numerical methods. Physics-informed neural networks (PINNs) show potential for solving this inverse problem. In this study, PINNs were used to successfully predict the velocity field of rarefied gas flow, and AdamW was found to be the best optimizer.
COMPUTERS & FLUIDS
(2024)
Article
Computer Science, Interdisciplinary Applications
Min Gao, Pascal Mossier, Claus-Dieter Munz
Summary: In recent decades, the arbitrary Lagrangian-Eulerian (ALE) approach has gained popularity in dealing with fluid flows with moving boundaries. This paper presents a novel algorithm that combines the ALE finite volume (FV) and ALE discontinuous Galerkin (DG) methods into a stable and efficient hybrid approach. The main challenge of this mixed ALE FV and ALE DG method is reducing the inconsistency between the two discretizations. The proposed algorithm is implemented into a loosely-coupled fluid-structure interaction (FSI) framework and is demonstrated through various benchmark test cases and complex scenarios.
COMPUTERS & FLUIDS
(2024)
Article
Computer Science, Interdisciplinary Applications
Dawid Strzelczyk, Maciej Matyka
Summary: In this study, the numerical convergence of the Meshless Lattice Boltzmann Method (MLBM) is investigated through three benchmark tests. The results are compared to the standard Lattice Boltzmann Method (LBM) and the analytical solution of the Navier-Stokes equation. It is found that MLBM outperforms LBM in terms of error value for the same number of nodes discretizing the domain.
COMPUTERS & FLUIDS
(2024)
Article
Computer Science, Interdisciplinary Applications
Kanishka Bhattacharya, Tapan Jana, Amit Shaw, L. S. Ramachandra, Vishal Mehra
Summary: In this work, an adaptive algorithm is developed to address the issue of tensile instability in Smoothed Particle Hydrodynamics (SPH) by adjusting the shape of the kernel function to satisfy stability conditions. The effectiveness of the algorithm is demonstrated through dispersion analysis and fluid dynamics simulations.
COMPUTERS & FLUIDS
(2024)
Article
Computer Science, Interdisciplinary Applications
Luis Laguarda, Stefan Hickel
Summary: We propose several enhancements to improve the accuracy and performance of the digital filter turbulent inflow generation technique, such as introducing a more realistic correlation function and varying target length scales. Additionally, we suggest generating inflow data in parallel at a prescribed time interval to improve computational performance. Based on the results of large-eddy simulations, these enhancements have shown to be beneficial. Suppressing streamwise velocity fluctuations at the inflow leads to the fastest relaxation of pressure fluctuations. However, this approach increases the adaptation length, which can be shortened by artificially increasing the wall-normal Reynolds stresses.
COMPUTERS & FLUIDS
(2024)
Article
Computer Science, Interdisciplinary Applications
Constantin Zenz, Michele Buttazzoni, Tobias Florian, Katherine Elizabeth Crespo Armijos, Rodrigo Gomez Vazquez, Gerhard Liedl, Andreas Otto
Summary: A new model for compressible multiphase flows involving sharp interfaces and phase change is presented, with a focus on the treatment of compressibility and phase change in the multiphase fluid flow model. The model's accuracy and suitability are demonstrated through comparisons with experimental observations.
COMPUTERS & FLUIDS
(2024)
Article
Computer Science, Interdisciplinary Applications
Joseph O'Connor, Sylvain Laizet, Andrew Wynn, Wouter Edeling, Peter V. Coveney
Summary: This article aims to apply uncertainty quantification and sensitivity analysis to the direct numerical simulation (DNS) of low Reynolds number wall-bounded turbulent channel flow. By using a highly scalable DNS framework and UQ techniques, the study evaluates the influence of different numerical parameters on the simulation results without explicitly modifying the code. The findings provide guidance for numerical simulations of wall-bounded turbulent flows.
COMPUTERS & FLUIDS
(2024)
