期刊文献+
任意字段
题名或关键词
题名
关键词
摘要
作者
第一作者
机构
刊名
分类号
参考文献
作者简介
基金资助
栏目信息
共找到10,563篇文章
< 1 2 … 250 >
每页显示 20 50 100
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
显示方式：
Flow control of a surface-mounted finite-length square cylinder using synthetic jets 认领 引用
1
作者 Shiqing Li Meihua Xia +3 位作者 Shuxuan Cai Yan Han Peng Hu Lingwei Zeng 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2026年第3期489-503,共15页
This paper studied the effect of synthetic jets on active flow control around a finite-length square cylinder using the large eddy simulation method.Based on the oncoming flow velocity(U∞)and the model width d,the... This paper studied the effect of synthetic jets on active flow control around a finite-length square cylinder using the large eddy simulation method.Based on the oncoming flow velocity(U∞)and the model width d,the corresponding Reynolds number is 2.78×104.We explored the impact of the momentum coefficient(Cμ)and the dimensionless jet frequency(f*)on a finite-length square cylinder’s aerodynamic forces and flow field characteristics.The square cylinder has an aspect ratio of 5,with one end mounted on a wall and the other end free.The synthetic jet outlet is deployed at the windward leading edge of the square cylinder.It is found that synthetic jets positioned at the top can effectively suppress the cylinder’s aerodynamic forces.Both the momentum coefficient and dimensionless jet frequency influence the control effectiveness.The maximum reductions in total mean drag coefficients(Cd,mean)and fluctuating lift coefficient(Cl,rms)are 4.01%and 50.7%,respectively.With synthetic jet control,the shear flow at the free end of the square cylinder is significantly suppressed,the separation bubble on the top surface disappears,the shear layer at the free end approaches the top surface of the square cylinder,and the turbulent kinetic energy near the free end is significantly enhanced.This study may offer valuable guidance for related engineering applications. 展开更多
关键词 Square cylinder Active flow control Synthetic jet LES
暂未订购 下载PDF
Improvement of Stability of a High-Loaded Axial Flow Compressor by a Combined Flow Control Method 认领 引用
2
作者 MENG Dejun YIN Haibao LIU Jie 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2026年第2期286-300,共15页
This study investigates a high⁃loaded axial compressor in which flow instabilities in the rotor and the stator occur almost concurrently.Under these conditions,conventional stability enhancement methods prove to be in... This study investigates a high⁃loaded axial compressor in which flow instabilities in the rotor and the stator occur almost concurrently.Under these conditions,conventional stability enhancement methods prove to be ineffective.The paper proposes a combined rotor-stator flow control technique.This study reveals that the flow field deterioration stems from combined flow blockage at the rotor tip region and the near-hub region of the stator.Research on flow control methods finds that self-recirculating casing treatment can effectively improve flow capacity in the rotor tip region,but simultaneously reduce flow capacity in the near-hub zone.This makes the hub flow field more susceptible to breakdown and ultimately triggers compressor instability.Thus,the self-recirculating casing treatment fails to enhance stall margin.By contrast,hub suction significantly improves the hub-region flow field.Yet without suppressing the rotor-tip flow blockage,it achieves limited stability enhancement.The integrated solution combining self-recirculating casing treatment with hub suction simultaneously addresses flow blockage at both the rotor tip and the stator near-hub regions.This combined flow control method delivers effective stability enhancement,achieving 6.78%increase in compressor stall margin. 展开更多
关键词 axial flow compressor high load stability combined flow control method flow mechanism
暂未订购 下载PDF
Integrated Equipment with Functions of Current Flow Control and Fault Isolation for Multiterminal DC Grids 认领 引用 被引量：1
3
作者 Shuo Zhang Guibin Zou 《Energy Engineering》 EI 2025年第1期85-99,共15页
The multi-terminal direct current(DC)grid has extinctive superiorities over the traditional alternating current system in integrating large-scale renewable energy.Both the DC circuit breaker(DCCB)and the current flow ... The multi-terminal direct current(DC)grid has extinctive superiorities over the traditional alternating current system in integrating large-scale renewable energy.Both the DC circuit breaker(DCCB)and the current flow controller(CFC)are demanded to ensure the multiterminal DC grid to operates reliably and flexibly.However,since the CFC and the DCCB are all based on fully controlled semiconductor switches(e.g.,insulated gate bipolar transistor,integrated gate commutated thyristor,etc.),their separation configuration in the multiterminal DC grid will lead to unaffordable implementation costs and conduction power losses.To solve these problems,integrated equipment with both current flow control and fault isolation abilities is proposed,which shares the expensive and duplicated components of CFCs and DCCBs among adjacent lines.In addition,the complicated coordination control of CFCs and DCCBs can be avoided by adopting the integrated equipment in themultiterminal DC grid.In order to examine the current flow control and fault isolation abilities of the integrated equipment,the simulation model of a specific meshed four-terminal DC grid is constructed in the PSCAD/EMTDC software.Finally,the comparison between the integrated equipment and the separate solution is presented a specific result or conclusion needs to be added to the abstract. 展开更多
关键词 Integrated equipment multiterminal direct current grid current flow control fault isolation
暂未订购 下载PDF
Nonlinear flow control mechanism of two flexible flaps with fluid-structure interaction 认领 引用
4
作者 Jiakun Han Chao Dong +1 位作者 Jian Zhang Gang Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2025年第2期116-131,共16页
The flow control at low Reynolds numbers is one of the most promising technologies in the field of aerodynamics,and it is also an important source of the innovation for novel aircraft.In this study,a new way of nonlin... The flow control at low Reynolds numbers is one of the most promising technologies in the field of aerodynamics,and it is also an important source of the innovation for novel aircraft.In this study,a new way of nonlinear flow control by interaction between two flexible flaps is proposed,and their flow control mechanism is studied employing the self-constructed immersed boundary-lattice Boltzmann-finite element method(IB-LB-FEM).The effects of the difference in material properties and flap length between the two flexible flaps on the nonlinear flow control of the airfoil are discussed.It is suggested that the relationship between the deformation of the two flexible flaps and the evolution of the vortex under the fluid-structure interaction(FSI).It is shown that the upstream flexible flap plays a key role in the flow control of the two flexible flaps.The FSI effect of the upstream flexible flap will change the unsteady flow behind it and affect the deformation of the downstream flexible flap.Two flexible flaps with different material properties and different lengths will change their own FSI characteristics by the induced vortex,effectively suppressing the flow separation on the airfoil’s upper surface.The interaction of two flexible flaps plays an extremely important role in improving the autonomy and adjustability of flow control.The numerical results will provide a theoretical basis and technical guidance for the development and application of a new flap passive control technology. 展开更多
关键词 Nonlinear flow control Flexible flap Fluid-structure interaction Flow separation IB-LB-FEM
暂未订购 下载PDF
Energy flow control of nanofluid-based direct absorption solar collectors with functional optical coatings for efficient solar harvesting 认领 引用
5
作者 XU Bing ZENG Rui-jing +1 位作者 ZHENG Nian-ben SUN Zhi-qiang 《Journal of Central South University》 SCIE EI CAS CSCD 2025年第8期3124-3135,共12页
The nanofluid-based direct absorption solar collector(NDASC)ensures that solar radiation passing through the tube wall is directly absorbed by the nanofluid,reducing thermal resistance in the energy transfer process.H... The nanofluid-based direct absorption solar collector(NDASC)ensures that solar radiation passing through the tube wall is directly absorbed by the nanofluid,reducing thermal resistance in the energy transfer process.However,further exploration is required to suppress the outward thermal losses from the nanofluid at high temperatures.Herein,this paper proposes a novel NDASC in which the outer surface of the collector tube is covered with functional coatings and a three-dimensional computational fluid dynamics model is established to study the energy flow distributions on the collector within the temperature range of 400-600 K.When the nanofluid’s absorption coefficient reaches 80 m-1,the NDASC shows the optimal thermal performance,and the NDASC with local Sn-In2O3 coating achieves a 7.8% improvement in thermal efficiency at 400 K compared to the original NDASC.Furthermore,hybrid coatings with Sn In2O3/WTi-Al2O3 are explored,and the optimal coverage angles are determined.The NDASC with such coatings shows a 10.22%-17.9% increase in thermal efficiency compared to the original NDASC and a 7.6%-19.5% increase compared to the traditional surface-type solar collectors,demonstrating the effectiveness of the proposed energy flow control strategy for DASCs. 展开更多
关键词 direct absorption solar collector nanofluid functional optical coatings energy flow control
暂未订购 下载PDF
Active flow control in aeronautic field and disease treatment in medical field 认领 引用
6
作者 Zhengyu ZUO Xin ZHANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2025年第11期1-4,共4页
Activeow control technology is a technique that controls the internaloweld of aircraft engines or theoweld around wings by means of disturbances induced by actuators,and adjusts the aerodynamic force and attitude of t... Activeow control technology is a technique that controls the internaloweld of aircraft engines or theoweld around wings by means of disturbances induced by actuators,and adjusts the aerodynamic force and attitude of the aircraft,so as to achieve the purposes of increasing lift,reducing drag,suppressing vibration and reducing noise.Hailed as an important source of innovative development for aircraft,this technology provides a new technical approach to solve the aerodynamic problems of aircraft,signicantly improve their comprehensive performance,break throughight boundaries,and promote disruptive innovation in the next generation of aircraft. 展开更多
关键词 aeronautical field disease treatment active flow control controls internaloweld adjusts aerodynamic force attitude aerodynamic problems activeow control technology aircraft engines
暂未订购 下载PDF
Flow Control in Six-Strand Billet Continuous Casting Tundish With Different Configurations 认领 引用 被引量：18
7
作者 ZHONG Liang-cai WANG Ming-an +2 位作者 CHEN Bo-yu WANG Can-rong ZHU Ying-xiong 《Journal of Iron and Steel Research International》 SCIE CAS 2010年第7期7-12,共6页
A 1∶2.5 scale tundish model was set up in laboratory for a six-strand billet continuous casting tundish with different configurations to investigate fluid flow characteristics under different operational conditions b... A 1∶2.5 scale tundish model was set up in laboratory for a six-strand billet continuous casting tundish with different configurations to investigate fluid flow characteristics under different operational conditions by measuring residence time distribution curves.It was found that minimum residence time,maximum concentration time and average residence time of the three strands on the same side of the tundish with the former configuration under normal operation,that is,six strands were open,were small and non-uniform and the tundish had large dead volume fraction.Vortexes easily formed on the liquid surface in the pouring zone of the tundish.The fluid flow characteristics in the tundish with the optimal turbulence inhibitor and baffles were improved and became less non-uniform among the strands.Vortexes were not found on the pouring zone surface in the optimal tundish.For non-normal operation,that is,one strand was close,it was important to choose which strand to be closed for maintaining flow characteristics of the rest two strands.It was found from this investigation that fluid flow characteristics in the optimal configuration tundish with closing strand 2 were better than those with closing strand 3 on the same side. 展开更多
关键词 billet continuous casting six-strand tundish flow control physical modeling operational mode
暂未订购 下载PDF
Optimization of flow control devices in a single-strand slab continuous casting tundish 认领 引用 被引量：17
8
作者 Ning Ding Yan-ping Bao +1 位作者 Qi-song Sun Li-feng Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2011年第3期292-296,共5页
The optimization of flow control devices in a single-slab continuous casting tundish was carried out by physical modeling, and the optimized scheme was presented. With the optimal tundish configuration, the minimum re... The optimization of flow control devices in a single-slab continuous casting tundish was carried out by physical modeling, and the optimized scheme was presented. With the optimal tundish configuration, the minimum residence time of liquid steel was increased by 1.4 times, the peak concentration time was increased by 97%, and the dead volume fraction was decreased by 72%. A mathematical model for molten steel in the tundish was established by using the fluid dynamics package Fluent. The velocity field, concentration field, and the resi-dence time distribution （RTD） curves of molten steel flow before and after optimization were obtained. Experimental results showed that the reasonable configuration with flow control devices can improve the fluid flow characteristics in the tundish. The results of industrial applica-tion show that the nonmetallic inclusion area ratio in casting slabs is decreased by 32% with the optimal tundish configuration. 展开更多
关键词 tundish flow control simulation optimization residence time
暂未订购 下载PDF
Application of Active Flow Control Technique for Gust Load Alleviation 认领 引用 被引量：11
9
作者 XU Xiaoping ZHU Xiaoping +1 位作者 ZHOU Zhou FAN Ruijun 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2011年第4期410-416,共7页
A new gust load alleviation technique is presented in this paper based on active flow control. Numerical studies are conducted to investigate the beneficial effects on the aerodynamic characteristics of the quasi ＂Gl... A new gust load alleviation technique is presented in this paper based on active flow control. Numerical studies are conducted to investigate the beneficial effects on the aerodynamic characteristics of the quasi ＂Global Hawk＂ airfoil using arrays of jets during the gust process. Based on unsteady Navier-Stokes equations, the grid-velocity method is introduced to simulate the gust influence, and dynamic response in vertical gust flow perturbation is investigated for the airfoil as well. An unsteady surface transpiration boundary condition is enforced over a user specified portion of the airfoil’s surface to emulate the time dependent velocity boundary conditions. Firstly, after applying this method to simulate typical NACA0006 airfoil gust response to a step change in the angle of attack, it shows that the indicial responses of the airfoil make good agreement with the exact theoretical values and the calculated values in references. Furthermore, gust response characteristic for the quasi ＂Global Hawk＂ airfoil is analyzed. Five kinds of flow control techniques are introduced as steady blowing, steady suction, unsteady blowing, unsteady suction and synthetic jets. The physical analysis of the influence on the effects of gust load alleviation is proposed to provide some guidelines for practice. Numerical results have indicated that active flow control technique,as a new technology of gust load alleviation, can affect and suppress the fluid disturbances caused by gust so as to achieve the purpose of gust load alleviation. 展开更多
关键词 active flow control gust response gust alleviation numerical simulation aerodynamics unsteady flow airfoil
暂未订购 下载PDF
MHD Flow Control of Oblique Shock Waves Around Ramps in Low-temperature Supersonic Flows 认领 引用 被引量：18
10
作者 Su Changbing Li Yinghong +3 位作者 Cheng Bangqin Wang Jian Cao Jun Li Yiwen 《Chinese Journal of Aeronautics》 SCIE EI CAS 2010年第1期22-32,共11页
This article is devoted to experimental study on the control of the oblique shock wave around the ramp in a low-temperature supersonic flow by means of the magnetohydrodynamic(MHD)flow control technique.The purpose of... This article is devoted to experimental study on the control of the oblique shock wave around the ramp in a low-temperature supersonic flow by means of the magnetohydrodynamic(MHD)flow control technique.The purpose of the experiments is to take advantage of MHD interaction to weaken the oblique shock wave strength by changing the boundary flow characteristics around the ramp.Plasma columns are generated by pulsed direct current(DC)discharge,the magnetic fields are generated by Nd-Fe-B rare-earth permanent magnets and the oblique shock waves in supersonic flow are generated by the ramp.The Lorentz body force effect of MHD interaction on the plasma-induced airflow velocity is verified through particle image velocimetry(PIV)measurements.The experimental results from the supersonic wind tunnel indicate that the MHD flow control can drastically change the flow characteristics of the airflow around the ramp and decrease the ratio of the Pitot pressure after shock wave to that before it by up to 19.66%,which leads to the decline in oblique shock wave strength.The oblique shock waves in front of the ramp move upstream by the action of the Lorentz body force.The discharge characteristics are analyzed and the MHD interaction time and consumed energy are determined with the help of the pulsed DC discharge images.The interaction parameter corresponding to the boundary layer velocity can reach 1.3 from the momentum conservation equation.The velocity of the plasma column in the magnetic field is much faster than that in the absence of magnetic field force.The plasma can strike the neutral gas molecules to transfer momentum and accelerate the flow around the ramp. 展开更多
关键词 aerospace propulsion system magnetohydrodynamic flow control plasma shock wave
暂未订购 下载PDF
Metro passenger flow control with station-to-station cooperation based on stop-skipping and boarding limiting 认领 引用 被引量：14
11
作者 姜曼 李海鹰 +2 位作者 许心越 徐仕鹏 苗建瑞 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第1期236-244,共9页
Metro passenger flow control problem is studied under given total inbound demand in this work,which considers passenger demand control and train capacity supply.Relevant connotations are analyzed and a mathematical mo... Metro passenger flow control problem is studied under given total inbound demand in this work,which considers passenger demand control and train capacity supply.Relevant connotations are analyzed and a mathematical model is developed.The decision variables are boarding limiting and stop-skipping strategies and the objective is the maximal passenger profit.And a passenger original station choice model based on utility theory is built to modify the inbound passenger distribution among stations.Algorithm of metro passenger flow control scheme is designed,where two key technologies of stopping-station choice and headway adjustment are given and boarding limiting and train stopping-station scheme are optimized.Finally,a real case of Beijing metro is taken for example to verify validity.The results show that in the three scenarios with different ratios of normal trains to stop-skipping trains,the total limited passenger volume is the smallest and the systematic profit is the largest in scenario 3. 展开更多
关键词 metro passenger flow control stop-skipping boarding limiting passenger original station choice
暂未订购 下载PDF
Improvement of tundish shape and optimization of flow control devices for sequence casting heavy steel ingots 认领 引用 被引量：11
12
作者 Guang-hua Wen Yong-feng Huang +1 位作者 Ping Tang Ming-mei Zhu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第1期15-20,共6页
The metallurgical effect of a round tundish used to cast heavy steel ingots in machine works at present was evaluated through water modeling experiments. The flow control devices of the improved oval tundish, which wa... The metallurgical effect of a round tundish used to cast heavy steel ingots in machine works at present was evaluated through water modeling experiments. The flow control devices of the improved oval tundish, which was used instead of the round tundish, had been optimized. The results show that the residence time of the round tundish is short, its inclusion removal efficiency is too low, and it has more dead zones and an unreasonable flow field. Compared with the round tundish, the improved oval tundish with the optimized weir and dam has a better effect： its minimum residence time is prolonged by 38.1 s, the average residence time is prolonged by 233.4 s, its dead volume fraction decreases from 26% to 15%, and the ratio of plug volume fraction to dead volume fraction increases from 0.54 to 1.27. The inclusion removal efficiency also increases by 17.5%. 展开更多
关键词 tundish steel ingots water modeling flow control devices inclusions
暂未订购 下载PDF
Recent progress of machine learning in flow modeling and active flow control 认领 引用 被引量：20
13
作者 Yunfei Li Juntao Chang +1 位作者 Chen Kong Wen Bao 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第4期14-44,共31页
In terms of multiple temporal and spatial scales, massive data from experiments, flow field measurements, and high-fidelity numerical simulations have greatly promoted the rapid development of fluid mechanics. Machine... In terms of multiple temporal and spatial scales, massive data from experiments, flow field measurements, and high-fidelity numerical simulations have greatly promoted the rapid development of fluid mechanics. Machine Learning(ML) provides a wealth of analysis methods to extract potential information from a large amount of data for in-depth understanding of the underlying flow mechanism or for further applications. Furthermore, machine learning algorithms can enhance flow information and automatically perform tasks that involve active flow control and optimization. This article provides an overview of the past history, current development, and promising prospects of machine learning in the field of fluid mechanics. In addition, to facilitate understanding, this article outlines the basic principles of machine learning methods and their applications in engineering practice, turbulence models, flow field representation problems, and active flow control. In short, machine learning provides a powerful and more intelligent data processing architecture, and may greatly enrich the existing research methods and industrial applications of fluid mechanics. 展开更多
关键词 Data-driven modeling Flow control Flow field kinematics Machine learning Neural networks-applications
暂未订购 下载PDF
Hypersonic flow control of shock wave/turbulent boundary layer interactions using magnetohydrodynamic plasma actuators 认领 引用 被引量：11
14
作者 Hao JIANG Jun LIU +2 位作者 Shi-chao LUO Jun-yuan WANG Wei HUANG 《Journal of Zhejiang University-SCIENCE A》 SCIE EI CAS CSCD 2020年第9期745-760,共16页
The effect of magnetohydrodynamic(MHD)plasma actuators on the control of hypersonic shock waveurbulent boundary layer interactions is investigated here using Reynolds-averaged Navier-Stokes calculations with low magne... The effect of magnetohydrodynamic(MHD)plasma actuators on the control of hypersonic shock waveurbulent boundary layer interactions is investigated here using Reynolds-averaged Navier-Stokes calculations with low magnetic Reynolds number approximation.A Mach 5 oblique shockurbulent boundary layer interaction was adopted as the basic configuration in this numerical study in order to assess the effects of flow control using different combinations of magnetic field and plasma.Results show that just the thermal effect of plasma under experimental actuator parameters has no significant impact on the flow field and can therefore be neglected.On the basis of the relative position of control area and separation point,MHD control can be divided into four types and so effects and mechanisms might be different.Amongst these,D-type control leads to the largest reduction in separation length using magnetically-accelerated plasma inside an isobaric dead-air region.A novel parameter for predicting the shock waveurbulent boundary layer interaction control based on Lorentz force acceleration is then proposed and the controllability of MHD plasma actuators under different MHD interaction parameters is studied.The results of this study will be insightful for the further design of MHD control in hypersonic vehicle inlets. 展开更多
关键词 Hypersonic Shock waveurbulent boundary layer interaction Magnetohydrodynamic(MHD) Flow control
暂未订购 下载PDF
Modulation of driving signals in flow control over an airfoil with synthetic jet 认领 引用 被引量：10
15
作者 Zhiyong LIU Zhenbing LUO +1 位作者 Qiang LIU Yan ZHOU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第12期3138-3148,共11页
A new skill of modulating driving signals of a synthetic jet with low frequency is introduced to enhance the control authority.Based on dynamic mesh technique,the effect of flow control over a NACA0015 airfoil with a ... A new skill of modulating driving signals of a synthetic jet with low frequency is introduced to enhance the control authority.Based on dynamic mesh technique,the effect of flow control over a NACA0015 airfoil with a Synthetic Jet Actuator(SJA)has been investigated.The SJA is located at x/c=10%,and two jet injection angles of 90°and 30°have been considered.Flow structures indicate that modulation with low frequency can reduce the dissipation rate of vortices after they shed off the surface.Thus aerodynamic performance of the airfoil could be improved.For the injection angle of 90°,modulation can increase the control authority of the SJA.Compared to the unmodulated case,increment of lift-to-drag ratio is up to 15%.The modulating frequency corresponding to the largest increment is FM+≈1.For the injection angle of 30°,improvement of aerodynamic forces positively relates to momentum coefficient of the SJA.Due to the decrease of effective momentum,modulation degrades the effect of flow control.The opposite responses to modulation are believed to have a relationship with the variation of primary control mechanism.When jet injection angle varies from 90°to 30°,the primary mechanism changes from the interaction of vortices and waves to the direct momentum addition.The skill of modulation of driving signals is very useful for applications of SJA. 展开更多
关键词 Airfoil Flow control Injection angle Modulation Momentum coefficient Synthetic jet
暂未订购 下载PDF
A Distributionally Robust Optimization Method for Passenger Flow Control Strategy and Train Scheduling on an Urban Rail Transit Line 认领 引用 被引量：10
16
作者 Yahan Lu Lixing Yang +4 位作者 Kai Yang Ziyou Gao Housheng Zhou Fanting Meng Jianguo Qi 《Engineering》 SCIE EI CAS CSCD 2022年第5期202-220,共19页
Regular coronavirus disease 2019(COVID-19)epidemic prevention and control have raised new require-ments that necessitate operation-strategy innovation in urban rail transit.To alleviate increasingly seri-ous congestio... Regular coronavirus disease 2019(COVID-19)epidemic prevention and control have raised new require-ments that necessitate operation-strategy innovation in urban rail transit.To alleviate increasingly seri-ous congestion and further reduce the risk of cross-infection,a novel two-stage distributionally robust optimization(DRO)model is explicitly constructed,in which the probability distribution of stochastic scenarios is only partially known in advance.In the proposed model,the mean-conditional value-at-risk(CVaR)criterion is employed to obtain a tradeoff between the expected number of waiting passen-gers and the risk of congestion on an urban rail transit line.The relationship between the proposed DRO model and the traditional two-stage stochastic programming(SP)model is also depicted.Furthermore,to overcome the obstacle of model solvability resulting from imprecise probability distributions,a discrepancy-based ambiguity set is used to transform the robust counterpart into its computationally tractable form.A hybrid algorithm that combines a local search algorithm with a mixed-integer linear programming(MILP)solver is developed to improve the computational efficiency of large-scale instances.Finally,a series of numerical examples with real-world operation data are executed to validate the pro-posed approaches. 展开更多
关键词 Passenger flow control Train scheduling Distributionally robust optimization Stochastic and dynamic passenger demand Ambiguity set
暂未订购 下载PDF
Flow Control for a Two-Stage Proportional Valve with Hydraulic Position Feedback 认领 引用 被引量：9
17
作者 He Wang Xiaohu Wang +1 位作者 Jiahai Huang Long Quan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第6期64-76,共13页
The current research mainly focuses on the flow control for the two-stage proportional valve with hydraulic position feedback which is named as Valvistor valve.Essentially,the Valvistor valve is a proportional throttl... The current research mainly focuses on the flow control for the two-stage proportional valve with hydraulic position feedback which is named as Valvistor valve.Essentially,the Valvistor valve is a proportional throttle valve and the flow fluctuates with the change of load pressure.The flow fluctuation severely restricts the application of the Valvistor valve.In this paper,a novel flow control method the Valvistor valve is provided to suppress the flow fluctuation and develop a high performance proportional flow valve.The mathematical model of this valve is established and linearized.Fuzzy proportional-integral-derivative(PID)controller is adopted in the closed-loop flow control system.The feedback is obtained by the flow inference with back-propagation neural network(BPNN)based on the spool displacement in the pilot stage and the pressure differential across the main orifice.The results show that inference with BPNN can obtain the flow data fast and accurately.With the flow control method,the flow can keep at the set point when the pressure differential across the main orifice changes.The flow control method is effective and the Valvistor valve changes from proportional throttle valve to proportional flow valve.For the developed proportional flow valve,the settling time of the flow is very short when the load pressure changes abruptly.The performances of hysteresis,linearity and bandwidth are in a high range.The linear mathematical model can be verified and the assumptions in the system modeling is reasonable. 展开更多
关键词 Flow control Proportional valve Hydraulic position feedback Back-propagation neural network
暂未订购 下载PDF
Experimental Study on Surface Dielectric Barrier Discharge Plasma Actuator with Different Encapsulated Electrode Widths for Airflow Control at Atmospheric Pressure 认领 引用 被引量：8
18
作者 齐晓华 杨亮 +3 位作者 闫慧杰 金英 滑跃 任春生 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第10期1005-1011,共7页
The surface dielectric barrier discharge （SDBD） plasma actuator has shown great promise as an aerodynamic flow control device. In this paper, the encapsulated electrode width of a SDBD actuator is changed to study t... The surface dielectric barrier discharge （SDBD） plasma actuator has shown great promise as an aerodynamic flow control device. In this paper, the encapsulated electrode width of a SDBD actuator is changed to study the airflow acceleration behavior. The effects of encapsulated electrode width on the actuator performance are experimentally investigated by measuring the dielectric layer surface potential, time-averaged ionic wind velocity and thrust force. Experimental results show that the airflow velocity and thrust force increase with the encapsulated electrode width. The results can be attributed to the distinct plasma distribution at different encapsulated electrode widths. 展开更多
关键词 atmospheric pressure discharge plasma surface dielectric barrier discharge（SDBD） flow control encapsulated electrode width Schlieren visualization
暂未订购 下载PDF
Active flow control of S-duct by plasma synthetic jet 认领 引用 被引量：5
19
作者 Ru-bing LIU Xiao-yin MEI +3 位作者 Sheng-hui XUE Yu-wen LU Zhe-zhe SU Qi LIN 《Journal of Zhejiang University-SCIENCE A》 SCIE EI CAS CSCD 2022年第8期652-668,共17页
Flow separation and secondary flow in the S-duct of an aircraft engine cause severe pressure loss and airflow distortion at the outlet,lowering engine performance.Herein,a serial two-electrode plasma synthetic jet(PSJ... Flow separation and secondary flow in the S-duct of an aircraft engine cause severe pressure loss and airflow distortion at the outlet,lowering engine performance.Herein,a serial two-electrode plasma synthetic jet(PSJ)actuator array is used to actively control the flow field in the duct and improve its characteristics.The results show that the PSJ significantly increases the wall pressure recovery coefficient,suppresses flow separation,and improves the outlet pressure distortion.The primary and secondary orders of the influencing factors are as follows:control position>jet momentum coefficient>excitation frequency>jet configuration.The best jet control position is near the separation location,and the best jet configuration is the‘Λ’configuration.The higher the jet momentum coefficient and excitation frequency,the better the flow control.The wall pressure coefficient increases by up to 127.8%,and the outlet steady pressure distortion index decreases by 9.15%.The control mechanism is the direct energy injection into the flow boundary layer through a high-speed jet and the indirect control effect of the induced streamwise vortex.On the one hand,the PSJ suppresses flow separation by improving the ability of the boundary layer to resist the inverse pressure gradient.On the other hand,it reduces pressure distortion by decreasing the intensity of the secondary flow and weakening the backflow.This study thus provides a new technology for the active control of the flow-field characteristics in an S-duct and has significance for guiding the application of synthetic jet technology in S-ducts. 展开更多
关键词 S-duct Flow control Plasma synthetic jet(PSJ) Flow separation Pressure distortion
暂未订购 下载PDF
Material flow control technology of ironmaking and steelmaking interface 认领 引用 被引量：7
20
作者 黄帮福 田乃媛 +1 位作者 施哲 丁跃华 《Journal of Central South University》 SCIE EI CAS 2014年第9期3559-3567,共9页
In order to achieve higher efficient cohesion match of procedure and equipment between ironmaking and steelmaking interface, the theory of multi-dimensional material flow control was applied to analyze torpedo ladle-i... In order to achieve higher efficient cohesion match of procedure and equipment between ironmaking and steelmaking interface, the theory of multi-dimensional material flow control was applied to analyze torpedo ladle-iron ladle transportation process between blast furnace and basic oxygen furnace. Moreover, basic parameters of material flow were analyzed and optimized, such as time, temperature and material quantity. Based on operating principles of material flow, control methods were optimized, such as product organization mode, scheduling discipline and scheduling plan of hot metal ladle. Finally, the material flow control technology of ironmaking and steelmaking interface was integrated. Satisfactory effects are obtained after applying the technology in practice. The total turnover number of torpedo ladle decreases from 20 to 18, the hot metal temperature of 1# BF torpedo ladle decreases from 36 °C to 19.5 °C, the hot metal temperature of 2# BF torpedo ladle decreases from 36.6 °C to 19.8 °C, the temperature drop of desulfurization hot metal decreases by 4 °C, and the temperature drop of non-desulfurization hot metal decreases by 2.8 °C. Furthermore, the ironmaking and steelmaking interface system will realize high-efficiency control by using this control technology. 展开更多
关键词 ironmaking and steelmaking interface torpedo ladle hot metal ladle material flow control control technology
暂未订购 下载PDF
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
上一页 1 2 … 250 下一页 到第 页
在线咨询 使用帮助 返回顶部 意见反馈