Computers & Fluids最新文献_第2页

GPU parallel implementation of a finite volume lattice Boltzmann method for incompressible flows 针对不可压缩流动的有限体积晶格玻尔兹曼方法的 GPU 并行执行

IF 2.5 3区工程技术

Computers & Fluids Pub Date : 2024-10-26 DOI: 10.1016/j.compfluid.2024.106460

Mengke Wen , Siyuan Shen , Weidong Li

{"title":"GPU parallel implementation of a finite volume lattice Boltzmann method for incompressible flows","authors":"Mengke Wen , Siyuan Shen , Weidong Li","doi":"10.1016/j.compfluid.2024.106460","DOIUrl":"10.1016/j.compfluid.2024.106460","url":null,"abstract":"<div><div>This work presents a graphics processing units (GPU) parallel algorithm of a cell-centered finite volume lattice Boltzmann method (FVLBM) on unstructured meshes. In the present GPU parallel algorithm, the parallelization is performed in the physical space. To reduce the frequency of GPU memory accesses, this algorithm develops coalesced access to GPU memory. In addition, to avoid the race for resources leading to data anomalies, such as dirty read or phantom read <em>etc.</em>, and the double counting for flux calculation, the efficient face-based data structure often used for flux calculation in cells in the central processing unit (CPU) version of FVLBM is modified into a face-based data structure used for the fluxes on all faces, followed by a cell-based loop for the final residuals in all cells. Therefore, the proposed GPU parallel algorithm does not need to use the resource lock and retains the high efficiency of the face-based data structure in the fluxes computation to enhance its’ parallel efficiency. Additionally, to demonstrate the computational efficiency of the proposed GPU parallel algorithm, various benchmark studies are performed in this work by the proposed parallel scheme on a double precision NVIDIA GeForce RTX 3090Ti GPU card, including (a) the lid-driven flow in a two-dimensional (2D) square cavity, (b) a 2D flow past a cylinder, and (c) the lid-driven flow in a three-dimensional (3D) cubic cavity. The numerical results show that the proposed GPU parallel algorithm can be as accurate as the original CPU serial scheme with 1 to 2 orders of speedup.</div></div>","PeriodicalId":287,"journal":{"name":"Computers & Fluids","volume":"285 ","pages":"Article 106460"},"PeriodicalIF":2.5,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Symmetry-preserving discretizations in Lagrangian cell-centered hydrodynamics 拉格朗日细胞中心流体力学中的对称保留离散化

IF 2.5 3区工程技术

Computers & Fluids Pub Date : 2024-10-24 DOI: 10.1016/j.compfluid.2024.106462

Xihua Xu

引用次数: 0

A coupled immersed boundary method and wall modelling framework for high-Reynolds number flows over complex terrain 复杂地形上高雷诺数流动的沉浸边界法与壁面建模耦合框架

IF 2.5 3区工程技术

Computers & Fluids Pub Date : 2024-10-23 DOI: 10.1016/j.compfluid.2024.106457

Jay A. Patel , Ankita Maity , Niranjan S. Ghaisas

{"title":"A coupled immersed boundary method and wall modelling framework for high-Reynolds number flows over complex terrain","authors":"Jay A. Patel , Ankita Maity , Niranjan S. Ghaisas","doi":"10.1016/j.compfluid.2024.106457","DOIUrl":"10.1016/j.compfluid.2024.106457","url":null,"abstract":"<div><div>We present the development and validation of an immersed boundary method (IBM) along with a wall model (WM) to simulate atmospheric boundary-layer flows over complex terrain. The framework presented here has two novel aspects over standard IBM implementations. First, the underlying schemes are global in nature and require specification of values throughout the solid region. Second, to enable high-Reynolds number simulations, a wall model is coupled to the IBM. The proposed numerical framework is shown to have second-order accuracy. The framework is validated by simulating flow over a 2D as well as 3D cosine-squared hill and comparing to previously published experimental results. The mean velocity and turbulence intensity are reproduced accurately by our LES. The flow over the Bolund hill, marked by steep slopes which makes this a challenging test case, is also simulated and results are compared to field observations showing good agreement. The framework also accurately reproduces the turbulent statistics in the wake of a turbine situated on a flat terrain, with the flat terrain modelled using the IBWM framework, thus demonstrating its applicability to high-Reynolds number atmospheric and wind farm flows over complex terrain.</div></div>","PeriodicalId":287,"journal":{"name":"Computers & Fluids","volume":"285 ","pages":"Article 106457"},"PeriodicalIF":2.5,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142573258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Resolving subgrid-scale structures for multiphase flows using a filament moment-of-fluid method 利用丝状流体力矩法解析多相流的亚网格尺度结构

IF 2.5 3区工程技术

Computers & Fluids Pub Date : 2024-10-22 DOI: 10.1016/j.compfluid.2024.106455

Philippe Hergibo , Timothy N. Phillips , Zhihua Xie

{"title":"Resolving subgrid-scale structures for multiphase flows using a filament moment-of-fluid method","authors":"Philippe Hergibo , Timothy N. Phillips , Zhihua Xie","doi":"10.1016/j.compfluid.2024.106455","DOIUrl":"10.1016/j.compfluid.2024.106455","url":null,"abstract":"<div><div>Multiphase flows are present in many industrial and engineering applications as well as in some physical phenomena. Capturing the interface between the phases for complex flows is challenging and requires an accurate method, especially to resolve fine-scale structures. The moment-of-fluid (MOF) method improves drastically the accuracy of interface reconstruction compared to previous geometrical methods. Instead of refining the mesh to capture increased levels of detail, the MOF method, which uses zeroth and first moments as well as a conglomeration algorithm, enables subgrid structures such as filaments to be captured at a small extra cost. Coupled to a finite volume Navier–Stokes solver, the MOF method has been tested on a fixed grid and validated using well-known benchmark problems such as dam break flows, the Rayleigh–Taylor and Kelvin–Helmholtz instability problems, and a rising bubble. The ability of the novel filament MOF method to capture the filamentary structures that eventually form for the Rayleigh–Taylor instability and rising bubble problems is assessed. Good agreement has been found with other numerical results and experimental measurements available in the literature.</div></div>","PeriodicalId":287,"journal":{"name":"Computers & Fluids","volume":"285 ","pages":"Article 106455"},"PeriodicalIF":2.5,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142528819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

An evaluation of the hybrid Fokker–Planck-DSMC approach for high-speed rarefied gas flows 高速稀薄气体流的福克-普朗克-DSMC 混合方法评估

IF 2.5 3区工程技术

Computers & Fluids Pub Date : 2024-10-22 DOI: 10.1016/j.compfluid.2024.106456

Sanghun Kim, Eunji Jun

{"title":"An evaluation of the hybrid Fokker–Planck-DSMC approach for high-speed rarefied gas flows","authors":"Sanghun Kim, Eunji Jun","doi":"10.1016/j.compfluid.2024.106456","DOIUrl":"10.1016/j.compfluid.2024.106456","url":null,"abstract":"<div><div>The Direct Simulation Monte Carlo (DSMC) method has been widely used for simulations of rarefied gas flows. It has been proven that the numerical solution of the DSMC method converges to the Boltzmann equation, providing a solid physical foundation for high Knudsen numbers. However, many aerospace engineering problems include both low and high-density regions in a single domain, making the DSMC method computationally expensive. Over the past decade, the particle Fokker–Planck (FP) method has been studied as a means to reduce computational costs near the continuum regime. While enhancing efficiency, the FP method loses physical accuracy at high Knudsen numbers. Aiming for universal accuracy and efficiency across the whole range of Knudsen numbers, the hybrid FP-DSMC method has been studied. Nevertheless, consistent comparisons among the DSMC, FP, and hybrid FP-DSMC methods have received limited attention so far. This paper presents a consistent comparative study of the DSMC, FP, and hybrid FP-DSMC methods to assess the accuracy and efficiency of the hybrid FP-DSMC method. The hybrid FP-DSMC solver is developed based on the open-source SPARTA framework. The benchmark problems include supersonic flow in a planar nozzle, hypersonic flow around a cylinder, and hypersonic flow around a THAAD-like missile. The results demonstrate that the hybrid FP-DSMC method can be more efficient than the DSMC method while being more accurate than the FP method. The speed-up achieved by the FP-DSMC method ranged from 1.5 to 14 times compared to the converged DSMC simulation.</div></div>","PeriodicalId":287,"journal":{"name":"Computers & Fluids","volume":"285 ","pages":"Article 106456"},"PeriodicalIF":2.5,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142528818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

An improved pressure gradient method for viscous incompressible flows 粘性不可压缩流的改进压力梯度法

IF 2.5 3区工程技术

Computers & Fluids Pub Date : 2024-10-22 DOI: 10.1016/j.compfluid.2024.106448

Zhisong Li , Ye Li

{"title":"An improved pressure gradient method for viscous incompressible flows","authors":"Zhisong Li , Ye Li","doi":"10.1016/j.compfluid.2024.106448","DOIUrl":"10.1016/j.compfluid.2024.106448","url":null,"abstract":"<div><div>The pressure gradient method solves the viscous incompressible flow with the pressure gradients, rather than the pressure, as unknown variables. Two variants of the pressure gradient method have been developed in the past but have not received much attention due to their unsatisfactory performance or implementation complexity. Based on the artificial compressibility concept, this study proposes an improved pressure gradient method. One distinct feature of this method is that it requires no pressure/pressure gradient boundary condition or special treatment on wall boundaries. An auxiliary variable is introduced to represent the velocity dilatation, greatly simplifying the spatial discretization and computational procedure. The mathematical formulations are elaborated and compared with the previous pressure gradient methods, followed by discussions of compatibility relationships, boundary condition setup, and an extension to a pressure Poisson-like equation. Four validation examples are performed for various flow scenarios, and the solutions and domain solenoidity are examined for each case. The study also compares associated computational methods, different pressure boundary conditions, and flow characteristics, demonstrating the benefits of the present method.</div></div>","PeriodicalId":287,"journal":{"name":"Computers & Fluids","volume":"285 ","pages":"Article 106448"},"PeriodicalIF":2.5,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142657877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Boundary conditions for SPH through energy conservation 通过能量守恒实现 SPH 的边界条件

IF 2.5 3区工程技术

Computers & Fluids Pub Date : 2024-10-18 DOI: 10.1016/j.compfluid.2024.106454

Jose Luis Cercos-Pita , Daniel Duque , Pablo Eleazar Merino-Alonso , Javier Calderon-Sanchez

引用次数: 0

Effects of two-dimensional reed oscillation on airflow and sound generation in a single-reed instrument 二维哨片振荡对单簧乐器气流和发声的影响

IF 2.5 3区工程技术

Computers & Fluids Pub Date : 2024-10-17 DOI: 10.1016/j.compfluid.2024.106452

Tsukasa Yoshinaga , Reo Baba , Hiroshi Yokoyama , Tetsuro Shoji , Akira Miki , Akiyoshi Iida

{"title":"Effects of two-dimensional reed oscillation on airflow and sound generation in a single-reed instrument","authors":"Tsukasa Yoshinaga , Reo Baba , Hiroshi Yokoyama , Tetsuro Shoji , Akira Miki , Akiyoshi Iida","doi":"10.1016/j.compfluid.2024.106452","DOIUrl":"10.1016/j.compfluid.2024.106452","url":null,"abstract":"<div><div>While two-dimensional (2D) reed oscillation modes of single-reed woodwind instruments have been reported in previous studies, little is known about their effects on airflow and sound generation. In this study, we conducted aeroacoustic simulations of a clarinet mouthpiece and resonator coupled with one-dimensional (1D) and 2D reed deformation models and investigated the changes in flow and sound generation due to the 2D reed vibration. The 1D and 2D reeds were modeled using 1D beam and thin plate theories, respectively, whereas the three-dimensional airflow was simulated by solving the compressible Navier–Stokes equations. The self-sustained oscillations of the 2D reed model mainly exhibited a flexural mode at the fundamental frequency, which is consistent with previous observations. Complex torsional modes were observed only at higher harmonic frequencies. A comparison between the 1D and 2D reed models demonstrated that the 2D reed opened later at the side face of the mouthpiece than the 1D reed owing to the torsional mode, which changed the time variation of the flow rate into the mouthpiece and the far-field sound in the high-frequency range. These results suggest the importance of the torsional deformation characteristics of reeds on the timbre of single-reed instruments.</div></div>","PeriodicalId":287,"journal":{"name":"Computers & Fluids","volume":"285 ","pages":"Article 106452"},"PeriodicalIF":2.5,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142537124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Momentum exchange method for quantum Boltzmann methods 量子波尔兹曼方法的动量交换法

IF 2.5 3区工程技术

Computers & Fluids Pub Date : 2024-10-16 DOI: 10.1016/j.compfluid.2024.106453

Merel A. Schalkers, Matthias Möller

引用次数: 0

A numerical method for simulating variable density flows in membrane desalination systems 模拟膜脱盐系统中变密度流动的数值方法

IF 2.5 3区工程技术

Computers & Fluids Pub Date : 2024-10-11 DOI: 10.1016/j.compfluid.2024.106449

Federico Municchi , Yiming Liu , Jingbo Wang , Tzahi Y. Cath , Craig S. Turchi , Michael B. Heeley , Eric M.V. Hoek , David Jassby , Nils Tilton

{"title":"A numerical method for simulating variable density flows in membrane desalination systems","authors":"Federico Municchi , Yiming Liu , Jingbo Wang , Tzahi Y. Cath , Craig S. Turchi , Michael B. Heeley , Eric M.V. Hoek , David Jassby , Nils Tilton","doi":"10.1016/j.compfluid.2024.106449","DOIUrl":"10.1016/j.compfluid.2024.106449","url":null,"abstract":"<div><div>We present a novel method for simulating unsteady, variable density, fluid flows in membrane desalination systems. By assuming the density varies only with concentration and temperature, the scheme decouples the solution of the governing equations into two sequential blocks. The first solves the governing equations for the temperature and concentration fields, which are used to compute all thermophysical properties. The second block solves the conservation of mass and momentum equations for the velocity and pressure. We show that this is computationally more efficient than schemes that iterate over the full coupled equations in one block. We verify that the method achieves second-order spatial–temporal accuracy, and we use the method to investigate buoyancy-driven convection in a desalination process called vacuum membrane distillation. Specifically, we show that with gravity properly oriented, variations in temperature and concentration can trigger a double-diffusive instability that enhances mixing and improves water recovery. We also show that the instability can be strengthened by providing external heating.</div></div>","PeriodicalId":287,"journal":{"name":"Computers & Fluids","volume":"285 ","pages":"Article 106449"},"PeriodicalIF":2.5,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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