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Numerical simulation of the effect of upstream swirling flow on swirl meter performance

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Journal of Thermal Science 2018年第2期27卷 117-124页

作者： CHEN Desheng CUI Baoling ZHU Zuchao Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech University

flow measurement is important in the fluid process and transmission system. For the need of accuracy measure- ment of fluid, stable flow is acquired. However, the elbows and devices as valves and rotary machines may pro- duce swirling flow in the natural gas pipeline networks system and many other industry fields. In order to reveal the influence of upstream swirling flow on internal flow fields and the metrological characteristics, numerical si- mulations are carried out on the swirl meter. Using RNG k-e turbulent model and SIMPLE algorithm, the flow field is numerically simulated under swirling flows generated from co-swirl and counter-swirl flow. Simulation results show fluctuation is enhanced or weakened depending on the rotating direction of swirling flow. A coun- ter-swift flow increases the entropy production rate at the inlet and outlet of the swirler, the junction region between throat and divergent section, and then the pressure loss is increased. The vortex precession dominates the static pressure distributions on the solid walls and in the channel, especially at the end region of the throat.

关键词： Swirl meter Numerical simulation swirling flow vortex precession

Experimental and numerical study of the adsorption performance of a vortex suction device using water-swirling flow

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Science China(Technological Sciences) 2020年第6期63卷 931-942页

作者： ZHU YaWei ZHOU RenGuan YANG Gang ZHU YanQing HU DeAn State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China College of Electrical and Information Engineering Hunan UniversityChangsha 410082China

An electrically activated underwater suction device is designed to form an amazing amount of negative pressure by generating water swirling flow,which can make underwater wall-climbing robot stick to the wall surface allowing a ground *** the purpose of a full understanding of the mechanism of the suction device,a series of experimental tests are carried out and a computational fluid dynamics(CFD)model is *** results show that the suction force F is consistent between experimental tests and *** insight into the flow phenomena of vortex suction device,including spatial velocity and pressure distribution,is given through numerical simulation ***,the crucial parameters,i.e.,the rotation speedωand gap clearance h,are *** the relationships of F-ωand F-h are *** reveals that with the increasing of rotation speed,the suction force increases *** with the increasing of gap clearance,the suction force increases firstly and then decreases,so that a reasonable design interval of gap clearance can be got to obtain the required suction force for the engineering applications.

关键词： vortex suction device hydrodynamic analysis swirling flow underwater wall-climbing robot CFD

Tomographic particle image velocimetry measurement on three-dimensional swirling flow in dual-stage counter-rotating swirler

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Chinese Journal of Aeronautics 2024年第3期37卷 7-20页

作者： Yuyang ZHOU Ling DONG Mingtao SHANG Jibao LI Akira RINOSHIKA Key Laboratory of Fluid Mechanics of Ministry of Education Beihang UniversityBeijing 100191China School of Mechanical and Automotive Engineering Shanghai University of Engineering ScienceShanghai 201620China AECC Commercial Aircraft Engine Co. Ltd.Shanghai 200241China Department of Mechanical Systems Engineering Yamagata UniversityYamagata 992-8510Japan

Three-Dimensional(3D)swirling flow structures,generated by a counter-rotating dualstage swirler in a confined chamber with a confinement ratio of 1.53,were experimentally investigated at Re=2.3×10^(5)using Tomographic Particle Image Velocimetry(Tomo-PIV)and planar Particle Image Velocimetry(PIV).Based on the analysis of the 3D time-averaged swirling flow structures and 3D Proper Orthogonal Decomposition(POD)of the Tomo-PIV data,typical coherent flow structures,including the Corner Recirculation Zone(CRZ),Central Recirculation Zone(CTRZ),and Lip Recirculation Zone(LRZ),were *** counter-rotating dual-stage swirler with a Venturi flare generates the independence process of vortex breakdown from the main stage and pilot stage,leading to the formation of an LRZ and a smaller CTRZ near the nozzle *** confinement squeezes the CRZ to the corner and causes a reverse rotation flow to limit the shape of the CTRZ.A large-scale flow structure caused by the main stage features an explosive breakup,flapping,and Precessing Vortex Core(PVC).The explosive breakup mode dominates the swirling flow structures owing to the expansion and construction of the main jet,whereas the flapping mode is related to the wake *** limits the expansion of PVC and causes it to contract after the impacting area.

关键词： Coherent structures Dual-stage counter-rotating swirler cup Precessing vortex core Proper orthogonal decomposition swirling flow Tomographic particle image velocimetry

Numerical simulation on gas–liquid multiphase flow behavior under coupling effects of annular gas curtain and swirling flow at tundish upper nozzle

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Journal of Iron and Steel Research International 2024年第11期31卷 2693-2709页

作者： Xu-feng Qin Chang-gui Cheng Yang Li Wei-li Wu Hao Chen Chao-fa Zhao Yan Jin The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan430081HubeiChina

A three-dimensional mathematical model has been established for a novel metallurgy process coupling an annular gas curtain with swirling flow at tundish upper nozzle. The discrete phase model and volume of fluid model were applied to simulate the gas–liquid multiphase flow behavior in tundish and nozzle. The effect of argon flow rate on the migration behavior of bubbles and interface behavior between steel and slag was also investigated. The presented results indicate that the novel coupling process can significantly change the flow pattern in the stream zone of a tundish, prolong the average residence time of liquid steel, and reduce the dead fraction. A complete annular gas curtain is formed around the stopper rod of tundish. Under the action of drag force of liquid steel, a part of small bubbles enter the nozzle through the swirling grooves and gather toward the center of the nozzle by centripetal force. As the argon flow rate increases, the volume fraction of argon gas entering the nozzle increases, which enhances the swirl intensity and increases the concentration of bubbles in the nozzle. To avoid the formation of slag open eye in tundish, the argon flow rate should not exceed 8 L min−1.

关键词： Annular gas curtain swirling flow Tundish upper nozzle Multiphase flow Numerical simulation

Characteristics of annular impinging jets with/without swirling flow by short guide vanes

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Science China(Technological Sciences) 2011年第3期54卷 749-757页

作者： YANG HuiQun KIM TongBeum LU TianJian MOE Key Laboratory for Strength and Vibration School of Aerospace Xi'an Jiaotong University Xi'an 710049 China School of Mechanical Industrial and Aeronautical Engineering University of Witwatersrand Private Bag 3 Wits 2050 Johannesburg South Africa

Annular jets impinging on a uniformly heated flat plate with or without swirling flow by short guide vanes are experimentally characterized. With the Reynolds number fixed at a relatively low value, the variation of jet flow structures with impinging distance is characterized using the technique of particle image velocimetry (PIV). Correspondingly, the distributions of wall pressure and heat transfer on the plate are measured. At sufficiently large impinging distances, without swirling flow, the obtained flow and wall pressure/heat transfer data are consistent with the classical observation for a conventional annular impinging jet, showing the transition from annular impinging jet flow to single circular impinging jet-like flow. In contrast, no such transition occurs in the presence of flow turning by short guide vanes. At short and intermediate impinging distances, flow turning causes more non-uniform distributions of wall pressure and heat transfer on the target plate and the local heat transfer rates higher than those of the conventional annular jet. This is attributed to the vortical flow structures shed and convected downstream from the short guide vanes. In sharp contrast, at large impinging distances, the larger momentum loss due to flow turning results in lower heat transfer rates on the plate.

关键词： annular impinging jet flow structure swirling flow guide vanes wall heat transfer wall pressure

COMPUTATION OF RECIRCULATING swirling flow WITH THE GLM REYNOLDS STRESS CLOSURE

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Acta Mechanica Sinica 1994年第2期10卷 110-120页

作者：符松 Department of Engineering Mechanics Tsinghua University Beijing China 100084

A Reynolds stress closure based on the generalized Langevin model (GLM), developed by Haworth and Pope, is applied to the flow calculation with swirl-induced recirculation. The purpose of the work is to assess the performance of this model under the complex flow conditions caused by the presence of strong swirl which gives rise to both unconventional recirculation in the vicinity of the symmetry axis and strong anisotropy in the turbulence field. Comparison of the computational results are made both with the experimental data of Roback and Johnson and the computational results obtained with the typical isotropization of production model (IPM) and the k-∈ type Boussinesq viscosity model.

关键词： swirling flow turbulence modelling Reynolds stresses generalized Langevin model probability-density function

swirling flow and capillary diameter effect on the performance of an active dry powder inhalers

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Medicine in Novel Technology and Devices 2023年第2期18卷 215-225页

作者： Mohammad Hasan Taheri Nematollah Askari Yaning Feng Malikeh Nabaei Mohammad S.Islam Ali Farnoud Xinguang Cui Department of Mechanical Engineering Faculty of Imam KhomeiniBehshahr BranchTechnical and Vocational University(TVU)MazandaranIran School of Aerospace Engineering Huazhong University of Science and TechnologyWuhanChina Faculty of Biomedical Engineering Amirkabir University of Technology(Tehran Polytechnic)TehranIran School of Mechanical and Mechatronic Engineering University of Technology Sydney(UTS)15 BroadwayUltimoNSW2007Australia Computational Health Center Helmholtz MunichMunichGermany

For patients with lung disease,dry powder inhalers(DPI)are profoundly *** current study introduces and develops a series of dry powder inhalers(DPIs).A capsule-based(size 0)active DPI was *** study aims to investigate whether swirling flow and outlet capillary diameter(dc_out)affect the percentage of emitted doses(ED)released from the *** vanes were added to the capillary inlet to produce a swirling *** fluid dynamics(CFD)was applied to simulate the *** results were compared with previous in vitro and numerical studies to validate the *** on the derived results,the small swirl parameter(SP)enhances the secondary flow and recirculation *** increases the central jet flow,which increases the ED value by about 5–20%compared to no-swirl ***,as the airflow rate increases,the recirculation zone enlarges,vorticities become dominant,and asymmetrical flow patterns ***,ED%drops significantly(more than 50%).As d_(c_out)decreases,the vorticities around the outlet capillary become more potent,which is ***,the emptying of the capsule does not happen *** research provides a perspective on the device's design and DPI performance.

关键词： Computational fluid dynamics Dry powder inhalers swirling flow

Numerical simulation of swirling flow effect on the first stage vane film cooling distribution

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International Journal of Modeling, Simulation, and Scientific Computing 2016年第3期7卷 319-337页

作者： Hong Yin Electric Power Research Institute of Guangdong Power Grid Corporation Guangzhou Guangdong ProvinceP.R.China

In advanced gas turbine technology,lean premixed combustion is an effective strategy to reduce peak temperature and thus,NOX *** swirler is adopted to establish recirculation flow zone,enhancing mixing and stabilizing the ***,the swirling flow is dominant in the combustor flow field and has impact on the *** paper mainly investigates the swirling flow effect on the turbine first stage vane cooling system by conducting a group of numerical ***,the numerical methods of turbulence modeling using RANS and LES are *** computational model of one single swirl flow field is *** the RANS and LES results give reasonable recirculation zone *** comparing the velocity distribution,the RANS results generally match the experimental data but fail to at some local *** LES modeling gives better results and more detailed unsteady flow *** the second step,the RANS modeling is incorporated to investigate the vane film cooling performance under the swirling inflow boundary *** to the numerical results,the leading edge film cooling is largely altered by the swirling flow,especially for the swirl core-leading edge aligned *** to the pressure side,the suction side film cooling is more sensitive to the swirling ***,the film cooling jet is lifted and turned by the strong swirling flow.

关键词： Gas turbine swirling flow combustor simulator film cooling

An Investigation of the swirling flow and Heat Transfer in a Duct

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Journal of Thermal Science 1992年第1期1卷 19-23页

作者： TuJianping GuWeizao 等 InstituteofEngineeringThermophysics ChineseAcademyofSciencesBeijing100080China InstituteofEngineeri

This paper presents the results of experiments and numerical simulation of the turbulent swirling flow and heat transfer in a *** calculated results are in good agreement with data obtained by *** is found that the swirling flow promotes heat transfer to the wall of the duct;the swirl numbers are dependent upon the vane exit angles of the swirler,distance from the swirler and the duct Reynolds *** the decay of swirling flow in streamwise direction is related to local Reynolds numbers and is independent of the swirler exit *** swirl flow characteristics presented in this paper may be used for engineering purposes.

关键词： swirling flow duct flow heat transfer numerical simulation.