scholarly journals Dynamic Performance Analysis of a Compact Annular-Radial-Orifice Flow Magnetorheological Valve and Its Application in the Valve Controlled Cylinder System

Actuators ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 104
Author(s):  
Guoliang Hu ◽  
Feng Zhou ◽  
Mingke Liao ◽  
Lifan Yu
Keyword(s):  
Pressure Drop ◽  
Dynamic Performance ◽  
Response Characteristic ◽  
Applied Current ◽  
Damping Force ◽  
Orifice Flow ◽  
Working Principle ◽  
Dynamic Performance Analysis ◽  
Magnetorheological Valve ◽  
Key Parameter

A compact annular-radial-orifice flow magnetorheological (MR) valve with variable radial damping gaps was proposed, and its structure and working principle were also described. Firstly, a mathematical model of pressure drop was established as well to evaluate the dynamic performance of the proposed MR valve. Sequentially, the pressure drop distribution of the MR valve in each flow channel was simulated and analyzed based on the average magnetic flux densities and yield stress along the damping gaps through finite element method. Further, the experimental test rig was setup to explore the pressure drop performance and the response characteristic of the MR valve and to investigate dynamic performance of the valve controlled cylinder system under different radial damping gaps. The experimental results revealed that the pressure drop and response time of the MR valve augment significantly with the increase of applied current and decrease of the radial damping gap. In addition, the damping force of the proposed MR valve controlled cylinder system decrease with the increase of the radial damping gap. The maximum damping force can reach about 4.72 kN at the applied current of 2 A and the radial damping gap of 0.5 mm. Meanwhile, the minimum damping force can reach about 0.67 kN at the applied current of 0 A and the radial damping gap of 1.5 mm. This study clearly demonstrates that the radial damping gap of the MR valve is the key parameter which directly affects the dynamic characteristics of the valve controlled cylinder system, and the proposed MR valve can meet the requirements of different working conditions by changing the radial damping gaps.

scholarly journals Damping Performance Analysis of Magnetorheological Damper Based on Multiphysics Coupling

Actuators ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 176
Author(s):  
Guoliang Hu ◽  
Lifan Wu ◽  
Yingjun Deng ◽  
Lifan Yu ◽  
Bin Luo
Keyword(s):  
Flow Field ◽  
Field Model ◽  
Dynamic Performance ◽  
Mr Damper ◽  
Experimental Results ◽  
Structural Stress ◽  
Applied Current ◽  
Damping Force ◽  
Multiphysics Coupling ◽  
Simulation Results

Magnetorheological (MR) damper performance is evaluated only by single-field analysis in the design process, which can easily lead to larger design errors. Based on this, a simulation method of MR damper considering multiphysics coupling was proposed. According to a certain automobile shock absorber requirement, an MR damper suitable for automobile suspension was designed. The mechanical model, electromagnetic field model, flow field model, and structural stress field model of the MR damper were deduced and established. To investigate the damping performance of the MR damper more accurately, the multiphysics coupling simulation model was established by COMSOL software, and coupling analysis of the electromagnetic field, flow field, and structural stress field was also carried out. The static magnetic field characteristics, dynamic flow field characteristics, stress distribution, and dynamic performance of the proposed MR damper under the action of multiphysics coupling were obtained. The simulation results show that the damping force is 1134.6 N, and the damping adjustable coefficient is 9.1 at an applied current of 1.4 A. A test system was established to analyze the dynamic performance of the MR damper, and the simulation results were compared with the experimental results. The results show that the simulated and experimental results have the same change rule. Moreover, the damping force increases with the applied current, and different external excitations have little effect on the damping force. The damper can output appropriate damping force and has a wide adjustable damping range. The experimental results illustrate that the damping force is 1200.0 N, and the damping adjustable coefficient is 10.1 when the current is 1.4 A. The error between simulation and experiment of the damping force and damping adjustable coefficient is only 5.5% and 9.9%, respectively.

Modeling Planar Joints With Clearance Between the Guide and Roller in Mechanisms

2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Yunkai Gao ◽  
Yuexing Duan ◽  
James Yang ◽  
Zhe Yuan ◽  
Chao Ma
Keyword(s):  
Experimental Data ◽  
Contact Force ◽  
Convex Surface ◽  
Dynamic Performance ◽  
Kinematic Model ◽  
Force Model ◽  
Damping Force ◽  
Contact Force Model ◽  
Dynamic Performance Analysis ◽  
Rms Errors

Abstract In mechanisms, the guide and roller form joints with clearance and the roller may make contact with the convex surface or concave surface of the guide. Correctly modeling this type of joint is critical in a mechanism's dynamic performance analysis. This paper proposes a contact kinematic model and a hybrid contact force model for the planar joint and investigates both the convex and concave contact cases. The contact kinematic model is derived from the relative motion between the guide and roller and the hybrid contact force model consists of an elastic force and a damping force. The sliding door mechanism is used as an illustrative example to demonstrate the proposed models. Experimental data are collected for a vehicle's sliding door mechanism. Results show that the proposed models are effective and the simulation results match the general trend of experimental data based on RMS errors.

scholarly journals Optimal Design and Performance Analysis of Radial MR Valve with Single Excitation Coil

Actuators ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 34
Author(s):  
Guoliang Hu ◽  
Feng Zhou ◽  
Lifan Yu
Keyword(s):  
Pressure Drop ◽  
Magnetic Flux ◽  
Internal Structure ◽  
Total Pressure ◽  
Damping Force ◽  
Flux Lines ◽  
Total Pressure Drop ◽  
Excitation Coil ◽  
Static Performance ◽  
And Performance

The main issue addressed in this paper involves the magnetorheological (MR) valve increasing the pressure drop by changing the internal structure, which leads to the increase of dimension sizes and the easy blocking of the internal channel. Optimizing the design of the traditional radial MR valve without changing the internal structure and whole dimension size is indispensable. Firstly, a radial MR valve with single excitation coil was proposed. The mathematical models of the field-dependent pressure drop and viscosity pressure drop in fluid flow channels were deduced, and the calculation formula of pressure drop was also established. Then, ANSYS software was used to simulate and analyze the distributions of the magnetic flux lines and magnetic flux densities of the proposed radial MR valve. Subsequently, the radial MR valve was simulated and analyzed by using the ANSYS first-order and zero-order simulation tools. In addition, the experimental test bench of the proposed MR valve was setup, the static performance of pressure drop was tested, and the change of pressure drop of the optimal radial MR valve under different loads was studied, furthermore, the response time with current of the initial and optimal radial MR valve were also investigated. Finally, the dynamic performances of the optimal radial MR valve controlled cylinder system under different currents, frequencies and amplitudes were tested, respectively. The experimental results indicate that the total pressure drop of the initial valve is 1.842 MPa when the applied current is 1.8 A, and the total pressure drop of the optimal valve is 2.58 MPa, the increase is 40.07%. Meanwhile, the maximum damping force of the optimal radial MR valve controlled cylinder system can reach about 3.6 kN at the current of 1.25 A, which shows a better optimization effect of the optimal radial MR valve.

scholarly journals Off-Design Dynamic Performance Analysis of a Solar Aided Coal-Fired Power Plant

Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2950
Author(s):  
Vinod Kumar ◽  
Liqiang Duan
Keyword(s):  
Power Plant ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Thermal Efficiency ◽  
Dynamic Performance ◽  
Feed Water ◽  
Saving Rate ◽  
Coal Consumption ◽  
Dynamic Performance Analysis

Coal consumption and CO2 emissions are the major concerns of the 21st century. Solar aided (coal-fired) power generation (SAPG) is paid more and more attention globally, due to the lesser coal rate and initial cost than the original coal-fired power plant and CSP technology respectively. In this paper, the off-design dynamic performance simulation model of a solar aided coal-fired power plant is established. A 330 MW subcritical coal-fired power plant is taken as a case study. On a typical day, three various collector area solar fields are integrated into the coal-fired power plant. By introducing the solar heat, the variations of system performances are analyzed at design load, 75% load, and 50% load. Analyzed parameters with the change of DNI include the thermal oil mass flow rate, the mass flow rate of feed water heated by the solar energy, steam extraction mass flow rate, coal consumption, and the plant thermal efficiency. The research results show that, as DNI increases over a day, the coal saving rate will also increase, the maximum coal saving rate reaches up to 5%, and plant thermal efficiency reaches 40%. It is analyzed that the SAPG system gives the best performance at a lower load and a large aperture area.

Finite Element Analysis and Optimization of Long-Span Gantry NC Machining Center Structure

2011 ◽  
Vol 346 ◽  
pp. 379-384
Author(s):  
Shu Bo Xu ◽  
Yang Xi ◽  
Cai Nian Jing ◽  
Ke Ke Sun
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Design Method ◽  
Dynamic Performance ◽  
Plate Thickness ◽  
Element Model ◽  
Wall Structure ◽  
Characteristic Analysis ◽  
Element Analysis ◽  
Dynamic Performance Analysis

The use of finite element theory and modal analysis theory, the structure of the machine static and dynamic performance analysis and prediction using optimal design method for optimization, the new machine to improve job performance, improve processing accuracy, shorten the development cycle and enhance the competitiveness of products is very important. Selected for three-dimensional CAD modeling software-UG NX4.0 and finite element analysis software-ANSYS to set up the structure of the beam finite element model, and then post on the overall structure of the static and dynamic characteristic analysis, on the basis of optimized static and dynamic performance is more superior double wall structure of the beam. And by changing the wall thickness and the thickness of the inner wall, as well as the reinforcement plate thickness overall sensitivity analysis shows that changes in these three parameters on the dynamic characteristics of post impact. Application of topology optimization methods, determine the optimal structure of the beam ultimately.

Dynamic Performance Analysis on High-Speed Railway Continuous Girder Bridge

2011 ◽  
Vol 280 ◽  
pp. 186-190
Author(s):  
Shou Tan Song ◽  
Ji Wen Zhang ◽  
Xin Yuan
Keyword(s):  
High Speed ◽  
Moving Load ◽  
Damping Ratio ◽  
Dynamic Performance ◽  
Wheel Load ◽  
Dynamic Coefficients ◽  
Bridge Structures ◽  
Continuous Girder Bridge ◽  
Girder Bridge ◽  
Dynamic Performance Analysis

The dynamic performance of continuous girder under the train in a series of speed is studied through examples, and the main conclusions are given in the following. The resonance mechanism of continuous girder is similar to simply supported beam. The vehicle wheel load forms regular moving load series, which induces periodical action and resonance of the bridge. The damping ratio of bridge itself has less effect on the amplitude at the loading stage, but significant effects appear when the load departs from the bridge. The count of continuous spans also has less impact on the dynamic coefficients, so three continuous spans can be adopted for calculation and analysis. Span and fundamental frequency have significant influence on dynamic coefficients of bridge structures. To extend the span of the bridge structure can reduce the dynamic coefficient while keeping its frequency invariant. The fundamental frequencies of different bridges are corresponding to certain resonant speeds, which calls for the attention in the design.

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