Theoretical and Computational Fluid Dynamics最新文献

Wavelet-based adaptive implicit LES/under-resolved DNS of forced isotropic turbulence 基于小波的强迫各向同性湍流自适应隐式LES/欠分辨DNS

IF 2.8 3区工程技术

Theoretical and Computational Fluid Dynamics Pub Date : 2025-09-29 DOI: 10.1007/s00162-025-00762-0

Giuliano De Stefano

引用次数: 0

Special Issue: data-driven and physics-based modelling of coherent structures in turbulent shear flow 特刊：湍流剪切流中相干结构的数据驱动和基于物理的建模

IF 2.8 3区工程技术

Theoretical and Computational Fluid Dynamics Pub Date : 2025-09-20 DOI: 10.1007/s00162-025-00759-9

Kilian Oberleithner, André Cavalieri, Vassili Kitsios

引用次数: 0

Mach Independence of Entropy Layer Instabilities 熵层不稳定性的马赫独立性

IF 2.8 3区工程技术

Theoretical and Computational Fluid Dynamics Pub Date : 2025-09-17 DOI: 10.1007/s00162-025-00758-w

Iliya Milman, Michael Karp

引用次数: 0

Localised proper orthogonal decomposition 局部固有正交分解

IF 2.8 3区工程技术

Theoretical and Computational Fluid Dynamics Pub Date : 2025-09-17 DOI: 10.1007/s00162-025-00760-2

Dyhia Elhaddad, Igor Maingonnat, Gilles Tissot, Noé Lahaye

{"title":"Localised proper orthogonal decomposition","authors":"Dyhia Elhaddad, Igor Maingonnat, Gilles Tissot, Noé Lahaye","doi":"10.1007/s00162-025-00760-2","DOIUrl":"10.1007/s00162-025-00760-2","url":null,"abstract":"<div><p>Proper Orthogonal Decomposition (POD) extracts an optimal orthonormal basis for reconstructing a sequence of data. This technique is widely used in fluid mechanics to construct reduced-order models for physical analysis, modelling, estimation, and control. However, when the number of snapshots is small and the spatial domain is large, convergence of the basis with respect to the number of samples is compromised. This often results in a degradation of the quality of the resulting reduced-order models. In this study, we propose a localisation procedure to mitigate convergence artefacts in the context of limited data. Specifically, we adapt Schur product-based localisation – commonly used in operational data assimilation – to the POD framework. We develop an algorithm that operates directly on the snapshots rather than on the large-scale correlation tensor. In addition, we introduce a family of partition-of-unity localisation functions to preserve the reconstruction properties of the localised POD basis. By artificially increasing the rank of the correlation tensor, we demonstrate that the localised POD, computed from a limited number of snapshots, can approximate the POD basis obtained from a larger dataset. This is illustrated using a wave field scattered by a turbulent jet in a rotating shallow water system. We further show that using smooth, overlapping localisation functions enables physically meaningful reconstructions. The reconstruction capabilities of the method are also demonstrated using a realistic internal wave field in the Gulf Stream region, based on a high-resolution numerical simulation.</p></div>","PeriodicalId":795,"journal":{"name":"Theoretical and Computational Fluid Dynamics","volume":"39 5","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145073955","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 efficient and highly scalable solver for modelling thin film flows in heterogeneous environments 一个高效和高度可扩展的求解器，用于模拟薄膜在异质环境中的流动

IF 2.8 3区工程技术

Theoretical and Computational Fluid Dynamics Pub Date : 2025-09-13 DOI: 10.1007/s00162-025-00757-x

Panayiotis Yiannis Vrionis, Andreas D. Demou, George Karapetsas, Demetrios T. Papageorgiou, Nikos Savva

引用次数: 0

Analysis of Newtonian fluid flows around sharp corners with slip boundary conditions 具有滑移边界条件的陡角处牛顿流体流动分析

IF 2.8 3区工程技术

Theoretical and Computational Fluid Dynamics Pub Date : 2025-09-13 DOI: 10.1007/s00162-025-00756-y

J. D. Evans, I. L. Palhares Junior, C. M. Oishi, F. Ruano Neto

{"title":"Analysis of Newtonian fluid flows around sharp corners with slip boundary conditions","authors":"J. D. Evans, I. L. Palhares Junior, C. M. Oishi, F. Ruano Neto","doi":"10.1007/s00162-025-00756-y","DOIUrl":"10.1007/s00162-025-00756-y","url":null,"abstract":"<div><p>This study examines the asymptotic and numerical behaviour of Newtonian fluid flows in geometries with sharp corners and the influence of the Navier slip boundary condition. A new similarity solution for a reentrant corner flow is derived by introducing a modification to the classical Navier slip law, where the slip coefficient is modelled as a function of the radial distance along the walls from the reentrant corner. This spatially dependent slip coefficient interpolates between the well-known no-slip similarity solution and the constant slip coefficient case in which the walls behave locally as free surfaces. The stress and pressure singularities now depend on the slip coefficient and the similarity solution is validated numerically through flow simulations in an L-shaped domain. This modified slip coefficient is then used to numerically investigate the influence of the corner stress singularity on the global flow behaviours of two benchmark problems: the 4:1 planar contraction flow and the 1:4 planar expansion flow. Specifically, its effect on salient vortex size and intensity, Couette correction and the flow type (extensional, shear or rotation). This combined asymptotic and numerical framework provides new insights into the role of boundary conditions in controlling flow behaviour near singular geometries, which has not previously been investigated.</p></div>","PeriodicalId":795,"journal":{"name":"Theoretical and Computational Fluid Dynamics","volume":"39 5","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145050827","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

Regularized Gaussian 11-moment equations for polyatomic gases: Derivation, linear analysis, and its applications 多原子气体的正则化高斯11矩方程：推导，线性分析及其应用

IF 2.8 3区工程技术

Theoretical and Computational Fluid Dynamics Pub Date : 2025-09-08 DOI: 10.1007/s00162-025-00755-z

Anil Kumar, Masrakain Ahmad, Anirudh Singh Rana

{"title":"Regularized Gaussian 11-moment equations for polyatomic gases: Derivation, linear analysis, and its applications","authors":"Anil Kumar, Masrakain Ahmad, Anirudh Singh Rana","doi":"10.1007/s00162-025-00755-z","DOIUrl":"10.1007/s00162-025-00755-z","url":null,"abstract":"<div><p>This article presents a macroscopic closure for rarefied polyatomic gas flows, focusing on a regularized Gaussian 11-moment (RG11) system. Our model uses a generalized Gaussian distribution-a product of Gaussian and Gamma functions-to capture both translational and internal energies of polyatomic molecules. The closure is achieved through a regularization technique, following Struchtrup & Torrilhon (Physics of Fluids, vol. 15, 2003) approach for R13 equations in monatomic gases. In addition, we use a Bhatnagar-Gross-Krook (BGK)-type relaxation model to evaluate the production terms in the moment equations. The proposed model incorporates three relaxation parameters, which can be tuned to match viscosity, bulk viscosity, and thermal conductivity accurately for the gas under consideration. By applying a Chapman-Enskog-like expansion and an order-of-magnitude analysis, we derive the RG11 equations, featuring non-zero constitutive relations for both internal and translational heat flux. This new formulation is linearly stable in one-dimensional case across all wavelengths and frequencies, aligns well with experimental data for sound wave propagation, and agrees with validated hydrodynamic theories that are known to match experimental results for Rayleigh-Brillouin scattering (RBS), outperforming the Navier-Stokes-Fourier (NSF) equations.</p></div>","PeriodicalId":795,"journal":{"name":"Theoretical and Computational Fluid Dynamics","volume":"39 5","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145011846","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

Implicit immersed boundary method integrated into the Vanka ‘big box’ smoother. 隐式浸入边界法集成到Vanka“大盒子”光滑中。

IF 2.8 3区工程技术

Theoretical and Computational Fluid Dynamics Pub Date : 2025-09-08 DOI: 10.1007/s00162-025-00754-0

Kirill Goncharuk, Mukesh Kumar, Oz Oshri, Yuri Feldman

{"title":"Implicit immersed boundary method integrated into the Vanka ‘big box’ smoother.","authors":"Kirill Goncharuk, Mukesh Kumar, Oz Oshri, Yuri Feldman","doi":"10.1007/s00162-025-00754-0","DOIUrl":"10.1007/s00162-025-00754-0","url":null,"abstract":"<div><p>The current study introduces a novel fully coupled monolithic solver for the direct forcing immersed boundary method (IBM) in incompressible flows. The solver simultaneously integrates pressure, velocity, nonlinear convection terms, and Lagrangian forces into a unified framework, leveraging a modified big-box Vanka smoother extended with additional Lagrange multipliers arising from the IBM formulation. Central to the approach is the use of a Schur complement decomposition, which reduces the operator size by two-thirds while preserving both stability and accuracy. The solver’s monolithic structure eliminates splitting errors and artificial pressure boundary conditions, common drawbacks of segregated methods. Additionally, the developed methodology enables high CFL numbers (up to 0.5), making it particularly effective for moving boundary simulations. Verification studies cover a broad set of benchmark problems, including both stationary and moving immersed bodies across a wide range of Reynolds numbers. These tests confirm that the solver achieves computational times comparable to existing semi-implicit methods while enhancing accuracy and stability. By addressing key challenges in high-fidelity incompressible flow simulations, the proposed method offers a robust and broadly applicable monolithic solver.</p></div>","PeriodicalId":795,"journal":{"name":"Theoretical and Computational Fluid Dynamics","volume":"39 5","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00162-025-00754-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145011845","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

Peristaltic Eyring-Powell Nanofluid Flow Linking with Microorganisms across a Curved Channel 蠕动埃林-鲍威尔纳米流体流动与微生物通过弯曲通道连接

IF 2.8 3区工程技术

Theoretical and Computational Fluid Dynamics Pub Date : 2025-08-29 DOI: 10.1007/s00162-025-00751-3

Mona A. A. Mohamed

{"title":"Peristaltic Eyring-Powell Nanofluid Flow Linking with Microorganisms across a Curved Channel","authors":"Mona A. A. Mohamed","doi":"10.1007/s00162-025-00751-3","DOIUrl":"10.1007/s00162-025-00751-3","url":null,"abstract":"<div><p>The study of peristaltic Eyring-Powell nanofluid (EPF) with microorganisms is crucial in biomedical and industrial processes, improving drug delivery systems, bioreactors, and targeted microorganism transport. The EPF in a curved peristaltic channel under the influence of a uniform normal magnetic field (MF) and inside a permeable material is therefore considered in the current issue. The flow also comprises microorganisms and is motivated by the effects of porous media, Joule heating, non-Newtonian dissipation, and chemical reactions. The current work innovation stems from the inclusion of nanoparticles and microorganisms through non-Newtonian fluid flows in a curved channel, utilizing the curvilinear coordinates, which have several implications in engineering, industry, and biology. The flow under contemplation is caused by peristaltic waves that have a constant wavelength and amplitude. The problem’s governing equations are modeled using curvilinear coordinates. The goal is to maintain simplicity, and subsequently, so the problem is illustrated in the wave frame instead of the fixed frame. Under low Reynolds number and long wavelength approximation in the wave frame of reference, the mathematical framework addresses energy, momentum, nanomaterial’s volume fraction, and microbe concentration together with appropriate boundary conditions (BCs). The solutions of the governing system are handled with the help of shooting criteria and an appropriate numerical implicit method via the fourth-order Runge-Kutta (RK-4). The physical outcomes concerning flow parameters are presented to indicate the enhancement and decay factors of all relevant distributions, together with the heat and mass transfer coefficients. It is found that the factors that enhance the existence of nanoparticles and heat broadcast are the same that decay the presence of microbes, which gives practical importance to the current issue.</p></div>","PeriodicalId":795,"journal":{"name":"Theoretical and Computational Fluid Dynamics","volume":"39 5","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00162-025-00751-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144914834","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

Channel Flow with an Ice Constriction: Direct Simulation and Reduced-System Analysis 冰收缩的河道流动：直接模拟和简化系统分析

IF 2.8 3区工程技术

Theoretical and Computational Fluid Dynamics Pub Date : 2025-08-29 DOI: 10.1007/s00162-025-00753-1

Reza T. Batley, Frank T. Smith

{"title":"Channel Flow with an Ice Constriction: Direct Simulation and Reduced-System Analysis","authors":"Reza T. Batley, Frank T. Smith","doi":"10.1007/s00162-025-00753-1","DOIUrl":"10.1007/s00162-025-00753-1","url":null,"abstract":"<div><p>The study here is of two-dimensional constricted channel flows and insight into their properties as the degree of constriction varies. This is potentially helpful for a range of applications as well as being of basic scientific interest. Two main computational approaches are taken, one via direct numerical simulation of the Navier-Stokes equations, and the other in the large Reynolds number limit where the boundary layer equations apply wall-to-wall. The focus is on understanding more of, and quantifying, the relatively unknown effects of wall icing in channel flow of water, as well as making quantitative comparisons between solutions from the two computational approaches and similar comparisons with recent work on the melting of wall-mounted ice. Flow separation, eddy lengths, pressure responses for sufficiently constricted internal vessels and upstream or downstream influence are examined. The retention of the ice when undercooling is present at the vessel wall is also studied. Severe blocking followed by eventual mild blocking or complete unblocking of the water flow is commonly found.</p></div>","PeriodicalId":795,"journal":{"name":"Theoretical and Computational Fluid Dynamics","volume":"39 5","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00162-025-00753-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144918364","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