Fluid Dynamics最新文献_第8页

Effect of Acoustic Excitation on Colliding Laminar Microjets

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2025-01-10 DOI: 10.1134/S0015462824603188

Yu. A. Litvinenko, A. A. Smyatskikh, M. V. Litvinenko

引用次数: 0

Electrodynamic Mechanism of Expansion of Two-Component Plasma in a Spherically Symmetric Vacuum Gap

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2025-01-10 DOI: 10.1134/S0015462824604601

A. O. Kokovin, V. Yu. Kozhevnikov, A. V. Kozyrev, N. S. Semenyuk

引用次数: 0

Axisymmetric Poiseuille Flow with Temperature-Dependent Viscosity under Pressure and Temperature Gradients

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2025-01-10 DOI: 10.1134/S001546282460367X

D. V. Knyazev

{"title":"Axisymmetric Poiseuille Flow with Temperature-Dependent Viscosity under Pressure and Temperature Gradients","authors":"D. V. Knyazev","doi":"10.1134/S001546282460367X","DOIUrl":"10.1134/S001546282460367X","url":null,"abstract":"The study of steady-state axisymmetric Poiseuille flow of a Newtonian fluid induced by streamwise pressure and temperature gradients in the case of the dynamic viscosity coefficient dependent on the temperature is reduced to finding solutions to a three-parameter boundary-value problem for a third-order ordinary differential equation. In the domain of the parameter space corresponding to negative axial temperature gradients, there exist two branches of solutions describing flows accompanied by heat removal from the fluid. When the branches meet, they form a boundary in the phase space beyond which no solutions to the Poiseuille-type problem exist. One of the branches can be continued into the domain of non-negative values of the streamwise temperature gradient and contains an isothermal Poiseuille solution. Along this branch, curve of the flow rate as a function of the dimensionless axial temperature gradient has a minimum in the domain of positive values of the latter. In this part of the parameter space, the heat exchange regime with the external medium depends on the relation between all three dimensionless numbers of the problem. The heat exchange regime affects the nature of flow, slowing down the flow near the rigid wall during heat transfer, and forming a more filled velocity profile when heat is absorbed by fluid.","PeriodicalId":560,"journal":{"name":"Fluid Dynamics","volume":"59 6","pages":"1741 - 1750"},"PeriodicalIF":1.0,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1134/S001546282460367X.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143423204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Reaction of Methane Replacement with Carbon Dioxide in Hydrate during Injection of Liquid Carbon Dioxide into Formation

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2025-01-10 DOI: 10.1134/S0015462824604674

G. G. Tsypkin

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Effect of Microstructure Surfaces on the Wetting State and Impact Spreading Behavior of Molten Aluminum Droplets

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-11-22 DOI: 10.1134/S0015462824603127

X. Lyu, Z. Y. Rui, H. M. Sun, H. B. Sun, D. Y. He, J. T. Zhuo, Y. Dong

引用次数: 0

Separation Lines for Laminar Separation Bubble and Propagation of Stall over Finite Wing at Transition Regime Reynolds Number

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-11-22 DOI: 10.1134/S0015462824602043

G. V. Kumar G, R. Mukherjee

{"title":"Separation Lines for Laminar Separation Bubble and Propagation of Stall over Finite Wing at Transition Regime Reynolds Number","authors":"G. V. Kumar G, R. Mukherjee","doi":"10.1134/S0015462824602043","DOIUrl":"10.1134/S0015462824602043","url":null,"abstract":"Flow separation over a 3D wing, both local at low angles of attack and that which begins at a section and then engulfs the entire wing at the higher angles of attack is studied using experiments and CFD. The pressure measured from pressure ports located on the root section of the 3D wing is used to calculate the pressure coefficient and oil flow visualization conducted to study separation lines. The location and length of the separated zone along wing-span is calculated. Statistical analysis of the data extracted from the oil flow visualization is used to generate curve-fit separation and reattachment lines. The data shows lines to be third-order polynomial. Study indicates that the location of laminar separation bubbles is more sensitive to the angle of attack as compared to the Reynolds number. At the higher angles of attack, the effect of the Reynolds number and the angle of attack on stall progression is studied. The velocity profile in the boundary layer at five different locations along wing-span is calculated at the angles of attack near complete wing stall. Sections near wing-root and the wing tips are studied in detail and inferences drawn on stall progression in cambered wing. A comprehensive study of flow separation and laminar separation bubble on a 3D wing can be used as basis of design for active flow control.","PeriodicalId":560,"journal":{"name":"Fluid Dynamics","volume":"59 5","pages":"1303 - 1327"},"PeriodicalIF":1.0,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

A Finite Volume Method-Discrete Element Method Solver for Simulating the Interaction between Water Waves and a Partially Consolidated Mud Bed

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-11-22 DOI: 10.1134/S0015462824602572

K. Hejazi, M. Soltanpour, M. H. Jabbari

{"title":"A Finite Volume Method-Discrete Element Method Solver for Simulating the Interaction between Water Waves and a Partially Consolidated Mud Bed","authors":"K. Hejazi, M. Soltanpour, M. H. Jabbari","doi":"10.1134/S0015462824602572","DOIUrl":"10.1134/S0015462824602572","url":null,"abstract":"A novel solver that combines the finite volume method and the discrete element method to investigate the interaction between progressive waves and a seabed composed of partially consolidated mud is proposed. The finite volume method is employed to solve the 2D Reynolds-averaged Navier–Stokes equations, employing an arbitrary Lagrangian Eulerian description to simulate the propagation of regular waves. The solver incorporates the kinematic boundary conditions at the free surfaces. Through a series of preliminary test cases, both the finite volume method and the discrete element method demonstrate satisfactory performance and are validated using available experimental data. Then, the presented finite volume method–discrete element method solvers are applied to analyze the interaction between water waves and the seabed, considering incompressible pores. The model is extended to simulate the dynamic interaction between waves and mud by incorporating particle–particle interaction. The partially consolidated mud beds are represented as assemblies of spherical particles. The numerical results are compared with experimental data, specifically focusing on the free surface time series, the hydrodynamic pressure, and the particle velocity components measured by wave gauges, pore pressure transducers, and electromagnetic current measurements, respectively. The results demonstrate a good agreement between the numerical and experimental findings. Notably, the estimation of cell porosity is identified as a crucial factor in achieving the accurate results when comparing the numerical and experimental data.","PeriodicalId":560,"journal":{"name":"Fluid Dynamics","volume":"59 5","pages":"1253 - 1276"},"PeriodicalIF":1.0,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Dynamic Modeling of Vertical Collision of Hollow and Dense Droplets on the Semicircular Surface in Spray Coating

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-11-22 DOI: 10.1134/S0015462822600742

H. Sayyari, M. M. Peiravi, J. Alinejad

引用次数: 0

Flow over a Rectangular Cylinder in Proximity to the Plane Wall: Effect of Cylinder Aspect Ratios and Power-Law Index

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-11-22 DOI: 10.1134/S0015462824603425

A. M. Tripathi, S. Sarkar, S. K. Ghosh

{"title":"Flow over a Rectangular Cylinder in Proximity to the Plane Wall: Effect of Cylinder Aspect Ratios and Power-Law Index","authors":"A. M. Tripathi, S. Sarkar, S. K. Ghosh","doi":"10.1134/S0015462824603425","DOIUrl":"10.1134/S0015462824603425","url":null,"abstract":"Newtonian (power-law index n = 1) and pseudoplastic (n = 0.8 and 0.5) fluid flow past a rectangular cylinder placed close to the plane wall (the gap ratio G/a varying from 0.25 to 1) is studied numerically using Ansys Fluent when the body shape of the cylinder changes from a bluff body (the aspect ratio AR = 0.5, 1, and 2) to an elongated body (AR = 3 and 4). The 2-D unsteady, incompressible Navier–Stokes equations with varying viscosity are solved at a constant Reynolds number, namely, Re = 100, using a second-order upwind momentum and least square cell-based pressure solver. The instantaneous and time-averaged flow fields are analyzed and compared in 45 cases concerning AR, n and G/a. It has been observed that the body shape of the cylinder and pseudoplasticity play pivotal roles in changing the flow field variables along with aerodynamic forces for a relatively intermediate and high gap ratio (G/a = 0.5 and 1, respectively). The quantity ({{bar {C}}_{L}}) increases and ({{bar {C}}_{D}}) reduces with increase in the AR value of the cylinder. In the presence of high pseudoplasticity in fluid flow (n = 0.5), this trend becomes more prominent. Also for n = 0.5, multiple values of Strouhal number (St) are obtained for a cylinder with low AR (AR = 0.5 and 1) at a large gap ratio (G/a = 1) owing to differences in the celerity of the vortices produced from outer and inner shear layers of the cylinder after the interactions. When the rectangular cylinder is kept very close to the plane wall (G/a = 0.25), vortex suppression occurs irrespective of the cylinder size or flow nature which negates the changes in the flow field and the aerodynamic forces.","PeriodicalId":560,"journal":{"name":"Fluid Dynamics","volume":"59 5","pages":"1371 - 1403"},"PeriodicalIF":1.0,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Aero-Optical Effect Similarity Law in Subsonic Flow over a Hemisphere-on-Cylinder Turret

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-11-22 DOI: 10.1134/S0015462824603541

Z. Pei, H. Y. Xu, X. T. Tan, K. Yin

{"title":"Aero-Optical Effect Similarity Law in Subsonic Flow over a Hemisphere-on-Cylinder Turret","authors":"Z. Pei, H. Y. Xu, X. T. Tan, K. Yin","doi":"10.1134/S0015462824603541","DOIUrl":"10.1134/S0015462824603541","url":null,"abstract":"All physics issues are expected to be solved with a concise expression, and the field of aero-optical effect is no exception. Due to the excessive influencing factors and coefficients that are difficult to determine, there are only a few available conclusions at present. Moreover, the validation of these conclusions is often inadequate due to their limited scope of applications. In this paper, the Reynolds averaged Navier–Stokes equations are used to simulate the flow field of a hemisphere-on-cylinder turret with various Mach numbers equal to 0.3, 0.4, and 0.5. The wavefront distortion of the beam is calculated using the ray-tracing method and Zernike fitting. The similarity law proposed by the predecessors is verified, and the variation trend of OPDsteady/[(ρ∞/ρSL)M2D] with window angle is studied for the first time. It is found that the functional relation between OPDsteady/[(ρ∞/ρSL)M2D] and the window angle is approximately quadratic. Based on the Prandtl–Glauert compressibility correction principle, the similarity law proposed by predecessors is improved.","PeriodicalId":560,"journal":{"name":"Fluid Dynamics","volume":"59 5","pages":"1341 - 1354"},"PeriodicalIF":1.0,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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