Article
Engineering, Marine
Duo Yu, Yu Zhao, Mei Li, Haitian Liu, Suoxian Yang, Liang Wang
Summary: Propeller wake fields in an open-water configuration were compared between two loading circumstances using large-eddy simulation. The results indicate that the present simulations describe the inertial frequency range well for both high and low-loading conditions. Under high-loading conditions, interlaced spirals and secondary vortices amplify the effects of mutual inductance, ultimately triggering the breakdown of the propeller wake systems. In contrast, under light-loading conditions, the wake vortex system exhibits strong coherence and has a relatively simple topology.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Mechanics
Fangjuan Guo, Gefei Wu, Xiaoqing Du, Matthew S. Mason
Summary: This study investigated the flow field evolution and aerodynamic characteristics of a square cylinder during flow acceleration using large-eddy simulations. The results revealed three distinct temporal flow phases, including a phase without vortex shedding, a phase with periodic shedding and enhanced lift force oscillations, and a phase with stable shedding. The study also provided detailed insights into the transient lift and drag coefficients, wind pressure distributions, and spatial evolution of three-dimensional flow structures and pressure distributions.
Article
Engineering, Electrical & Electronic
Monkami Masale, Moletlanyi Tshipa
Summary: The scattering rates of electrons interacting with longitudinal optical phonon modes in a hollow cylinder are calculated based on the inner radius and axial magnetic field. The study focuses on the interaction of electron-phonon interactions and the energy transitions in electron subbands in different conditions.
OPTICAL AND QUANTUM ELECTRONICS
(2021)
Article
Mechanics
Xiang-Fei Zhang, Juan-Cheng Yang, Ming-Jiu Ni, Nian-Mei Zhang, Xin-Gang Yu
Summary: This study aims to understand the magnetohydrodynamic (MHD) flow around two identical tandem circular cylinders confined in a duct under an external axial magnetic field. The effects of magnetic field, inlet velocity of conducting fluid, and the gap ratio on the flow regimes, vortex shedding frequency, pressure coefficients, drag coefficients, and pressure drop are investigated. Four flow modes are observed, and the flow field presents the vortex shedding (VS) flow model for L/d > 5. The magnetic field and inlet velocity of the metal fluid have linear effects on the pressure drop delta P between the inlet and outlet.
Article
Engineering, Electrical & Electronic
Fengwen Zhao, Xiangyang Zhou, Weiyong Zhou, Xu Zhang, Kai Wang, Weiqian Wang
Summary: The study presents a novel method for designing highly uniform axial coils inside a closed magnetically shielded cylinder, using image method, target-field method, backpropagation neural network model and particle swarm optimization algorithm. The method successfully reduces magnetic field deviation and demonstrates practical significance for establishing magnetoencephalography and magnetocardiography measurement systems.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2022)
Article
Mechanics
Jiang-Hua Li, Bo-Fu Wang, Xiang Qiu, Jian-Zhao Wu, Quan Zhou, Shi-Xiao Fu, Yu-Lu Liu
Summary: This study numerically investigates the flow past a cylinder near a plane wall for small gap ratios, exploring the dynamics of cylinder-wake/boundary-layer interaction. The results show that the shedding of vortices and the generation of hairpin vortices play crucial roles in turbulent kinetic energy production. Furthermore, the redistribution of turbulent kinetic energy due to the generation of hairpin vortices can impact the growth rate of secondary disturbances and promote wall boundary layer transition.
Article
Engineering, Marine
Yanxu Bao, Yongshui Lin, Wei Chen, Chang-Kyu Rheem, Xiaobin Li
Summary: The flow-induced vibrations of a rotating cylinder with two degrees of freedom were investigated through numerical simulations. The study found that the vortex structure and trajectory of the cylinder vary with the rotation rate and reduced velocity. The wake transition from one pattern to another is accompanied by jumps in hydrodynamics and amplitudes.
Article
Chemistry, Physical
Md Rifat Hassan, Jie Zhang, Cheng Wang
Summary: This article presents a methodical analysis on the dynamic interaction behavior between a pair of uneven sized ferrofluid droplets freely falling under gravity and uniform magnetic fields. The results indicate that the separation distance and shape of the droplets are influenced by different magnetic field directions and surface tensions.
COLLOID AND INTERFACE SCIENCE COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Senlin Rao, Hanmeng Xiong, Qi Lei, Dongfu Xie, Junling Ding, Yufeng Luo, Xiao-hui Chen, Fayun Zhang
Summary: The effects of axial magnetic field on different directional solidification processes were studied through numerical simulation and experimentation. The study focused on the shape of the melt-crystal interface, melt flow morphology, thermal stress, and Fe impurity concentration in the crystal. Simulation results showed that the axial magnetic field led to a slight convex m-c interface shape, better flow pattern, lower thermal stress, and lower Fe impurity concentration throughout the process. Experimental results confirmed the simulation findings and demonstrated the benefits of using the axial magnetic field in achieving a slight convex m-c interface shape and lower Fe impurity concentration in the middle area of the ingot, leading to higher minority carrier lifetime.
Article
Engineering, Marine
Shun Xu, Tiegang Zhuang, Weiwen Zhao, Decheng Wan
Summary: This study conducts a numerical investigation on the aerodynamics and wakes of a semi-submersible floating offshore wind turbine (FOWT) under atmospheric boundary layer (ABL) inflow. The results indicate that the power variation of FOWT is mainly influenced by atmospheric turbulence rather than platform motions. The platform motions slightly enhance the out-of-plane shear force and bending moment of FOWT. Moreover, the entrance of ambient atmospheric flow into wind turbine wakes causes significant deflection of the wakes. The wake center of FOWT is located far from the hub height level due to the pitch motion of the platform, which is a potential benefit for downstream wind turbines.
Article
Mechanics
A. Posa, R. Broglia, E. Balaras
Summary: The flow around the rotor of an axial turbine operating in the wake of an upstream one is studied using large-eddy simulation. The results show that the tip vortices shed by the downstream rotor are strongly influenced by the disturbance produced by the wake of the upstream rotor. The development of the downstream rotor wake is faster and very similar across different distances from the upstream rotor.
Article
Engineering, Chemical
Dev S. Hathi, Pratik M. Panchal, Atul Sharma, Rochish Thaokar, Absar M. Lakdawala
Summary: The size and frequency of droplets in electrohydrodynamic jet printing can be manipulated by changing the electric field strength and flow rate. Numerical simulations show that there is a transition from dripping to micro-dripping and micro-jetting with increasing electric Bond number. The stability of the micro-dripping mode is determined by the balance of electrical and viscous shear stresses.
JOURNAL OF AEROSOL SCIENCE
(2023)
Article
Engineering, Marine
Xiaogang Yang, Zhitao Yan, Hengren Fu, Lingzhi Wang, Eric Savory
Summary: This paper aims to develop a nonlinear mathematical model for the unsteady wake galloping forces (UWGF) acting on a circular cylinder in the wake of a fixed identical circular cylinder. Numerical simulations are conducted to obtain the synchronous unsteady aerodynamic lift forces and displacements of wake galloping at different Reynolds numbers. The proposed UWGF model, which combines the self-excited force and the vortex-induced force based on the spectra of the aerodynamic lift forces, is verified by experimental results and can calculate wake galloping responses better than the quasi-steady theory.
Article
Thermodynamics
Nadeem Abbas, Wasfi Shatanawi, Taqi A. M. Shatnawi
Summary: In this analysis, the fluid flow of induced magnetic hydrodynamic on a stretchable cylinder is studied, considering viscosity dissipation and temperature-dependent properties. The governing equations are obtained using boundary layer approximation and dimensionless by suitable transformation. The influence of governing physical parameters is presented through graphs and tables. The velocity function curves show an increase with the decay-resistant parameter, as well as the magnetic field parameter. The relationship between the sponginess parameter and velocity is inverse. Temperature increases with the thermal conductivity.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Mechanics
Jianhan Liu, Wenyong Ma, Longqian Jin, Xinyue Liu, Tianxu Li
Summary: The study focused on investigating the wake flow and surface pressure characteristics of a rotating cylinder at different rotational speeds. Results showed that the dimensionless rotational speed affects vortex shedding intensity and pattern, as well as wind pressure distribution. Changes in the rotational speed also influence the characteristics of the wake flow's vortex shedding pattern and direction.
Article
Computer Science, Interdisciplinary Applications
Kacper Kornet, Alban Potherat
JOURNAL OF COMPUTATIONAL PHYSICS
(2015)
Article
Mechanics
Alban Potherat, Kacper Kornet
JOURNAL OF FLUID MECHANICS
(2015)
Article
Mechanics
Nathaniel T. Baker, Alban Potherat, Laurent Davoust
JOURNAL OF FLUID MECHANICS
(2015)
Article
Physics, Fluids & Plasmas
R. Low, A. Potherat
Article
Mechanics
Ahmad H. A. Hamid, Wisam K. Hussam, Alban Potherat, Gregory J. Sheard
Article
Mechanics
Kelig Aujogue, Alban Potherat, Binod Sreenivasan
Article
Instruments & Instrumentation
Kelig Aujogue, Alban Potherat, Ian Bates, Francois Debray, Binod Sreenivasan
REVIEW OF SCIENTIFIC INSTRUMENTS
(2016)
Article
Physics, Multidisciplinary
A. Potherat
Article
Chemistry, Physical
A. Potherat, F. Rubiconi, Y. Charles, V. Dousset
EUROPEAN PHYSICAL JOURNAL E
(2013)
Article
Mechanics
Vincent Dousset, Alban Potherat
JOURNAL OF FLUID MECHANICS
(2012)
Article
Mechanics
Alban Potherat, Rico Klein
JOURNAL OF FLUID MECHANICS
(2014)
Article
Engineering, Multidisciplinary
A. Alferenok, A. Potherat, U. Luedtke
MEASUREMENT SCIENCE AND TECHNOLOGY
(2013)
Article
Mechanics
Alban Potherat, Jean-Philippe Schweitzer
Article
Mechanics
Lintao Zhang, Alban Potherat
Article
Mechanics
A. Potherat
MAGNETOHYDRODYNAMICS
(2012)