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High-order thread-safe lattice Boltzmann model for high performance computing turbulent flow simulations Phys. fluids (IF 4.6) Pub Date : 2024-03-27 Andrea Montessori, Michele La Rocca, Giorgio Amati, Marco Lauricella, Adriano Tiribocchi, Sauro Succi
We present a highly optimized thread-safe lattice Boltzmann model in which the non-equilibrium part of the distribution function is locally reconstructed via recursivity of Hermite polynomials. Such a procedure allows the explicit incorporation of non-equilibrium moments of the distribution up to the order supported by the lattice. Thus, the proposed approach increases accuracy and stability at low
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Evaporation of bacteria-laden surrogate respiratory fluid droplets: On a hydrophilic substrate vs contact-free environment confers differential bacterial infectivity Phys. fluids (IF 4.6) Pub Date : 2024-03-27 Amey Nitin Agharkar, Dipasree Hajra, Durbar Roy, Vivek Jaiswal, Prasenjit Kabi, Dipshikha Chakravortty, Saptarshi Basu
The transmission of viruses/bacteria causes infection predominantly via aerosols. The transmission mechanism of respiratory diseases is complex, which includes direct or indirect contact, large droplet, and airborne routes apart from close contact transmission. With this premise, two modes of droplet evaporation are investigated to understand its significance in airborne disease transmission; a droplet
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Leakage vortices and energy characteristics of semi-open sewage pump with various blade tip alterations Phys. fluids (IF 4.6) Pub Date : 2024-03-27 Yang Yang, Hui Wang, Xionghuan Chen, Jiaxian Li, Weixuan Jiao, Leilei Ji, Zhaoming He, Weidong Shi, Ling Zhou
As one of the most commonly used fluid machineries, sewage pumps play a critical role in various sectors, including urban construction, industry, and environmental protection. Considering the clog-resistant performance, the impeller usually uses a semi-open structure, giving rise to a tip structure that introduces leakage flow. This exacerbates the instability of flow within the pump, thereby impacting
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Interdisciplinary approaches to modeling extraction efficiency and safety for clean energy under coupled multi-field effects Phys. fluids (IF 4.6) Pub Date : 2024-03-27 Dayu Ye, Guannan Liu, Feng Gao, Lei Wen, Zengqiang Wei, Danqi Li
Coal bed methane, a crucial clean energy source, has attracted extensive research attention. Characterized by intricate and rough fracture systems, coal seam is vital for gas migration, which will be influenced by the in situ stress, coal temperature, adsorption–desorption effect, solid deformation, and gas pressure. This paper introduces an innovative, interdisciplinary fractal model that addresses
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Planar wall plumes bounded by vertical and inclined surfaces Phys. fluids (IF 4.6) Pub Date : 2024-03-27 Santiago L. Zúñiga, S. Balachandar, Y. Yang, Y. Zhang, K. Smith, N. Loppi, M. I. Cantero, S. Kerkemeier
Planar wall plumes are gravity-driven flows where a fluid of lower (or higher) density than the ambient rises (or lowers) along a vertical or inclined wall. This study investigates planar wall plumes at five different wall slopes, ranging from a vertical wall (θ=90°) to a shallow inclination of θ=3°, using highly resolved direct numerical simulations. The three-dimensional turbulent structure of these
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Primary breakup model development for trajectory prediction of liquid jets in subsonic crossflow Phys. fluids (IF 4.6) Pub Date : 2024-03-27 Mingyun Xie, Wei Wang, Bin Yu, Miaosheng He, Shengqi Wu, Xiaobin Huang, Hong Liu
A comprehensive theoretical model for the primary breakup of liquid jets in subsonic crossflow was developed. The model theoretically analyzed the jet deformation process, mass stripping process, and the influence of several critical forces and consequently provided highly accurate predictions of the jet trajectory. Deformation of the liquid jet cross section was considered as a two-stage process based
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Spectral feature extraction of rocket exhaust plume using spectral proper orthogonal decomposition Phys. fluids (IF 4.6) Pub Date : 2024-03-27 Ao Sun, Qinglin Niu, Shikui Dong
The spectral characterization of flow-field parameters provides a new perspective for understanding the spatiotemporal evolution of unsteady supersonic exhaust plumes and for extracting typical structures. In this study, a large-eddy simulation is performed to calculate the three-dimensional unsteady supersonic plume flow field of rocket engines, and a spectral proper orthogonal decomposition (SPOD)
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New similarity laws reduced from local Mach factors in longitudinal–transverse force theory Phys. fluids (IF 4.6) Pub Date : 2024-03-27 Fanrong Xue, Ming Zhao, Shufan Zou, Jinyang Zhu, Wei Liu, Xiaogang Deng
The rapid advancement in aeronautics has led to the emergence of intricate dynamic processes and structures, such as vortices, shock waves, flow separation, and turbulence, resulting from the flow around airfoils. Acquiring a profound understanding of these local structures and unraveling the physical mechanisms underlying flow phenomena represents an essential and challenging issue in the field of
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Corrosion of welding reinforcement height under dynamic conditions Phys. fluids (IF 4.6) Pub Date : 2024-03-26 Xiaohui Dou, Hu Li, Wei Xiang, Xinwei Zhang, Zonghao He, Dalei Zhang, Bin Li, Yan Li
The presence of welding reinforcement height (WRH) within oil and gas pipelines can lead to micro-turbulence in localized areas during transportation, resulting in corrosion failure. This study employed a modular reconstruction method to simulate and reconstruct X80 steel welded joints, and investigated the erosion-corrosion behavior at the WRH using wire beam microelectrode, electrochemical impedance
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The complex unsteady flow exploration of a contra-rotating rotor under inlet distortion Phys. fluids (IF 4.6) Pub Date : 2024-03-26 K. Zhang, Y. Liu
This article explores the relationship between stall types and speed ratios in contra-rotating boost stages, discovering stationary circumferential stall cells and dual stall cell phenomena, and examines the relationship between stall characteristics and inlet distortions. These stall characteristics of counter-rotating boost stages are markedly different from the single stall patterns of traditional
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Turbulence generation in the transitional wake flow behind a sphere Phys. fluids (IF 4.6) Pub Date : 2024-03-26 Lin Niu, Hua-Shu Dou, Changquan Zhou, Wenqian Xu
Turbulence generation in the transitional flow in the wake behind a sphere is studied with numerical simulations. The filtered Navier–Stokes equation and the large eddy simulation method are employed as the governing equation and the numerical method, respectively. The ΩR̃ vortex identification method is used to trace the evolution of vortices in the wake flow. The energy gradient theory is used to
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Viscoplastic elliptical objects impacting a solid surface Phys. fluids (IF 4.6) Pub Date : 2024-03-26 Kindness Isukwem, Ramy Nemer, Elie Hachem, Anselmo Pereira
This theoretical and numerical study focuses on the physical mechanism driving the spreading of viscoplastic elliptical millimetric/centimetric objects after they impact a solid surface under no-slip conditions. The two-dimensional impacting objects are described as Bingham fluids. The two-dimensional numerical simulations are based on a variational multi-scale approach devoted to multiphase non-Newtonian
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Counter-current spontaneous imbibition dynamics: Combined effects of wettability, fracture flow, and pore structure Phys. fluids (IF 4.6) Pub Date : 2024-03-26 Yang Liu, Rongjiu Zhu, Ping Yu, Junhong Wang, Jun Zhao
Spontaneous imbibition plays a crucial role in various engineering and industrial applications, with its efficiency significantly influenced by a range of factors. To unravel the intricate mechanisms behind these factors, our study employs pore-scale numerical simulations. Utilizing a color gradient model within the framework of the lattice Boltzmann method, we delve into how pore structure, wettability
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Measurement of nonequilibrium vortex propagation dynamics in a nonlinear medium Phys. fluids (IF 4.6) Pub Date : 2024-03-26 Patrick C. Ford, Andrew A. Voitiv, Chuanzhou Zhu, Mark T. Lusk, Mark E. Siemens
We observe and measure the nonequilibrium dynamics of optical vortices as a function of propagation distance through a nonlinear medium. The precession of a tilted-core vortex is quantified as is vortex core sharpening, where the infinite width of a linear core subsequently shrinks and approaches the healing length of this nonlinear optical fluid. Experiments are performed with a variable-length nonlinear
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The importance of the inertial coupling in the two-fluid model of two-phase flow Phys. fluids (IF 4.6) Pub Date : 2024-03-26 Alejandro Clausse, Martín López-de-Bertodano
The new flux representation of the two-fluid model of two-phase flow, where the mixture is described in terms of the volumetric and drift fluxes, is currently the most consistent formulation to treat the inertial coupling between phases. In this representation, the dynamics of the relative motion between phases is revealed as a non-linear wave propagation equation. It is shown that the character and
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Hemodynamics in left coronary artery with ramus intermedius: A patient-specific computational study Phys. fluids (IF 4.6) Pub Date : 2024-03-26 Mudrika Singhal, Raghvendra Gupta, Bishwajeet Saikia, Amit Malviya, Amitav Sarma, Pranjal Phukan, Donboklang Lynser
Clinical studies based on coronary computed tomography angiography (CCTA) images suggest that the presence of ramus intermedius (RI) in the left coronary artery (LCA) may aggravate the atherosclerotic depositions in the furcation region. In this study, computational fluid dynamics simulations are performed in patient-specific coronary models consisting of bifurcating LCA and two models having trifurcating
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Wall effect on single bubble rising in a Hele–Shaw cell Phys. fluids (IF 4.6) Pub Date : 2024-03-26 Zhen Jian, Shiping Xiang, Ruixuan Li, Zhen Jiang, Lang Qin, Xurui Zhang
Single air bubble rising near vertical wall in a Hele–Shaw cell was investigated experimentally. Bubbles with a large range of size from 4.46 mm to 21.68 mm were generated. A vertical wall was introduced in the cell, and the initial distance between the wall and the bubble releasing position was varied systematically to study the wall effect on the rising dynamics. Rising trajectory, bubble morphology
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Integrability, breather, rogue wave, lump, lump-multi-stripe, and lump-multi-soliton solutions of a (3 + 1)-dimensional nonlinear evolution equation Phys. fluids (IF 4.6) Pub Date : 2024-03-26 Uttam Kumar Mandal, Amiya Das, Wen-Xiu Ma
In this article, we consider a new (3 + 1)-dimensional evolution equation, which can be used to interpret the propagation of nonlinear waves in the oceans and seas. We effectively investigate the integrable properties of the considered nonlinear evolution equation through several aspects. First of all, we present some elementary properties of multi-dimensional Bell polynomial theory and its relation
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Wave resonance mitigation using a rigid submerged breakwater in a varying-width channel Phys. fluids (IF 4.6) Pub Date : 2024-03-26 I. Magdalena, R. M. Valerio
This paper digs deeper into the phenomenon of wave oscillation that is caused by external forces, such as air pressure and seismic vibrations. This would eventually lead to potentially dire consequences, particularly in coastal areas. In order to solve this issue, this study focuses on adding a rigid breakwater at the bottom of the basin to minimize the aforementioned damages. We will be looking at
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Wetting boundary condition for three-dimensional curved geometries in lattice Boltzmann color-gradient model Phys. fluids (IF 4.6) Pub Date : 2024-03-26 Ningning Wang, Tie Kuang, Yong Liu, Zhilin Yin, Haihu Liu
A wetting boundary condition for handling contact line dynamics on three-dimensional curved geometries is developed in the lattice Boltzmann color-gradient framework. By combining the geometrical formation and the prediction-correction wetting scheme, the present wetting boundary condition is able to avoid the necessity to select an appropriate interface normal vector from its multiple solutions in
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Lattice Boltzmann simulations of quasi-steady film and axisymmetric nucleate boiling Phys. fluids (IF 4.6) Pub Date : 2024-03-26 Tahani Alsadik, Samuel W. J. Welch, Kannan N. Premnath
An axisymmetric multiple relaxation time lattice Boltzmann method utilizing the Shan-Chen pseudo-potential model is developed and combined with an axisymmetric finite difference approximation of the energy equation to form a hybrid method with a view toward studying axisymmetric nucleate boiling. The mechanism of phase change in the Shan–Chen model is investigated, and the model is validated by simulating
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Streaming potential of viscoelastic fluids with the pressure-dependent viscosity in nanochannel Phys. fluids (IF 4.6) Pub Date : 2024-03-26 Xingyu Chen, Zhiyong Xie, Yongjun Jian
The plane Poiseuille flow of viscoelastic fluids with pressure-dependent viscosity is analyzed through a narrow nanochannel, combining with the electrokinetic effect. When the fluid viscosity depends on pressure, the common assumption of unidirectional flow is unsuitable since the secondary flow may exist. In this case, we must solve the continuity equation and two-dimensional (2D) momentum equation
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Kriging-based multi-objective optimization on high-speed train aerodynamics using sequential infill criterion with gradient information Phys. fluids (IF 4.6) Pub Date : 2024-03-26 Zhiyuan Dai, Tian Li, Siniša Krajnović, Weihua Zhang
For models with large numerical simulation costs, such as high-speed trains, using as few samples as possible to construct a high-precision surrogate model during aerodynamic multi-objective optimization is critical to improving optimization efficiency. This study proposes a sequential infill criterion (SIC) appropriate for the Kriging surrogate model to address this issue. Three multi-objective functions
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Experimental study on vertical water entry of the projectile with canard-wing Phys. fluids (IF 4.6) Pub Date : 2024-03-26 Wenpeng Li, Cong Wang, Yingjie Wei, Shengsheng Xia, Yanyi Ding
Flow control techniques play an important role during water entry. In this paper, the idea of water entry of the projectile with single canard-wing is proposed and applied to the water entry problem. The cavity evolution and motion characteristics of projectile with canard-wing were investigated through experiments, and the cavity length, trajectory, and attitude changes of projectile with canard-wing
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Wall-modeled large eddy simulation in the immersed boundary-lattice Boltzmann method Phys. fluids (IF 4.6) Pub Date : 2024-03-25 Li Wang, Zhengliang Liu, Bruce Ruishu Jin, Qiuxiang Huang, John Young, Fang-Bao Tian
This work presents the wall-modeled large eddy simulation (WMLES) in the immersed boundary-lattice Boltzmann method (IB-LBM). Here, the wall model with both diffusive- and sharp-interface immersed boundary methods (IBMs) is incorporated into the IB-LBM to handle the turbulent boundary layer in high Reynolds number turbulent flows. To maintain the numerical stability, two collision models, i.e., mu
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Coupling numerical simulation of plasma arc channel evolution and particle dispersion process Phys. fluids (IF 4.6) Pub Date : 2024-03-25 Da Zhang, Tiejian Yuan, Yuanzheng Tang, Ruixin Ding, Lansen Bi, Song Shi, Yan He
Arc discharge plasma (ADP) technology can be applied to disperse easily aggregated materials, such as the carbon nanotubes and Fe3O4. To investigate the evolution of the plasma arc channel and particle dispersion effect during the ADP process, a coupled electrode–plasma channel–workpiece (Fe3O4 clusters) and particle dispersion heat transfer model was established. The simulation results exhibited that
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Dynamical wetting transition of a stretched liquid bridge Phys. fluids (IF 4.6) Pub Date : 2024-03-25 Zhenghao Shao, Peng Gao
The liquid bridge is an important model problem in printing processes. We report the experimental results of stretching a highly viscous liquid bridge between two parallel plates. Depending on the stretching speed, a thin liquid bridge exhibits two representative flow regimes. At low stretching speeds, the liquid bridge deforms in a quasi-static manner and no liquid films are observed. When the stretching
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A comprehensive review on the modeling of tropical cyclone boundary layer wind field Phys. fluids (IF 4.6) Pub Date : 2024-03-25 Yu Chang, Jiayao Wang, Sunwei Li, P. W. Chan
Tropical cyclone (TC) wind field models are becoming increasingly sophisticated and complex. This review systematically discusses a range of models capable of simulating TCs in terms of modifications or simplifications of the governing equation, the Navier–Stokes equations, as a starting point. The discussion focuses on linear models, which include slab models, height-resolving models, and numerical
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Experimental verification of rotating detonation engine with film cooling Phys. fluids (IF 4.6) Pub Date : 2024-03-25 Jingtian Yu, Songbai Yao, Jingzhe Li, Jianghong Li, Rujia Wang, Bin Wang, Wenwu Zhang
In this short letter, we report an experimental investigation on the integration of film cooling for thermal protection in a 72-mm cylindrical rotating detonation engine (RDE). The cooling scheme involves injection of cooling air through a series of cat-ear-shaped film cooling holes densely distributed along the outer wall of the cylindrical combustor. Our findings reveal the successful initiation
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A residual graph convolutional network for setting initial flow field in computational fluid dynamics simulations Phys. fluids (IF 4.6) Pub Date : 2024-03-25 Xiaoyuan Zhang, Guopeng Sun, Peng Zhang, Yueqing Wang, Jian Zhang, Liang Deng, Jie Lin, Jianqiang Chen
The computational cost of computational fluid dynamics (CFD) simulation is relatively high due to its computational complexity. To reduce the computing time required by CFD, researchers have proposed various methods, including efficient time advancement methods, correction methods for discrete control equations, multigrid methods, reasonable initial field setting methods, and parallel methods. Among
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Rheological behavior of high-pour-point oil: Insights into viscosity–temperature prediction and viscoelastic-yielding transition Phys. fluids (IF 4.6) Pub Date : 2024-03-25 Xuechen Tang, Yiqiang Li, Zhanqun Hu, Chuanmin Xiao, Zheyu Liu, Xiaolong Lv
The rheological characteristics of high-pour-point (high-PPT) oil are crucial for its economical and safe production and transportation. However, current research on the viscosity–temperature prediction and viscoelastic-yielding transition of high-PPT oil is insufficient. The Arrhenius formula faces challenges in accurately depicting the viscosity–temperature relationship, and there is a lack of a
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Impact dynamics of non-spherical droplets on a thin water film Phys. fluids (IF 4.6) Pub Date : 2024-03-25 Talha Khan, Zheyan Jin, Zhigang Yang
A droplet impinging on a liquid film finds numerous applications in diverse scientific fields. Although studies have primarily focused on spherical droplets, a droplet can present both spherical shape and non-spherical shape at the moment of impact. In the present study, the impact dynamics of a non-spherical droplet on a thin liquid film is investigated experimentally. The results show that, under
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Numerical investigation of flow past a cylinder using cumulant lattice Boltzmann method Phys. fluids (IF 4.6) Pub Date : 2024-03-25 Enbo Xing, Guangwei Liu, Qinghe Zhang, Jinfeng Zhang, Chaoqun Ji
This paper presents simulations of flow past a circular cylinder within the subcritical Reynolds number (Re) range from 3900 to 2 × 105, utilizing the parameterized cumulant lattice Boltzmann model. In this study, a three-dimensional characteristic boundary condition for incompressible flow has been integrated into the lattice Boltzmann method at the outflow boundary to minimize spurious reflection
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Detecting the large-scale wall-attached structural inclination angles by a machine learning perspective in turbulent boundary layer Phys. fluids (IF 4.6) Pub Date : 2024-03-22 Xuebo Li, Xin Hu, Lan Hu, Peng Li, Wanting Liu
With the recent advances in machine learning, strategies based on data can be used to augment wall modeling in the turbulent boundary layer. Combined with the attached eddy hypothesis, the present work applies extreme gradient boosting (XGBoost) to predict the large-scale wall-attached structures at a range of wall-normal locations based on a near-wall reference position (zR+≈4) spanning a Reynolds-number
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A numerical and experimental investigation into the mixing mechanism of hydrogen transverse jets into an air swirl flow Phys. fluids (IF 4.6) Pub Date : 2024-03-22 Tieyi Tan, Weijun Fan, Rongchun Zhang
As a clean fuel with the advantages of abundant reserves, high calorific value, renewability, and zero carbon emissions, hydrogen has broad application prospects in the fields of energy and power. Moreover, the mixing characteristics of hydrogen and air play a crucial role in determining combustion performance. A novel mixing method of hydrogen transverse jets into an air swirl flow was investigated
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Physics-informed neural networks for transonic flow around a cylinder with high Reynolds number Phys. fluids (IF 4.6) Pub Date : 2024-03-22 Xiang Ren, Peng Hu, Hua Su, Feizhou Zhang, Huahua Yu
The physics-informed neural network (PINN) method is extended to learn and predict compressible steady-state aerodynamic flows with a high Reynolds number. To better learn the thin boundary layer, the sampling distance function and hard boundary condition are explicitly introduced into the input and output layers of the deep neural network, respectively. A gradient weight factor is considered in the
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Investigating arc and molten metal transport phenomena in gas metal arc welding with Ar–CO2 gas mixtures using a numerical method Phys. fluids (IF 4.6) Pub Date : 2024-03-22 Xuefei Cui, Ji Chen, Maoai Chen, Chuansong Wu
This paper presents a numerical investigation of the transient transport phenomena of the arc and molten metal during gas metal arc welding (GMAW) using shielding gas mixtures ranging from 100% Ar + 0% CO2 to 80% Ar + 20% CO2. The thermophysical parameters of the Ar–CO2 mixtures, considering the presence of metal vapor, were calculated as a function for a temperature range of 1000–30 000 K. The influence
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Extraction of geometric features and analysis of flow mechanism of high loaded compressor airfoils at low Reynolds number Phys. fluids (IF 4.6) Pub Date : 2024-03-22 Ziyun Zhang, Yanhui Wu, Zhengtao Guo, Jiezhong Dong
When the aircraft cruising at high altitude, the aerodynamic performance of the compressor sharply decreases due to the enhanced boundary layer separation loss. Therefore, it is of great significance to design the high-performance airfoils suitable for low Reynolds numbers (Re) to improve the aerodynamic performance of compressor. In this paper, numerical simulations were carried out on a high-loaded
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A practical guide to mitigate edge fracture instability in sheared polymer melts Phys. fluids (IF 4.6) Pub Date : 2024-03-22 Benke Li, Christina Pyromali, Salvatore Costanzo, Antonios Mavromanolakis, Dimitris Vlassopoulos
The measurement of nonlinear shear response of viscoelastic materials is often hindered by edge fracture instabilities. The phenomenon was first addressed theoretically by Tanner and Keentok and ever since has attracted the interest of experimentalists and theorists alike. Despite progress, accounting for or mitigating edge fracture remains a challenge, in particular when dealing with strongly viscoelastic
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Modulated dust-ion-acoustic waves result from Earth's magnetosphere and lunar ionosphere interactions Phys. fluids (IF 4.6) Pub Date : 2024-03-22 R. E. Tolba, W. M. Moslem, R. Sabry
The Earth's magnetosphere's modulational amplitude dust-ion-acoustic waves are studied. When the moon passes through the Earth's magnetotail, its dust grains may interact, causing these waves. The theoretical plasma model for this study includes positive ionospheric ion fluids, isothermal electrons, and fluid-negative dust grains on the moon. A perturbation technique derived the nonlinear Schrödinger
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Effect of the heave plate's diameter on the transitional motions of a straked marine circular cylinder under different marine conditions Phys. fluids (IF 4.6) Pub Date : 2024-03-22 Mahdi Bandizadeh Sharif, Hassan Ghassemi, Guanghua He, Pengfei Liu
This numerical study investigated the influence of the heave plate's diameter on the amplitude of the transitional motions of a marine circular cylinder (MCC) with a low aspect ratio under the marine current and regular waves. Due to the experimental model of the straked MCC, different diameters of the circular heave plate were chosen to be installed at the keel of the 3-straked MCC. In this numerical
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Ensemble variational method with adaptive covariance inflation for learning neural network-based turbulence models Phys. fluids (IF 4.6) Pub Date : 2024-03-22 Qingyong Luo, Xin-Lei Zhang, Guowei He
This work introduces an ensemble variational method with adaptive covariance inflation for learning nonlinear eddy viscosity turbulence models where the Reynolds stress anisotropy is represented with tensor-basis neural networks. The ensemble-based method has emerged as an important alternative to data-driven turbulence modeling due to its merit of non-derivativeness. However, the training accuracy
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A circle-based interface reconstruction algorithm based on the coupled volume-of-fluid and level set method Phys. fluids (IF 4.6) Pub Date : 2024-03-22 Yujie Chen, Junhua Gong, Wei Lu, Bohong Wang, Dongliang Sun, Bo Yu, Wei Zhang, Wenquan Tao
The interface tends to behave as a circular shape under the effect of surface tension in the two-dimensional two-phase fluid flow. In this study, based on the coupled volume-of-fluid and level set (VOSET) method, an accurate circle-based interface reconstruction (CIR) algorithm for structured meshes is proposed, which features a straightforward implementation procedure. A portion of the standard circle
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Spontaneous motion of solid object on open channel Phys. fluids (IF 4.6) Pub Date : 2024-03-22 Dong Song, Xiang Wang, Changshen Xu, Yonghe Liu, Qiaogao Huang
Spontaneous motion of a solid object floating on an unsymmetrical geometric open channel is investigated. The open channel was created by selectively fabricating hydrophilic patterns on a superhydrophobic substrate, confining water within the hydrophilic region, thus forming a distinct open channel. As a rectangular foam block was placed on a triangular open channel, the variation of the spanwise width
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Deicing and status characteristics of dual-side pulsed surface dielectric barrier discharge Phys. fluids (IF 4.6) Pub Date : 2024-03-22 Bangfa Peng, Jie Li, Nan Jiang, Yan Jiang, Zhanqing Chen, Zhipeng Lei, Jiancheng Song
The deicing process and its status characteristics of dual-side pulsed surface dielectric barrier discharge (SDBD) are studied via electro-optical diagnostics, thermal properties, and numerical simulation. Experimental results show that the dual-side pulsed SDBD can remove the glaze ice compared to the traditional pulsed SDBD under the applied pulse voltage of 8 kV and a pulse frequency of 1 kHz. The
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Deformation and breakup of a ferrofluid droplet in shear flow under magnetic field Phys. fluids (IF 4.6) Pub Date : 2024-03-22 Yuto Kawabata, Shunichi Ishida, Yohsuke Imai
Effects of magnetic field applied perpendicular to a shear plane in shear flow on the deformation of a ferrofluid droplet are numerically investigated. The boundary integral method is employed to solve the two-phase Stokes flow under a uniform magnetic field. When the magnetic field is applied perpendicular to the shear plane, the deformation of the droplet in the shear plane decreases. The magnetic
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Numerical investigation on the effect of bionic fish swimming on the vortex-induced vibration of a tandemly arranged circular cylinder Phys. fluids (IF 4.6) Pub Date : 2024-03-22 Hongjun Zhu, Yingmei Li, Jiawen Zhong, Tongming Zhou
The effect of bionic fish swimming on the vortex-induced vibration (VIV) of a circular cylinder arranged in tandem at a low Reynolds number of 150 is numerically investigated in this work. The bionic fish placed upstream of the cylinder with gap ratios of 1, 3, and 5 and that located downstream of the cylinder with gap ratios of 3 and 5 are examined in the simulations that were carried out in the reduced
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Experimental study of the vortex-induced vibration of a circular cylinder considering coupling effect in along- and across-wind direction Phys. fluids (IF 4.6) Pub Date : 2024-03-21 Qingshan Yang, Chao Li, Kunpeng Guo, Wenshan Shan, Shuai Huang
Tower-like structures with circular section are prone to unexpected across-wind vortex-induced vibration (VIV), and the along-wind response is usually neglected due to its amplitude being much smaller than that of VIV. Recent research pertaining to tall buildings has revealed, nevertheless, that the structural responses in the along-wind and across-wind directions are coupled in a way that results
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Combustion of a nanoparticles-laden chemical in a vented cavity Phys. fluids (IF 4.6) Pub Date : 2024-03-21 Nepal Chandra Roy
Mixed convective characteristics of the combustion of a nanoparticles-laden fuel (n-butanol nanofluid) in a vented cavity are investigated. The nanofluid and the oxidizer enter the cavity through the inlets on the left and right vertical walls, respectively. However, the resulting product produced from the oxidation process of the fuel exits the cavity through the outlet at the bottom wall. Heat generated
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How do various forces affect pressure waves in bubbly flows? Phys. fluids (IF 4.6) Pub Date : 2024-03-21 Shuya Arai, Tetsuya Kanagawa
This study investigated the weakly nonlinear propagation of pressure waves in compressible, flowing water with spherical microbubbles, considering various forces. Previous theoretical studies on nonlinear pressure waves in bubbly flows did not consider the forces acting on the bubbles, although the validity of ignoring these forces has not been demonstrated. We focused on every possible force such
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Aerodynamic center of a wing at low Reynolds number Phys. fluids (IF 4.6) Pub Date : 2024-03-21 Arnesh Maji, Jawahar Sivabharathy Samuthira Pandi, Sanjay Mittal
The location of the aerodynamic center, with respect to the center of gravity, determines the longitudinal static stability of an aerial vehicle. While most studies in the past focused on high Reynolds number (Re) flows, we consider flows at low Re (100≤Re≤6000) past an end-to-end wing and a finite wing of various semi-aspect ratio (0.25≤sAR≤5). It is shown that two-dimensional computations, even for
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Influence of swirl intensity on combustion dynamics and emissions in an ammonia-enriched methane/air combustor Phys. fluids (IF 4.6) Pub Date : 2024-03-21 Chunyu Liu, Haojie Yang, Can Ruan, Liang Yu, Xingcai Lu
Ammonia (NH3) has been widely considered as a promising carbon-free energy and hydrogen carrier for various applications. The large-scale direct utilization of NH3 as fuel in gas turbine engines is currently attracting significant interest, with strong focuses on improving the efficiency and stability of the system and reducing the emissions of pollutants. The present study experimentally examined
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Data-driven modal decomposition of R134a refrigerant cavitating flow in Venturi tube Phys. fluids (IF 4.6) Pub Date : 2024-03-21 Beile Zhang, Ze Zhang, Xufeng Fang, Rong Xue, Shuangtao Chen, Yu Hou
This study utilized high-speed camera and large eddy simulation methods to explore the cavitating flow mechanisms and turbulence structures of R134a refrigerant inside a Venturi tube under varying cavitation numbers (CNs). Data-driven modal analysis approaches, proper orthogonal decomposition (POD) and dynamic mode decomposition (DMD), were introduced to identify and extract the energy hierarchy and
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An investigation of the effect of stratification stability and saltation sand flux on the anisotropy of atmospheric surface layer wall turbulence Phys. fluids (IF 4.6) Pub Date : 2024-03-21 Ao Mei, Yulin Zhu, Shanlin Zhou, Yongan Liao, Chentao Huang, Mingyang Li, Tingting Leng
In the atmospheric surface layer (ASL), the anisotropic characteristics of turbulence become more complex due to the strong influence of heat flux and particle motion. In this paper, the effects of stratification stability and total saltation sand flux on turbulent anisotropy of ASL wall turbulence are systematically analyzed by using high-frequency 3D velocity, temperature, and saltation sand flux
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Heating from above in non-scattering suspension: Phototactic bioconvection under collimated irradiation Phys. fluids (IF 4.6) Pub Date : 2024-03-21 Sandeep Kumar, Shaowei Wang
Examining phototactic bioconvection in non-scattering suspensions with upper heating and collimated irradiation, this study delves into the intricate dynamics influenced by light and microorganisms. The study focuses on the linear stability of the basic state, examining neutral curves. The numerical analysis involves solving a system of equations using the MATLAB bvp4c solver. The investigation considers
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A sectional method to estimate the transmission coefficients of a new type pile-supported permeable breakwater Phys. fluids (IF 4.6) Pub Date : 2024-03-21 Xinying Pan, Dan Wu, Bingchen Liang, Guoxiang Wu
This article investigates the transmission coefficient of a novel pile-supported permeable breakwater featuring inclined porous plates under regular waves. To analyze the transmission coefficient, we propose a sectional method that involves multiplying the transmission coefficients of three distinct sections: the upper retaining wall and porous plates, the horizontal platform, and the piles. The calculation
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A numerical study of natural convection through a vertical heated channel with a confined circular cylinder Phys. fluids (IF 4.6) Pub Date : 2024-03-21 Quang Duy Nguyen, Siyu Ji, Chengwang Lei
This study examines thermal flow structures and heat transfer through a vertical heated channel with an adiabatic circular cylinder symmetrically positioned between lateral walls. A two-dimensional numerical simulation is conducted covering a range of parameters including Rayleigh numbers Ra = 8.9 × 106–8.9 × 108, cylinder positions relative to the channel height h = 0–0.50, and blockage ratios (the
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Probabilistic learning approach for the liquid holdup analysis of high-viscosity intermittent flows Phys. fluids (IF 4.6) Pub Date : 2024-03-21 J. E. V. Guzmán, J. A. González-Treviño, L. Torres, F. Aragón-Rivera, J. Hernández-García, A. Palacio-Pérez, J. Klapp
A Gaussian mixture model (GMM) was implemented to investigate the relationship between the liquid holdup (in various parts of the flow) and the pressure for different experimental realizations of high-viscosity gas–liquid flows. We considered a Newtonian fluid with a constant viscosity of 6 Pa s (600 cP) under a laboratory-controlled temperature. Because the pressure and the holdup do not exhibit a
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Investigation of cavitation shedding mechanisms including reentrant jet and shock wave by Eulerian–Lagrangian multiscale simulation Phys. fluids (IF 4.6) Pub Date : 2024-03-21 Linmin Li, Xiang Cheng, Zuchao Zhu, Xun Sun, Xinglin Zhang
Sheet-to-cloud cavitation in a Venturi pipe is investigated experimentally and numerically in this work. The multiscale vapor structures are simulated by Eulerian–Lagrangian multiscale modeling. The volume of fluid method with adaptive mesh refinement is employed to capture the macroscale cavity features, utilizing the large eddy simulation approach. The results of mesh sensitivity study demonstrate
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Linear and nonlinear stability analyses of micropolar fluid flow in horizontal porous layers Phys. fluids (IF 4.6) Pub Date : 2024-03-21 Pankaj Barman, Srinivasacharya D.
The linear and nonlinear stability analyses of micropolar fluid flow in a horizontal porous layer heated from below in the presence of throughflow is numerically investigated. The Brinkman model is considered to govern the micropolar fluid flow within the porous region. The main purpose of the present study is to investigate the behavior of the subcritical region for micropolar fluid parameters in