Computers & Fluids最新文献_第7页

Development and assessment of an improved Baldwin-Lomax turbulence model for complex hypersonic flows in two and three dimensions 二维和三维复杂高超声速流动改进Baldwin-Lomax湍流模型的发展和评估

IF 3 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2026-01-30 Epub Date: 2025-11-15 DOI: 10.1016/j.compfluid.2025.106917

Jian Shen , Xianliang Chen , Lin Fu

Accurate prediction of hypersonic turbulent boundary layers is critical for the design of hypersonic vehicles. Traditional turbulence models were originally developed for incompressible flows and are commonly extended to compressible conditions by employing density-weighted averages. In a recent study, Chen et al. (J. Fluid Mech., 2024, vol 987, A7) proposed an improved Baldwin-Lomax (BL) turbulence model by incorporating velocity transformations and the temperature-velocity relation. Their modifications yielded notable improvements for high-speed zero-pressure-gradient flat-plate flows. Building upon this foundation, the present study introduces further enhancements to Chen et al.’s BL model to improve its accuracy and robustness for complex hypersonic configurations. The improved BL turbulence model is implemented into a standard computational fluid dynamics (CFD) solver and validated against direct numerical simulation results and experimental data across two- and three-dimensional hypersonic cases involving pressure gradients, cold walls, and shock/boundary-layer interactions. The results show that the improved BL turbulence model generally achieves superior accuracy in attached flow regions compared to the baseline BL, Spalart-Allmaras and k–ω SST turbulence models. These findings highlight the model’s potential for practical use in hypersonic flow simulations, offering a valuable tool for aerospace engineering applications.

高超声速湍流边界层的准确预测对高超声速飞行器的设计至关重要。传统的湍流模型最初是为不可压缩流动开发的，通常通过使用密度加权平均来扩展到可压缩条件。在最近的一项研究中，Chen等(J.流体力学。湍流模型（Baldwin-Lomax， BL）是一种基于速度变换和温度-速度关系的湍流模型。他们的改进对高速零压力梯度平板流产生了显著的改善。在此基础上，本研究对Chen等人的BL模型进行了进一步的改进，以提高其对复杂高超声速构型的精度和鲁棒性。将改进的BL湍流模型实现到标准计算流体动力学（CFD）求解器中，并通过直接数值模拟结果和实验数据验证了涉及压力梯度、冷壁和激波/边界层相互作用的二维和三维高超声速情况。结果表明，与基线BL、Spalart-Allmaras和k -ω海表温度湍流模型相比，改进的BL湍流模型在附加流区总体上具有更高的精度。这些发现突出了该模型在高超声速流动模拟中的实际应用潜力，为航空航天工程应用提供了有价值的工具。

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引用次数: 0

Implicit-PointSAGE: Neural implicit representation based superresolution for computational fluid dynamics 隐式点：基于神经隐式表示的计算流体动力学超分辨率

IF 3 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2026-01-30 Epub Date: 2025-11-08 DOI: 10.1016/j.compfluid.2025.106900

Rajat Kumar Sarkar , Vishal Jadhav , Venkataramana Runkana

High-resolution computational fluid dynamics (CFD) simulations are essential for capturing complex fluid flow phenomena such as turbulent flows and shock-boundary layer interactions that are critical for aerospace applications. However, the high computational cost of obtaining simulation results at high resolution often limits their practicality. Traditional deep learning-based super-resolution methods such as UNets have been explored to predict fine-mesh simulation results from coarse-mesh simulations, but they face challenges with unstructured meshes and require extensive amounts of training data. To address these limitations, we propose Implicit-PointSAGE, a mesh-independent super-resolution framework that leverages unordered, mesh-less structure of point clouds to simulate intricate fluid dynamics. By integrating the strengths of PointSAGE with a Neural Implicit Learning module employing Galerkin-based attention, the framework efficiently captures the underlying physics and accurately predicts fine-mesh data directly from coarse-mesh inputs. Implicit-PointSAGE demonstrates significant computational efficiency, scalability to diverse point cloud sizes, and adaptability across various CFD scenarios. It matches the performance of state-of-the-art surrogate models in solving problems represented by PDEs, achieving high accuracy with 10 to 100 times fewer data samples-sometimes requiring as few as 100 samples-while delivering substantial computational acceleration. These results position Implicit-PointSAGE as a transformative tool for super-resolution modeling and efficient high-resolution CFD simulations.

高分辨率计算流体动力学（CFD）模拟对于捕捉复杂的流体流动现象（如湍流和激波边界层相互作用）至关重要，这对航空航天应用至关重要。然而，获得高分辨率模拟结果的计算成本高，往往限制了其实用性。传统的基于深度学习的超分辨率方法（如UNets）已经被用于从粗网格模拟中预测细网格模拟结果，但它们面临着非结构化网格的挑战，并且需要大量的训练数据。为了解决这些限制，我们提出了Implicit-PointSAGE，这是一个网格无关的超分辨率框架，利用点云的无序，无网格结构来模拟复杂的流体动力学。通过将PointSAGE的优势与基于galerkin注意力的神经内隐学习模块相结合，该框架有效地捕获底层物理，并直接从粗网格输入中准确预测细网格数据。Implicit-PointSAGE展示了显著的计算效率，不同点云大小的可扩展性，以及各种CFD场景的适应性。在解决由pde表示的问题时，它与最先进的代理模型的性能相匹配，用10到100倍的数据样本（有时只需要100个样本）实现高精度，同时提供大量的计算加速。这些结果使Implicit-PointSAGE成为超分辨率建模和高效高分辨率CFD模拟的变革性工具。

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引用次数: 0

Mimetic differences and pseudo symplectic Runge Kutta methods for incompressible Navier Stokes equations 不可压缩Navier Stokes方程的模拟差分和伪辛Runge Kutta方法

IF 3 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2026-01-30 Epub Date: 2025-11-11 DOI: 10.1016/j.compfluid.2025.106898

Anand Srinivasan , Perry Johnson , José Castillo

The control of aliasing errors arising from the non-linear convective terms in the incompressible Navier Stokes equation requires care when investigating turbulent flow regimes. Discretization schemes that fail to mirror the conservation properties such as global kinetic energy (which is inherent to the continuum form) can result in spurious numerical energy build-up for turbulent flow simulations. Mimetic difference methods that operate on a staggered grid satisfy a discrete version of the continuum conservation laws, thereby resulting in more accurate numerical simulations. The high order mimetic operators of Corbino-Castillo using a skew-symmetric formulation is considered in the present work. On the temporal side, pseudo symplectic methods are investigated to obtain global kinetic energy preserving numerical solutions of the NS equations in turbulent flow regimes. Numerical examples highlighting the implementation of the mimetic pseudo symplectic schemes are also presented.

不可压缩的Navier Stokes方程中非线性对流项引起的混叠误差的控制在研究湍流型时需要注意。如果离散化方案不能反映全局动能（这是连续体形式固有的）等守恒特性，则可能导致湍流模拟中虚假的数值能量积累。在交错网格上运行的模拟差分方法满足连续介质守恒定律的离散版本，从而产生更精确的数值模拟。本文研究了利用偏对称公式的高阶模拟算子Corbino-Castillo。在时间方面，研究了伪辛方法，以获得湍流状态下NS方程的全局保动能数值解。文中还给出了仿真伪辛格式的具体实现实例。

引用次数: 0

Adaptive criterion and modification of wave-particle decomposition in UGKWP method for high-speed flow simulation 高速流动模拟UGKWP法波粒分解自适应准则及修正

IF 3 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2026-01-30 Epub Date: 2025-11-06 DOI: 10.1016/j.compfluid.2025.106896

Junzhe Cao , Yufeng Wei , Wenpei Long , Chengwen Zhong , Kun Xu

Benefiting from its direct modeling of physical laws in discretized space and its automatic decomposition of hydrodynamic waves and particles, the unified gas-kinetic wave-particle (UGKWP) method provides significant advantages for a wide range of multiscale physical problems, including hypersonic flow, plasma transport, and radiation transport. To achieve a more effective and efficient wave-particle decomposition in high-speed flow simulations, particularly in regions with drastic scale variations, this work investigates a scale-adaptive criterion and introduces modifications to the flux evolution of the UGKWP method. In addition to the intrinsic time-based criterion embedded in the time-dependent distribution function of UGKWP, two further criteria-based on spatial resolution and local gradients–are employed to identify the local scale and reduce the computational overhead of particles in representing near-equilibrium gas distributions. Furthermore, by aligning the evolution of hydrodynamic waves with the coefficients in the time–integration flux of the unified gas-kinetic scheme (UGKS), the modified wave representation improves consistency with particle contributions, which is especially critical when flow scales vary significantly across computational cells. The effectiveness of the adaptive UGKWP method is demonstrated through a series of benchmark cases, including hypersonic flows around a cylinder at various inflow Knudsen numbers, hypersonic flow over a slender cavity, side-jet impingement in hypersonic flow, and three-dimensional hypersonic flows over a 70^∘ blunted cone with a cylindrical sting.

统一气动波粒（UGKWP）方法直接模拟离散空间中的物理规律，并能自动分解流体动力波粒，为高超声速流动、等离子体输运、辐射输运等广泛的多尺度物理问题提供了显著的优势。为了在高速流动模拟中实现更有效的波粒分解，特别是在尺度变化较大的地区，本文研究了一种尺度自适应准则，并对UGKWP方法的通量演化进行了修改。除了嵌入UGKWP时变分布函数中的固有时变准则外，还采用了基于空间分辨率和局部梯度的两个准则来识别局部尺度，并减少了粒子在表示近平衡气体分布时的计算开销。此外，通过将水动力波的演变与统一气体动力学格式（UGKS）的时间积分通量系数对齐，改进的波表示提高了与颗粒贡献的一致性，这在不同计算单元之间的流动尺度差异很大时尤为重要。自适应UGKWP方法的有效性通过一系列基准案例得到了证明，这些案例包括以不同努森数流入的高超声速绕圆柱体流动、在细长腔体上的高超声速流动、高超声速流动中的侧向射流撞击，以及在70°钝化圆锥体上的三维高超声速流动。

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引用次数: 0

Direct Poisson solver combining domain decomposition and influence matrix methods and its application to DNS of oscillating grid turbulence 结合域分解和影响矩阵法的直接泊松求解方法及其在振荡网格湍流DNS中的应用

IF 3 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2026-01-30 Epub Date: 2025-10-31 DOI: 10.1016/j.compfluid.2025.106891

Toru Yamada , Ryuga Sumi , Yohei Morinishi

This study presents the application of a direct Poisson solver combining domain decomposition and influence matrix methods to the direct numerical simulation (DNS) of oscillating grid turbulence (OGT). Solving the pressure Poisson equation is one of the major challenges in computational fluid dynamics. Traditional direct methods are accurate but difficult to be applied to large-scale problems, while iterative methods can suffer from slow convergence. The hybrid approach enables the use of the direct methods for the problem with complex computational geometry. The results show that this direct solver significantly reduces computation time compared to the iterative BiCGSTAB method. The DNS results are validated by comparison of experimental data, demonstrating good agreement in the vertical distribution of velocity fluctuation intensity. Therefore, the efficiency of this direct method for simulating the OGT turbulent flows is confirmed.

本文提出了结合域分解和影响矩阵法的直接泊松求解方法在振荡网格湍流直接数值模拟中的应用。求解压力泊松方程是计算流体力学的主要挑战之一。传统的直接法精度高，但难以应用于大规模问题，迭代法收敛速度慢。这种混合方法使直接求解复杂计算几何问题成为可能。结果表明，与迭代的BiCGSTAB方法相比，该直接求解器显著减少了计算时间。通过与实验数据的对比，验证了DNS计算结果的正确性，表明速度波动强度的垂直分布具有较好的一致性。从而验证了该直接方法模拟OGT湍流的有效性。

引用次数: 0

A solver-agnostic Lagrangian approach for efficient particle tracking in unsteady multiphase flows 非定常多相流中有效粒子跟踪的求解器不可知拉格朗日方法

IF 3 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2026-01-30 Epub Date: 2025-11-11 DOI: 10.1016/j.compfluid.2025.106914

Yimeng Du , Zhendong Jin , Chengjun Zhang , Yan Cui , Yulong Wang , Rongxuan Hu , Peng Gao , Martin Sommerfeld

This work introduces a novel one-way coupled Lagrangian Particle Tracking (LPT) approach that demonstrates strong compatibility with various fluid solvers, enabling efficient particle tracking in unsteady flows. By utilizing the standard Visualization Toolkit (VTK) format, this method efficiently manages data by loading sampled instantaneous flow data, significantly reducing computational costs while tracking multiple particle properties. Crucially, this decoupling from fluid solvers allows researchers to rapidly prototype and validate new LPT models without rerunning the underlying CFD simulations, thereby dramatically accelerating iterative model development. Consequently, the method requires that the time interval be sufficiently fine to capture key flow characteristics, while the total time span covers the complete evolutionary process of the flow. Extensive numerical validations confirm its accuracy and versatility across diverse flow scenarios, including Couette and Poiseuille flows, lid-driven cavity flow, backward-facing step flow, and 90° duct bend flow. Its effectiveness in pharmaceutical aerosol applications—encompassing respiratory and dry-powder inhalers—further highlights its scalability and physical fidelity. The approach's flexibility supports the integration of complex physical models and offers a user-friendly interface through the open-source software ParaView®. This innovation not only addresses challenges faced by engineers using commercial Computational Fluid Dynamics (CFD) software but also transforms the research workflow by enabling agile exploration of particle physics, thus expediting discovery timelines in multiphase flow studies.

这项工作介绍了一种新的单向耦合拉格朗日粒子跟踪（LPT）方法，该方法与各种流体求解器具有很强的兼容性，可以在非定常流动中实现有效的粒子跟踪。通过使用标准的可视化工具包（VTK）格式，该方法通过加载采样的瞬时流数据来有效地管理数据，在跟踪多个粒子属性时显著降低了计算成本。至关重要的是，这种与流体求解器的解耦使研究人员能够快速构建和验证新的LPT模型，而无需重新运行底层CFD模拟，从而大大加快了迭代模型的开发。因此，该方法要求时间间隔足够细，以捕捉关键的流动特征，而总时间跨度涵盖了流动的完整演化过程。大量的数值验证证实了其在不同流动场景下的准确性和通用性，包括Couette和Poiseuille流动、盖子驱动的腔体流动、向后台阶流动和90°管道弯曲流动。它在医药气溶胶应用中的有效性——包括呼吸和干粉吸入器——进一步突出了它的可扩展性和物理保真度。该方法的灵活性支持复杂物理模型的集成，并通过开源软件ParaView®提供用户友好的界面。这一创新不仅解决了工程师使用商业计算流体动力学（CFD）软件所面临的挑战，而且通过实现对粒子物理的敏捷探索，改变了研究工作流程，从而加快了多相流研究的发现时间。

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引用次数: 0

Embedded strong stability preserving Runge-Kutta methods with adaptive time stepping for shock-dominated flows 基于自适应时间步进的冲击控制流嵌入强保稳定龙格-库塔方法

IF 3 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2026-01-30 Epub Date: 2025-11-15 DOI: 10.1016/j.compfluid.2025.106916

Francesco Mario D’Afiero

Accurate time integration of hyperbolic-parabolic systems, particularly in the presence of shocks and steep gradients, remains a central challenge in computational fluid dynamics. In this work, we propose a robust, adaptive time integration framework for discontinuous Galerkin discretizations that combines an embedded third-order Strong Stability Preserving Runge-Kutta method with physics-based shock capturing and novel error control strategies. The proposed method is based on total variation diminishing properties while leveraging a proportional-integral controller for adaptive step-size selection, eliminating the need for empirical CFL tuning. A key innovation lies in the introduction of an entropy-based filtering mechanism that modulates element-wise error estimates, effectively dampening spurious spikes induced by discontinuities. Additionally, the integral term of the PI controller is stabilized using a moving median over a sliding window, enhancing reliability in shock-dominated regimes. The overall methodology requires no parameter tuning beyond a user-defined error tolerance (as it is common in any ordinary differential equation) and is demonstrated to be stable and accurate across a broad range of canonical test cases. Compared to conventional CFL stable solution obtained for the same numerical setups in a previous work, the proposed approach consistently delivers improved accuracy and robustness for high-fidelity simulations in complex compressible flows.

双曲抛物系统的精确时间积分，特别是在存在冲击和陡峭梯度的情况下，仍然是计算流体动力学的核心挑战。在这项工作中，我们提出了一个用于不连续伽辽金离散化的鲁棒自适应时间积分框架，该框架将嵌入式三阶强稳定保持龙格-库塔方法与基于物理的冲击捕获和新的误差控制策略相结合。该方法基于总变差递减特性，同时利用比例积分控制器进行自适应步长选择，消除了经验CFL调谐的需要。一个关键的创新在于引入了一种基于熵的过滤机制，该机制可以调节元素的误差估计，有效地抑制由不连续引起的虚假峰值。此外，PI控制器的积分项使用滑动窗口上的移动中值来稳定，提高了在冲击主导状态下的可靠性。整个方法不需要超出用户定义的容错范围的参数调优（因为这在任何常微分方程中都很常见），并且在广泛的规范测试用例中被证明是稳定和准确的。与之前在相同数值设置下获得的传统CFL稳定解相比，该方法在复杂可压缩流动的高保真模拟中始终提供更高的准确性和鲁棒性。

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引用次数: 0

Grid resolution requirements for DNS of shock/boundary-layer interactions 激波/边界层相互作用DNS的网格分辨率要求

IF 3 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2026-01-30 Epub Date: 2025-11-04 DOI: 10.1016/j.compfluid.2025.106892

Alessandro Ceci , Andrea Palumbo , Sergio Pirozzoli

Direct Numerical Simulation (DNS) of shock-boundary-layer interactions (SBLI) is critical for accurate prediction of turbulence, heat transfer, and separation in high-speed flows. One of the main challenges is selecting a grid resolution that properly resolves both pre- and post-interaction states while maintaining computational efficiency. This study systematically examines the impact of grid resolution on DNS accuracy, with particular focus on the post-interaction region, where turbulence length scales undergo a dramatic reduction-especially under hypersonic flow conditions. Through a series of high-fidelity simulations using grids of increasing resolution, we quantify the consequences of under-resolution on turbulence statistics, skin friction, and heat transfer, and demonstrate that classical DNS criteria remain applicable in SBLI once the viscous length scale reduction across the shock is properly accounted for. To support mesh design, we propose and validate a simple predictive scaling law, based solely on inviscid flow quantities, that estimates this reduction and thus enables a priori resolution requirements to be determined across different configurations. These results go beyond confirming the need for fine grids, providing a predictive tool to guide future DNS and wall-modeled LES of hypersonic SBLI.

激波边界层相互作用（SBLI）的直接数值模拟（DNS）对于准确预测高速流动中的湍流、传热和分离至关重要。其中一个主要的挑战是选择一种网格分辨率，在保持计算效率的同时，适当地解决前交互和后交互状态。本研究系统地考察了网格分辨率对DNS精度的影响，特别关注了相互作用后区域，其中湍流长度尺度经历了显着减少-特别是在高超声速流动条件下。通过一系列使用增加分辨率网格的高保真度模拟，我们量化了分辨率不足对湍流统计、表面摩擦和传热的影响，并证明了经典的DNS标准在SBLI中仍然适用，一旦在激波上的粘性长度尺度减小得到了适当的考虑。为了支持网格设计，我们提出并验证了一个简单的预测缩放定律，该定律仅基于无粘流量，可以估计这种减少，从而可以在不同的配置中确定先验的分辨率要求。这些结果不仅证实了对精细网格的需求，还为指导未来高超声速SBLI的DNS和壁面建模LES提供了预测工具。

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引用次数: 0

High order global flux schemes for general steady state preservation of shallow water moment equations with non-conservative products 具有非保守积的浅水力矩方程一般稳态保持的高阶全局通量格式

IF 3 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2026-01-30 Epub Date: 2025-10-30 DOI: 10.1016/j.compfluid.2025.106887

Mirco Ciallella , Julian Koellermeier

Shallow water moment equations are reduced-order models for free-surface flows that allow to represent vertical variations of the velocity profile at the expense of additional evolution equations for a number of additional variables, so called moments. This introduces non-linear non-conservative products in the system, which make the analytical characterization of steady states much harder if not impossible. The lack of analytical steady states poses a challenge for the design of well-balanced schemes, which aim at preserving such steady states as crucial in many applications.

In this work, we present a family of fully approximately well-balanced, high-order WENO finite volume methods for general hyperbolic balance laws with non-conservative products like the shallow water moment equations, for which no analytical steady states are available. The schemes are based on the flux globalization approach, in which both source terms and non-conservative products are integrated with a tailored high order quadrature in the divergence term. The resulting global flux is then reconstructed instead of the conservative variables to preserve all steady states. Numerical tests show the optimal convergence of the method and a significant error reduction for steady state solutions. Furthermore, we provide a numerical comparison of perturbed steady states for different families of shallow water moment equations, which illustrates the flexibility of our method that is valid for general equations without prior knowledge of steady states.

浅水力矩方程是自由水面流动的降阶模型，它可以表示速度剖面的垂直变化，但要牺牲一些附加变量的附加演化方程，即所谓的力矩。这在系统中引入了非线性非保守积，这使得稳态的分析表征更加困难，如果不是不可能的话。分析稳态的缺乏对平衡方案的设计提出了挑战，平衡方案旨在保持在许多应用中至关重要的稳定状态。在这项工作中，我们提出了一组完全近似良好平衡的高阶WENO有限体积方法，用于一般双曲平衡律的非保守乘积，如浅水力矩方程，其中没有可用的解析稳态。该方案基于通量全球化方法，其中源项和非保守积都与散度项中的定制高阶正交相结合。然后重建得到的全局通量，而不是保守变量，以保持所有稳态。数值试验表明，该方法具有最优的收敛性，并显著减小了稳态解的误差。此外，我们提供了不同类型的浅水力矩方程的扰动稳态的数值比较，这说明了我们的方法的灵活性，适用于没有稳态先验知识的一般方程。

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引用次数: 0

GPU accelerated vortex-induced vibration simulation using JAX: Efficiency and accuracy strategies 基于JAX的GPU加速涡激振动仿真：效率与精度策略

IF 3 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2026-01-30 Epub Date: 2025-11-13 DOI: 10.1016/j.compfluid.2025.106913

Haiming Zhu , Yuan Yang , Zunfeng Du , Jianxing Yu

This study presents an immersed boundary-lattice Boltzmann method (IB-LBM) simulation framework for vortex-induced vibration (VIV), implemented using the JAX framework to exploit GPU acceleration. The code is specifically structured to meet JAX’s functional and static requirements, incorporating an efficient multi-block grid refinement scheme and a novel dynamic region approach for immersed boundary calculations. Through systematic benchmarking and convergence studies, we revealed that the present dynamic region approach achieves improved efficiency by reducing computational workload while avoiding excessive dynamic array operations. We demonstrated that the grid refinement setting should be adjusted according to the Reynolds number to maintain accuracy. The results also showed that while grid refinement saves total time-to-solution, parallel efficiency is reduced due to the stalls caused by frequent inter-block communications. Furthermore, we compared fluid-structure coupling strategies, finding that while weak coupling is adequate for amplitude prediction, strong coupling with at least two iterations is necessary to eliminate spurious frequency artifacts in the response. These findings offer practical guidelines for achieving efficient and accurate VIV simulations with IB-LBM on modern GPU platforms.

本研究提出了一种浸入式边界晶格玻尔兹曼方法（IB-LBM）涡激振动（VIV）仿真框架，该框架使用JAX框架实现，以利用GPU加速。该代码的结构专门满足JAX的功能和静态要求，结合了高效的多块网格细化方案和用于浸入边界计算的新型动态区域方法。通过系统的基准测试和收敛性研究，我们发现当前的动态区域方法在减少计算工作量的同时避免了过多的动态阵列操作，从而提高了效率。我们证明，网格细化设置应根据雷诺数调整，以保持精度。结果还表明，虽然网格细化节省了总求解时间，但由于频繁的块间通信造成的延迟，并行效率降低。此外，我们比较了流固耦合策略，发现弱耦合足以用于振幅预测，而至少两次迭代的强耦合则需要消除响应中的杂散频率伪像。这些发现为在现代GPU平台上使用IB-LBM实现高效准确的VIV模拟提供了实用指南。

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引用次数: 0