Article
Computer Science, Interdisciplinary Applications
Asim Onder, Philip L. -F. Liu
Summary: Estimating interface curvature in surface-tension dominated flows is a challenge in Volume of Fluid (VOF) methods. Data-driven methods offer promise but suffer from divergence with grid refinement and failure to capture symmetry patterns. This study proposes a new data-driven strategy using neural networks to conserve symmetries and deliver consistent results over various grids. Testing against conventional schemes shows superior performance, accuracy, and convergence properties despite using smaller stencil.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Engineering, Mechanical
Faroogh Garoosi, Kamel Hooman
Summary: The study aims to improve the stability and accuracy of the Volume-of-Fluid (VOF) method for simulating multiphase flow problems with large density ratios and moving interfaces. By introducing a novel high-order TVD flux-limiter scheme, modifying the PISO algorithm according to the SIMPLER algorithm, and adopting the PLIC algorithm for interface treatment, the proposed modifications have been verified to effectively handle violent free-surface flows involving interface rupture and coalescence.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Computer Science, Interdisciplinary Applications
Joaquin Lopez, Julio Hernandez
Summary: The gVOF package implements accurate and efficient geometric volume of fluid (VOF) methods on arbitrary grids, either structured or unstructured, based on multidimensional unsplit advection and piecewise linear interface calculation (PLIC) schemes. It aims to facilitate and extend the use of advanced unsplit geometric VOF methods in computational fluid dynamics codes. The package includes a complete set of routines for VOF initialization, interface reconstruction, and fluid advection, and utilizes external libraries for analytical and geometrical operations. The package demonstrates outstanding performance in terms of efficiency and accuracy compared to other advanced geometric VOF methods.
COMPUTER PHYSICS COMMUNICATIONS
(2022)
Article
Engineering, Chemical
Ahmad Amani, Jordi Muela, Eugenio Schillaci, Jesus Castro
Summary: This article introduces the application of the VOF method based on the PLIC reconstruction algorithm in numerical simulation of interfacial flows, and proposes a method for evaluating the geometric properties of the interface based on a triangular grid. By comparing with commonly used methods, it is found that the proposed methods in this article have significant improvements in calculation accuracy and spatial convergence errors.
Article
Thermodynamics
S. P. Shipkowski, I Perez-Raya
Summary: This article introduces a new method for calculating interface size in computational fluid dynamics simulations, namely the PLIC-ASB method. This method uses a symbolic equation instead of approximation or numerical methods to maintain a sharp interface and provide physics-based mass transfer. Compared to the VOF gradient method, the PLIC-ASB method demonstrates higher accuracy and smaller relative error.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Computer Science, Interdisciplinary Applications
Johannes Kromer, Dieter Bothe
Summary: The algorithm introduced in this work efficiently solves the problem of finding a plane with a given normal vector. The combination of recursive Gaussian divergence theorem and dynamic choice of coordinate origin results in significant improvement in computational efficiency and performance.
JOURNAL OF COMPUTATIONAL PHYSICS
(2022)
Article
Mechanics
Van-Tu Nguyen, Thanh-Hoang Phan, Trong-Nguyen Duy, Dong-Hyun Kim, Warn-Gyu Park
Summary: This study investigated the dynamic behavior of bubble collapses near walls and a free surface using numerical simulation, validating the results with experiments and providing important references for exploring phenomena related to bubble collapse.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2022)
Article
Mechanics
Johanna Potyka, Kathrin Schulte
Summary: This paper presents an advanced Volume of Fluid (VOF) method for performing three-dimensional Direct Numerical Simulations (DNS) of the interaction of two immiscible fluids in a gaseous environment with large topology changes. The method includes efficient reconstruction of phase boundaries near the triple line using a Piecewise Linear Interface Calculation (PLIC) method and enhanced surface force modeling with the Continuous Surface Stress (CSS) model. Implementation of these methods in the multi-phase flow solver Free Surface 3D (FS3D) yielded successful validation. The simulations provide valuable insights into the collision process and can support future modeling of immiscible liquid interaction.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2024)
Article
Engineering, Multidisciplinary
Zeeshan Ahmad Khan, Naseem Ahmad, Mariyam Sattar, Mohd Anul Haq, Ilyas Khan, Abdul Hamid Ganie
Summary: This study proposes an algorithm for accurately simulating bubble growth and addresses the issue of interface deformation in the Volume of Fluid (VOF) interface tracking method. The proposed method is validated through comparisons with theoretical and experimental results, showing good predictive accuracy and parameter consistency. Additionally, the simulation provides insights into temperature and velocity fields that cannot be directly obtained through experiments.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Chemistry, Physical
Faroogh Garoosi, Tew-Fik Mahdi
Summary: This study describes the application of the improved Volume-Of-Fluid (VOF) method in various problems and provides benchmarking tools for validating existing numerical models and code verification. The performance and accuracy of the method are demonstrated through a series of test cases, showing its superiority and versatility in handling multiphase flows.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Engineering, Chemical
Johan Sarache Pina, Dario Godino, Santiago Corzo, Damian Ramajo
Summary: In this study, a novel test involving fast air injection into a vertical water column was experimentally and numerically studied. The results showed that the Volume of Fluid (VOF) method had good agreement with the experiments, while the Eulerian Two-Fluid (TF) method had some limitations.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Mechanics
Sina Alavi, Mohammad Passandideh-Fard, Javad Mostaghimi
Summary: A numerical method is developed to model the deformation of interfaces between various materials in a multimaterial system. The method combines a new and intuitive interface reconstruction scheme with the volume-of-fluid (VOF) technique capable of addressing triple-point configurations. It can track various interfacial structures between liquids in liquid-liquid-gas systems. The method is validated through standard test cases and compared with experimental results of water drop impact on silicone oil.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2023)
Article
Engineering, Mechanical
Pedro Ricardo C. Souza, Helio Ribeiro Neto, Millena Martins Villar, Joao Marcelo Vedovotto, Aldemir Ap Cavalini Jr, Aristeu Silveira Neto
Summary: In this study, the authors aim to solve incompressible fluid-structure interaction problems in multi-phase flows using a partitioned approach. They develop a three-dimensional, block-structured, adaptive mesh refinement (AMR) code called MFSim. The simulation uses a projection method for large eddy simulation (LES) of Navier-Stokes equations and a VOF-PLIC method with finite volume discretization. The results show good agreement with experimental data.
JOURNAL OF THE BRAZILIAN SOCIETY OF MECHANICAL SCIENCES AND ENGINEERING
(2022)
Article
Mechanics
An Liu, Dongliang Sun, Bo Yu, Jinjia Wei, Zhizhu Cao
Summary: The study introduces an adaptive coupled volume-of-fluid and level set (VOSET) method based on unstructured grids for simulating incompressible interfacial flows. Through validation with four classical test cases, it is found that the adaptive VOSET algorithm enhances accuracy near the interface, particularly in capturing curvature and surface tension, while also improving computational efficiency by significantly reducing the number of grid cells.Comparatively, the adaptive VOSET requires only 4.85%-24.5% of the number of adaptive grid cells and 5.31%-15.93% of the computational time compared to fixed unstructured grid cells, demonstrating outstanding properties in terms of time and computational cost savings.
Article
Computer Science, Interdisciplinary Applications
Johannes Kromer, Fabio Leotta, Dieter Bothe
Summary: This paper introduces a new method for computing accurate normal fields from volume fractions on unstructured polyhedral meshes. The method achieves second-order accuracy for surfaces with significant curvature variation and first-order accuracy for normal field angular deviation. By fitting a plane to the volume fraction data of neighboring cells, an averaged normal is computed locally in each mesh cell, while considering volume conservation. The resulting minimization problem is approximately solved using a Newton-type method, and the regularity and error measures are discussed. Numerical results and convergence studies demonstrate the effectiveness of the method.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Thermodynamics
Lubomir Bures, Yohei Sato
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2020)
Article
Mechanics
Lubomir Bures, Yohei Sato
Summary: This study describes the formation of a microlayer in nucleate boiling as a dewetting transition in the presence of phase change, and develops a new formulation for the transition criterion based on a synthesis of existing theoretical, experimental and numerical data. The new criterion shows very good agreement with reference data from a dewetting experiment of a volatile liquid and results from a high-resolution direct numerical simulation of nucleate boiling, particularly for Jakob numbers around 75 which cover many important boiling situations.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Thermodynamics
Lubomir Bures, Yohei Sato
Summary: This paper presents a coupling of the geometric Volume-of-Fluid (VOF) method with a sharp-interface phase-change model for accurate resolution of multiphase problems. Verification cases demonstrate the method's performance and feasibility, marking an important step in the development of multiphase codes capable of accurately resolving complex three-dimensional multiphase flows.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Engineering, Marine
Alen Cukrov, Yohei Sato, Ivanka Boras, Bojan Niceno
Summary: This paper presents a novel approach for solving the Stefan problem within the framework of the multi-fluid model supplemented with the Volume of Fluid (VOF) method, known as two-fluid VOF. The method involves writing mass, momentum, and energy conservation equations on a per-phase basis and supplementing them with closure models via source terms. Heat and mass transfer calculations are based on a fictitious function of the heat transfer coefficient, which depends on local cell size and thermal conductivity, making implementation straightforward by using local values instead of global parameters. The sharpness of the interface is ensured through a geometrical reconstruction scheme implemented in VOF.
Article
Mechanics
Lubomir Bures, Yohei Sato
Summary: The dynamics of the microlayer beneath a growing bubble in nucleate boiling significantly affect the heat-transfer characteristics of the process. In this study, a computational strategy utilizing direct numerical simulation (DNS) is developed to model nucleate boiling and explicitly resolve the microlayer. Closure models for interfacial heat transfer and dynamic contact angle are introduced and validated. The results show good agreement with experimental data and a sensitivity study reveals the dependence of microlayer thickness on superheat and fluid properties. The study also presents a demonstration of DNS with an explicitly resolved microlayer in three-dimensional Cartesian coordinates.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Engineering, Civil
Maurice Bizzozero, Yohei Sato, Mohamed Aly Sayed
Summary: This study investigates the aerodynamic performance of a Hyperloop pod equipped with an axial compressor using CFD simulation. The results show that the compressor can reduce drag when the pod exceeds the Kantrowitz Limit, leading to a decrease in power consumption.
JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS
(2021)
Article
Multidisciplinary Sciences
Michal W. Kepa, Takashi Tomizaki, Yohei Sato, Dmitry Ozerov, Hiroshi Sekiguchi, Nobuhiro Yasuda, Koki Aoyama, Petr Skopintsev, Jorg Standfuss, Robert Cheng, Michael Hennig, Soichiro Tsujino
Summary: Acoustic levitation plays a crucial role in chemical and biochemical analysis, but loading high viscosity samples is challenging. By using polymer thin films as sample holders and studying their acoustic levitation and rotation, it is possible to achieve controlled rotation and positional stability for the samples.
SCIENTIFIC REPORTS
(2022)
Article
Physics, Applied
Shichao Jia, Yohei Sato, Soichiro Tsujino
Summary: The controlled rotation of acoustically levitated samples is beneficial for analyzing sample properties, and the study finds that short blades play an essential role in producing the acoustic torque.
APPLIED PHYSICS LETTERS
(2022)
Article
Nuclear Science & Technology
Daniel Vlcek, Yohei Sato
Summary: The developed CTU-PSI model is applicable to boiling in PWRs and utilizes quantitative 3D measurements and rates to study trends. Although the widely used RPI model provides predictions for saturated and subcooled boiling, it still faces difficulties in accurately predicting the heat transfer coefficient and DNB due to its submodels' empirical correlations and limitations. Additionally, the fixed vapor temperature in the RPI model does not reflect real boiling flow, which can be addressed by the extended non-equilibrium subcooled boiling model.
NUCLEAR ENGINEERING AND DESIGN
(2023)
Article
Computer Science, Interdisciplinary Applications
Tian Liang, Lin Fu
Summary: In this work, a new shock-capturing framework is proposed based on a new candidate stencil arrangement and the combination of infinitely differentiable non-polynomial RBF-based reconstruction in smooth regions with jump-like non-polynomial interpolation for genuine discontinuities. The resulting scheme achieves high order accuracy and resolves genuine discontinuities with sub-cell resolution.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Lukas Lundgren, Murtazo Nazarov
Summary: In this paper, a high-order accurate finite element method for incompressible variable density flow is introduced. The method addresses the issues of saddle point system and stability problem through Schur complement preconditioning and artificial compressibility approaches, and it is validated to have high-order accuracy for smooth problems and accurately resolve discontinuities.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Gabriele Ciaramella, Laurence Halpern, Luca Mechelli
Summary: This paper presents a novel convergence analysis of the optimized Schwarz waveform relaxation method for solving optimal control problems governed by periodic parabolic PDEs. The analysis is based on a Fourier-type technique applied to a semidiscrete-in-time form of the optimality condition, which enables a precise characterization of the convergence factor at the semidiscrete level. The behavior of the optimal transmission condition parameter is also analyzed in detail as the time discretization approaches zero.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Jonas A. Actor, Xiaozhe Hu, Andy Huang, Scott A. Roberts, Nathaniel Trask
Summary: This article introduces a scientific machine learning framework that uses a partition of unity architecture to model physics through control volume analysis. The framework can extract reduced models from full field data while preserving the physics. It is applicable to manifolds in arbitrary dimension and has been demonstrated effective in specific problems.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Nozomi Magome, Naoki Morita, Shigeki Kaneko, Naoto Mitsume
Summary: This paper proposes a novel strategy called B-spline based SFEM to fundamentally solve the problems of the conventional SFEM. It uses different basis functions and cubic B-spline basis functions with C-2-continuity to improve the accuracy of numerical integration and avoid matrix singularity. Numerical results show that the proposed method is superior to conventional methods in terms of accuracy and convergence.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Timothy R. Law, Philip T. Barton
Summary: This paper presents a practical cell-centred volume-of-fluid method for simulating compressible solid-fluid problems within a pure Eulerian setting. The method incorporates a mixed-cell update to maintain sharp interfaces, and can be easily extended to include other coupled physics. Various challenging test problems are used to validate the method, and its robustness and application in a multi-physics context are demonstrated.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Xing Ji, Fengxiang Zhao, Wei Shyy, Kun Xu
Summary: This paper presents the development of a third-order compact gas-kinetic scheme for compressible Euler and Navier-Stokes solutions, constructed particularly for an unstructured tetrahedral mesh. The scheme demonstrates robustness in high-speed flow computation and exhibits excellent adaptability to meshes with complex geometrical configurations.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Alsadig Ali, Abdullah Al-Mamun, Felipe Pereira, Arunasalam Rahunanthan
Summary: This paper presents a novel Bayesian statistical framework for the characterization of natural subsurface formations, and introduces the concept of multiscale sampling to localize the search in the stochastic space. The results show that the proposed framework performs well in solving inverse problems related to porous media flows.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Jacob Rains, Yi Wang, Alec House, Andrew L. Kaminsky, Nathan A. Tison, Vamshi M. Korivi
Summary: This paper presents a novel method called constrained optimized DMD with Control (cOptDMDc), which extends the optimized DMD method to systems with exogenous inputs and can enforce the stability of the resulting reduced order model (ROM). The proposed method optimally places eigenvalues within the stable region, thus mitigating spurious eigenvalue issues. Comparative studies show that cOptDMDc achieves high accuracy and robustness.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Andrea La Spina, Jacob Fish
Summary: This work introduces a hybridizable discontinuous Galerkin formulation for simulating ideal plasmas. The proposed method couples the fluid and electromagnetic subproblems monolithically based on source and employs a fully implicit time integration scheme. The approach also utilizes a projection-based divergence correction method to enforce the Gauss laws in challenging scenarios. Numerical examples demonstrate the high-order accuracy, efficiency, and robustness of the proposed formulation.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Junhong Yue, Peijun Li
Summary: This paper proposes two numerical methods (IP-FEM and BP-FEM) to study the flexural wave scattering problem of an arbitrary-shaped cavity on an infinite thin plate. These methods successfully decompose the fourth-order plate wave equation into the Helmholtz and modified Helmholtz equations with coupled conditions on the cavity boundary, providing an effective solution to this challenging problem.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
William Anderson, Mohammad Farazmand
Summary: We develop fast and scalable methods, called RONS, for computing reduced-order nonlinear solutions. These methods have been proven to be highly effective in tackling challenging problems, but become computationally prohibitive as the number of parameters grows. To address this issue, three separate methods are proposed and their efficacy is demonstrated through examples. The application of RONS to neural networks is also discussed.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Marco Caliari, Fabio Cassini
Summary: In this paper, a second order exponential scheme for stiff evolutionary advection-diffusion-reaction equations is proposed. The scheme is based on a directional splitting approach and uses computation of small sized exponential-like functions and tensor-matrix products for efficient implementation. Numerical examples demonstrate the advantage of the proposed approach over state-of-the-art techniques.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Sebastiano Boscarino, Seung Yeon Cho, Giovanni Russo
Summary: This work proposes a high order conservative semi-Lagrangian method for the inhomogeneous Boltzmann equation of rarefied gas dynamics. The method combines a semi-Lagrangian scheme for the convection term, a fast spectral method for computation of the collision operator, and a high order conservative reconstruction and a weighted optimization technique to preserve conservative quantities. Numerical tests demonstrate the accuracy and efficiency of the proposed method.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)
Article
Computer Science, Interdisciplinary Applications
Jialei Li, Xiaodong Liu, Qingxiang Shi
Summary: This study shows that the number, centers, scattering strengths, inner and outer diameters of spherical shell-structured sources can be uniquely determined from the far field patterns. A numerical scheme is proposed for reconstructing the spherical shell-structured sources, which includes a migration series method for locating the centers and an iterative method for computing the inner and outer diameters without computing derivatives.
JOURNAL OF COMPUTATIONAL PHYSICS
(2024)