Significance of Proportional Valve Steady-State Characteristics

Abstract In this paper, two 3D CFD models of a load sensing proportional valve are contrasted. The models were developed with two different software, Simerics PumpLinx® and ANSYS Fluent®. In both cases the mesh was dynamically modified based on the fluid forces acting on the local compensator. In the former, a specific template for valves was used, in the latter a user-defined function was implemented. The models were validated in terms of flow rate and pressure drop for different positions of the main spool by means of specific tests. Two configurations were tested: with the local compensator blocked and free to regulate. The study has brought to evidence the reliability of the CFD models in evaluating the steady-state characteristics of valves with complex geometry.

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Simulation Research on the Basic Platform's Automatic Leveling System Based on SimHydraulics

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.345.99 ◽

2013 ◽

Vol 345 ◽

pp. 99-103 ◽

Cited By ~ 1

Author(s):

Yong Qing Chen ◽

Xin He Xu ◽

Hua Ling Zhu ◽

Shi De Ye ◽

Liang Tao Li

Keyword(s):

Control System ◽

Steady State ◽

System Design ◽

Simulation Study ◽

Pid Controller ◽

System Simulation ◽

Proportional Valve ◽

Simulation Research ◽

Adjustment Time ◽

Simulation Results

Based on the MATLAB/SimHydraulics toolbox, an automatic leveling system controlled by electro-hydraulic proportional valve was simulated and researched. With the help of Hydraulic components models in the SimHydraulics toolbox, the SimHydraulics Physical Network simulation and the Simulink control system simulation was integrated used, and the Simulink modules powerful numerical processing capability helped to improve the efficiency and accuracy of the system design. The simulation results showed that:The use of SimHydraulics toolbox on the simulation study of automatic leveling system controlled by electro-hydraulic proportional valve is feasible; The adjustment time of the automatic leveling system is short and the steady-state accuracy is high based on the PID controller.

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Research on Influence of Different types of Orifice on Axial Steady-state Flow Force in Cartridge Proportional Valve

International Journal of Fluid Power ◽

10.13052/ijfp1439-9776.2021 ◽

2019 ◽

Author(s):

Li Tan ◽

Haibo Xie ◽

Jianbin Liu ◽

Hanben Chen ◽

Huayong Yang

Keyword(s):

Steady State ◽

Test Bench ◽

Research Model ◽

Steady State Flow ◽

Cfd Simulations ◽

Proportional Valve ◽

State Flow ◽

Different Types ◽

Negative Effect ◽

Simulation Results

This article mainly investigates how orifice structure influences the characteristics of steady-state flow force. The research model of this paper is originated from a cartridge proportional valve. Firstly, predicting characteristics of the flow force working on poppet in different types of orifice through CFD simulations; secondly, several parameters of poppet and seat, which may affect the characteristics of flow force, are defined, a series of CFD calculations were conducted to find a rule how each parameter influences flow force; thirdly, according to the analysis, optimization of orifice structure parameters has been successfully realized. Finally, a test bench was established to validate the simulation results. The results show that the orifice type has a significant influence on flow force, which indicates that choosing certain type of orifice can effectively decrease the influence of flow force, and the negative effect of flow force can be reduced within an acceptable extent. Besides, the influence of orifice on pressure difference has been also taken into account. The experimental results agree well with the simulative one.

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Constant pressure control for steady — State pressure flow test of proportional valve

2017 4th International Conference on Systems and Informatics (ICSAI) ◽

10.1109/icsai.2017.8248269 ◽

2017 ◽

Author(s):

Jian Zhao ◽

Jian Jin ◽

KeLi Xing

Keyword(s):

Steady State ◽

Constant Pressure ◽

Pressure Control ◽

Proportional Valve ◽

Pressure Flow ◽

Flow Test ◽

State Pressure

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The Study of Opening Control Algorithm for Proportional Vales which are with Pressure Compensators

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.490-495.823 ◽

2012 ◽

Vol 490-495 ◽

pp. 823-827

Author(s):

Guo Ping Liu ◽

Jian Yu Yu ◽

Rong Hua Hu

Keyword(s):

Steady State ◽

Flow Control ◽

Linear Relationship ◽

Experimental Verification ◽

Electromagnetic Force ◽

Mechanical Model ◽

Control Algorithm ◽

Proportional Valve ◽

Precise Control ◽

Actual Point

It is essentially the precise control of opening that proportional valve flow control. This thesis establish mechanical model for proportional vales which with pressure compensators under the condition of steady-state, and experimental verification has been given, the result prove that electromagnetic force needs two mutations, while the normal PID can’t fulfill the requirements. The thesis has designed the algorithm of differential first PID, It is proved that this algorithm can fulfill the mutation of electromagnetic forces, We have achieved good linear relationship between setting point and actual point.

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Enhanced self-regulation nonlinear PID for industrial pneumatic actuator

International Journal of Electrical and Computer Engineering (IJECE) ◽

10.11591/ijece.v9i4.pp3015-3024 ◽

2019 ◽

Vol 9 (4) ◽

pp. 3015

Author(s):

S. N S. Salim ◽

M. F. Rahmat ◽

L. Abdullah ◽

S. A. Shamsudin ◽

M. Zainon ◽

...

Keyword(s):

Steady State ◽

System Performance ◽

Pid Controller ◽

Dead Zone ◽

Self Regulation ◽

Nonlinear Function ◽

Positioning System ◽

Proportional Valve ◽

Signal Error ◽

Steady State Performance

<p class="3Abstract">The present article describes the improvement of Self-regulation Nonlinear PID (SN-PID) controller. A new function is introduced to improve the system performance in terms of transient without affecting the steady state performance. It is used to optimize the nonlinear function available on this controller. The signal error is reprocessed through this function, and the result is used to tune the nonlinear function of the controller. Furthermore, the presence of the dead zone on the proportional valve is solved using Dead Zone Compensator (DZC). Simulations and experiments were carried out on the pneumatic positioning system. Comparisons between the existing methods were examined and successfully demonstrated.</p>

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Studies on Water in the Hydration Chamber of a Modified Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069715 ◽

1970 ◽

Vol 28 ◽

pp. 544-545

Author(s):

R. C. Moretz ◽

G. G. Hausner ◽

D. F. Parsons

Keyword(s):

Thin Film ◽

Thin Films ◽

Electron Microscope ◽

Steady State ◽

Room Temperature ◽

Small Mass ◽

Equilibrium Pressure ◽

Biological Objects ◽

Mechanical Pump ◽

Differential Pumping

Use of the electron microscope to examine wet objects is possible due to the small mass thickness of the equilibrium pressure of water vapor at room temperature. Previous attempts to examine hydrated biological objects and water itself used a chamber consisting of two small apertures sealed by two thin films. Extensive work in our laboratory showed that such films have an 80% failure rate when wet. Using the principle of differential pumping of the microscope column, we can use open apertures in place of thin film windows.Fig. 1 shows the modified Siemens la specimen chamber with the connections to the water supply and the auxiliary pumping station. A mechanical pump is connected to the vapor supply via a 100μ aperture to maintain steady-state conditions.

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Continuous hydrogenolysis of acetal-stabilized lignin in flow

Green Chemistry ◽

10.1039/d0gc02928a ◽

2021 ◽

Author(s):

Wu Lan ◽

Yuan Peng Du ◽

Songlan Sun ◽

Jean Behaghel de Bueren ◽

Florent Héroguel ◽

...

Keyword(s):

Steady State ◽

Challenges And Opportunities

We performed a steady state high-yielding depolymerization of soluble acetal-stabilized lignin in flow, which offered a window into challenges and opportunities that will be faced when continuously processing this feedstock.

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