scholarly journals Active Control Experiments on High-speed Elevator Vibrations

2011 ◽  
Vol 21 (4) ◽  
pp. 325-332 ◽  
Author(s):  
Ki-Young Kim ◽  
Moon-K. Kwak ◽  
Kwang-Hyun Baek
Keyword(s):  
Active Control ◽  
High Speed

scholarly journals A Critical Review of Supersonic Flow Control for High-Speed Applications

2021 ◽  
Vol 11 (15) ◽  
pp. 6899
Author(s):  
Abdul Aabid ◽  
Sher Afghan Khan ◽  
Muneer Baig
Keyword(s):  
Supersonic Flow ◽  
Flow Control ◽  
Active Control ◽  
Critical Review ◽  
High Speed ◽  
Passive Control ◽  
Control Method ◽  
Sudden Expansion ◽  
Control Approach ◽  
Cost Efficient

In high-speed fluid dynamics, base pressure controls find many engineering applications, such as in the automobile and defense industries. Several studies have been reported on flow control with sudden expansion duct. Passive control was found to be more beneficial in the last four decades and is used in devices such as cavities, ribs, aerospikes, etc., but these need additional control mechanics and objects to control the flow. Therefore, in the last two decades, the active control method has been used via a microjet controller at the base region of the suddenly expanded duct of the convergent–divergent (CD) nozzle to control the flow, which was found to be a cost-efficient and energy-saving method. Hence, in this paper, a systemic literature review is conducted to investigate the research gap by reviewing the exhaustive work on the active control of high-speed aerodynamic flows from the nozzle as the major focus. Additionally, a basic idea about the nozzle and its configuration is discussed, and the passive control method for the control of flow, jet and noise are represented in order to investigate the existing contributions in supersonic speed applications. A critical review of the last two decades considering the challenges and limitations in this field is expressed. As a contribution, some major and minor gaps are introduced, and we plot the research trends in this field. As a result, this review can serve as guidance and an opportunity for scholars who want to use an active control approach via microjets for supersonic flow problems.

Hydraulic actuation system with active control for the lateral suspensions of high speed trains

2013 ◽  
Vol 20 (3) ◽  
pp. 236 ◽  
Author(s):  
Gualtiero Balossini ◽  
Laura Gastaldi ◽  
Giovanni Jacazio ◽  
Alberto Magnani
Keyword(s):  
Active Control ◽  
High Speed ◽  
Actuation System ◽  
High Speed Trains

scholarly journals A New Active Control Strategy for Pantograph in High-Speed Electrified Railways Based on Multi-Objective Robust Control

IEEE Access ◽  
2019 ◽  
Vol 7 ◽  
pp. 173719-173730 ◽  
Author(s):  
Jing Zhang ◽  
Hantao Zhang ◽  
Baolin Song ◽  
Songlin Xie ◽  
Zhigang Liu
Keyword(s):  
Robust Control ◽  
Active Control ◽  
Control Strategy ◽  
High Speed ◽  
Multi Objective ◽  
Active Control Strategy ◽  
Electrified Railways

scholarly journals Active Control of Contact Force for a Pantograph-Catenary System

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Jiqiang Wang
Keyword(s):  
Active Control ◽  
Contact Force ◽  
High Speed ◽  
Large Scale ◽  
Vibration Suppression ◽  
Numerical Study ◽  
Primary Objective ◽  
Geometric Framework ◽  
High Speed Trains ◽  
Catenary System

The performance of the high speed trains depends critically on the quality of the contact in the pantograph-catenary interaction. Maintaining a constant contact force needs taking special measures and one of the methods is to utilize active control to optimize the contact force. A number of active control methods have been proposed in the past decade. However, the primary objective of these methods has been to reduce the variation of the contact force in the pantograph-catenary system, ignoring the effects of locomotive vibrations on pantograph-catenary dynamics. Motivated by the problems in active control of vibration in large scale structures, the author has developed a geometric framework specifically targeting the remote vibration suppression problem based only on local control action. It is the intention of the paper to demonstrate its potential in the active control of the pantograph-catenary interaction, aiming to minimize the variation of the contact force while simultaneously suppressing the vibration disturbance from the train. A numerical study is provided through the application to a simplified pantograph-catenary model.

Research on MR Active Damping Control in Large-Diameter High-Speed Ball Mill

2010 ◽  
Vol 43 ◽  
pp. 110-113
Author(s):  
Qi Dong Chen ◽  
Yan Nian Rui ◽  
Xiao Mei Jiang ◽  
Ming Shen
Keyword(s):  
Computer Simulation ◽  
Active Control ◽  
Ball Mill ◽  
High Speed ◽  
Large Diameter ◽  
Mr Damper ◽  
Vibration Damping ◽  
Damping Control ◽  
Mr Damping ◽  
Control Principle

In this paper, MR damping mechanism is used to solve the vibration damping difficulties caused by the nonlinear vibration of ball mill. Dynamic model of MR Damper is constructed to design the damper of ball mill through research. Fuzzy control principle is adopted for active control of the MR damper and satisfactory results are obtained through computer simulation.

The Dynamic Analysis of an Energy Storage Flywheel System With Hybrid Bearing Support

2009 ◽  
Vol 131 (5) ◽  
Author(s):  
Hongchang Wang ◽  
Shuyun Jiang ◽  
Zupei Shen
Keyword(s):  
Control System ◽  
Energy Storage ◽  
Active Control ◽  
High Speed ◽  
Magnetic Bearing ◽  
Magnetic Bearings ◽  
Squeeze Film ◽  
Transmitted Force ◽  
Hybrid Bearing ◽  
Active Control System

Active magnetic bearings and superconducting magnetic bearings were used on a high-speed flywheel energy storage system; however, their wide industrial acceptance is still a challenging task because of the complexity in designing the elaborate active control system and the difficulty in satisfying the cryogenic condition. A hybrid bearing consisting of a permanent magnetic bearing and a pivot jewel bearing is used as the support for the rotor of the energy storage flywheel system. It is simple and has a long working life without requiring maintenance or an active control system. The two squeeze film dampers are employed in the flywheel system to suppress the lateral vibration, to enhance the rotor leaning stability, and to reduce the transmitted forces. The dynamic equation of the flywheel with four degrees of complex freedom is built by means of the Lagrange equation. In order to improve accuracy, the finite element method is utilized to solve the Reynolds equation for the dynamic characteristics of the squeeze film damper. When the calculated unbalance responses are compared with the test responses, they indicate that the dynamics model is correct. Finally, the effect of the squeeze film gap on the transmitted force is analyzed, and the appropriate gap should be selected to cut the energy loss and to control vibration of the flywheel system.

A Kind of Active Control Damping Shock Absorber

2014 ◽  
Vol 620 ◽  
pp. 511-515
Author(s):  
Han Song Yang ◽  
Peng Li ◽  
Li Zhi Gu ◽  
Hui Juan Guo
Keyword(s):  
Active Control ◽  
High Speed ◽  
Shock Absorber ◽  
Mechanical Energy ◽  
Control Variable ◽  
Suspension System ◽  
High Speed Train ◽  
Proportional Valve ◽  
The Road ◽  
Variable Damping

It is the main decrease press type used in high speed train of semi suspension system, as the parameter can not be regulated freely of the semi suspension system, to design a kind of damping shock absorber which with the sensitive and soft system are very important, this system which using of the Electro hydraulic proportional valve to regulation the safety valve, the guide valve and the damping force of shock absorber, get the recycle method of the hydraulic system from inner to outside, and also using the suspension active control variable damping shock absorber to detect the road, this device, in fact, by vibration, which let the valve move relation, turn the mechanical energy into hot and release outside, thus decrease the vibration. To design this variable damping shock absorber ,compared with the semi suspension system ,for it has the connect system and Electro hydraulic proportional valve, and with the road detectors, and various variable parameters, Which let the high speed train more stable and safety, overcome the short of parameter regulation for the semi-automatic suspension system.

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