Analysis of a Pressure-Compensated Flow Control Valve

2004 ◽  
Vol 129 (2) ◽  
pp. 203-211 ◽  
Author(s):  
D. Wu ◽  
R. Burton ◽  
G. Schoenau ◽  
D. Bitner
Keyword(s):  
Pressure Drop ◽  
Flow Control ◽  
Flow Rate ◽  
Constant Pressure ◽  
Control Valve ◽  
Control Device ◽  
Operating Conditions ◽  
Flow Control Valve ◽  
Flow Control Device ◽  
Linearized Model

A pressure-compensated valve (PC valve) is a type of flow control device that is a combination of a control orifice and a compensator (often called a hydrostat). The compensator orifice modulates its opening to maintain a constant pressure drop across the control orifice. In other words, the PC valve is so designed that the flow rate through the valve is governed only by the opening of the control orifice and is independent of the total pressure drop across the valve. Because of the high nonlinearities associated with this type of valve, it is impossible, in practice, to design such a valve where the flow rate is completely unaffected by the pressure drop across the valve. In this paper, the effect of the nonlinearities on the performance of the PC valve is investigated. First, a generic nonlinear model of a PC valve is developed. Using this model, all possible operating conditions can be determined. Then a linearized model is developed and used to analyze the dynamic behavior of the PC valve. The model can then be used to evaluate and improve the design and operation of the valve for specific applications.

Analysis and Optimization Design of Pressure Compensated Flow Control Valves

2003 ◽  
Author(s):  
Duqiang Wu ◽  
Richard Burton ◽  
Greg Schoenau ◽  
Doug Bitner
Keyword(s):  
Pressure Drop ◽  
Flow Control ◽  
Flow Rate ◽  
Total Pressure ◽  
Optimization Design ◽  
Constant Pressure ◽  
Control Device ◽  
Operating Conditions ◽  
Flow Control Device ◽  
Linearized Model

A pressure compensated valve (PC valve) is a type of flow control device that is a combination of a control orifice and a compensator (often called a hydrostat). The compensator orifice modulates its opening to maintain a constant pressure drop across the control orifice. In other words, the PC valve is so designed that the flow rate through the valve is governed only by the opening of the control orifice and is independent of the total pressure drop across the valve. Because of the high non-linearities associated with this type of valve, it is impossible, in practice, to design such a valve where the flow rate is completely unaffected by the pressure drop across the valve. In this paper, the effect of the non-linerities on the performance of the PC valve is investigated. First, a generic non-liner model of a PC valve is developed. Using this model, all possible operating conditions can be determined. Then a linearized model is developed and used to analyze the dynamic behavior of the PC valve. The model can then be used to optimize the design and operation of the valve for specific applications.

Analysis and Modification of the Design of Fluid Power Control System for the Improvement of Product Quality

2013 ◽  
Author(s):  
Tahany W. Sadak ◽  
Taha E. Mkawee
Keyword(s):  
Flow Control ◽  
Flow Rate ◽  
System Performance ◽  
Dynamic Performance ◽  
Control Valve ◽  
Operating Conditions ◽  
Flow Control Valve ◽  
Supply Pressure ◽  
System Designs ◽  
Proportional Flow

This research investigation is focused on providing system performance under different operating conditions, with special focus on variations in the supply pressure. The investigations have been carried out for different system designs. The analysis of the results introduces the effect of system designs on its static and dynamic performance. Also, the investigations provide the effect of variations of system operating conditions and load value. A hydraulic system has been designed with variable velocity, pressure and load. The detailed examination has been carried out on a system that consists of a hydraulic power supply unit, control valves (pressure control valve, flow control valve, throttle valve and directional control valve). We have investigated the effect of adding a flow control valve (FCV) in the chosen circuit and also replacing the FCV with a proportional flow control valve (PFCV). In order to study the effect of this valve on system performance we examine the role of change of operating conditions and loading values on the system performance. Thus the displacement and speed of the piston of the hydraulic cylinder has been experimented under different values of supply pressure, flow rate, and load. We make this investigation to develop the performance evaluation by replacing the (FCV) by proportional flow control valve (PFCV) via position control so that one can achieve the static and dynamic performance of the system more accurate. Apparent improvement in flow rate ranges from 8% to 29.5% and dynamic response from 30 to 64%. The results reveal that this methodology allows one to achieve high quality of the product.

Design and Analysis of a Flow-Control Valve With Controllable Pressure Compensation Capability for Mobile Machinery

2021 ◽  
Author(s):  
Bo Wang ◽  
Yunwei Li ◽  
Long Quan ◽  
Lianpeng Xia
Keyword(s):  
Pressure Drop ◽  
Flow Control ◽  
Pressure Difference ◽  
Control Valve ◽  
Flow Control Valve ◽  
Continuous Control ◽  
Small Flow ◽  
Pressure Compensation ◽  
Force Compensation ◽  
Control Accuracy

Abstract There are the problems in the traditional pressure-compensation flow-control valve, such as low flow control accuracy, small flow control difficulty, and limited flow range. For this, a method of continuous control pressure drop Δprated (i.e. the pressure drop across the main throttling orifice) to control flow-control valve flow is proposed. The precise control of small flow is realized by reducing the pressure drop Δprated and the flow range is amplified by increasing pressure drop Δprated. At the same time, it can also compensate the flow force to improve the flow control accuracy by regulating the pressure drop Δprated. In the research, the flow-control valve with controllable pressure compensation capability (FVCP) was designed firstly and theoretically analyzed. Then the sub-model model of PPRV and the joint simulation model of the FVCP were established and verified through experiments. Finally, the continuous control characteristics of pressure drop Δprated, the flow characteristics, and flow force compensation were studied. The research results demonstrate that, compared with the traditional flow-control valve, the designed FVCP can adjust the compensation pressure difference in the range of 0∼3.4 MPa in real-time. And the flow rate can be altered within the range of 44%∼136% of the rated flow. By adjusting the compensation pressure difference to compensate the flow force, the flow control accuracy of the multi-way valve is improved, and the flow force compensation effect is obvious.

Development of Novel Particle Excitation Flow Control Valve for Stable Flow Characteristics

2016 ◽  
Vol 10 (4) ◽  
pp. 540-548 ◽  
Author(s):  
Daisuke Hirooka ◽  
◽  
Tomomi Yamaguchi ◽  
Naomichi Furushiro ◽  
Koichi Suzumori ◽  
...  
Keyword(s):  
Flow Control ◽  
Flow Rate ◽  
Flow Characteristics ◽  
Control Valve ◽  
Flow Control Valve ◽  
Different Types ◽  
Valve Opening ◽  
Working Principle ◽  
Stable Flow ◽  
Air Flow Control

The authors have previously developed a compact, light-weight air flow control valve, which realizes continuous flow control. The vibration produced by a piezoelectric device (PZT) was used to excite particles confined in a flow channel to control the valve opening for the developed control valve. Therefore, the voltage applied to the PZT can be changed to continuously control the flow rate. A new working principle was developed for the control valve to stabilize flow rate characteristics. Different types of particles were used to change the valve opening condition. A prototype was manufactured to demonstrate the effectiveness of the control valve.

An Investigation Into the Characteristics of a Two Dimensional “2D” Flow Control Valve

2001 ◽  
Vol 124 (1) ◽  
pp. 214-220 ◽  
Author(s):  
J. Ruan ◽  
R. Burton ◽  
P. Ukrainetz
Keyword(s):  
Flow Control ◽  
Flow Rate ◽  
Structural Parameters ◽  
Control Valve ◽  
Favorable Effect ◽  
Flow Control Valve ◽  
Two Dimensional ◽  
System Pressure ◽  
Hydrostatic Force ◽  
2D Flow

In hydraulic servo systems, a pilot stage is often used to reduce the influence of Bernoulli’s forces and frictional forces when trying to accurately position a spool. A unique pilot controlled valve (defined as a two dimensional or “2D” flow control valve), which utilizes both rotary and linear motions of a single spool, is presented. The rotary motion uses a spiral groove in the sleeve combined with high and low pressure holes on the spool land to control the pressure in the spool chamber, while the linear motion of the spool is actuated by a hydrostatic force. Both linear theory and numerical simulation are adopted in the investigation of the characteristics of the valve. A criterion for stability is established from a linearized model of the valve. The analysis establishes the effects that certain structural parameters have on the valve’s static and dynamic characteristics. Special experimental procedures were designed to obtain properties such as mechanical stiffness, leakage flow rate, and dynamic response under different structural parameters and system pressure. It was shown that the leakage through the spool-sleeve clearance had a favorable effect on the valve stability. Theoretical and experimental results show that it is necessary to establish a balance between the static and dynamic performance in establishing appropriate structural parameters. It is also shown that the 2D flow control valve can demonstrate a high speed of response, while maintaining the pilot flow rate at a low level.

Research Regarding Pressure Compensated Flow Control Valves

2015 ◽  
Vol 809-810 ◽  
pp. 992-997
Author(s):  
Irina Tiţa ◽  
Irina Mardare
Keyword(s):  
Power Systems ◽  
Flow Control ◽  
Hydraulic System ◽  
Block Diagram ◽  
Control Valve ◽  
Operating Conditions ◽  
Flow Control Valve ◽  
Constant Flow ◽  
Working Pressure ◽  
Displacement Pump

In fluid power systems, flow control may be done either with variable displacement pump or using variable orifice. In this paper is considered the second method for flow control. In a hydraulic system, working pressure is frequently variable and therefore the use of the method does not provide constant flow rates in all operating conditions. In order to keep a constant flow, if this is important in a certain case, the flow control must be accomplished using a pressure compensated flow control valve. In this paper are analyzed possible structural diagrams, mathematical model, block diagram and functional diagram for this kind of equipment. The influence of the spring compression is analyzed also. The diagrams proposed in the paper will be used for the study of a hydraulic system designated for applications with strict flow control. It will represent an important research instrument for such cases.

An Investigation Into the Characteristics of a “2D” Flow Control Valve

2000 ◽  
Author(s):  
J. Ruan ◽  
R. Burton ◽  
P. Ukrainetz
Keyword(s):  
Flow Control ◽  
Flow Rate ◽  
High Speed ◽  
Structural Parameters ◽  
Control Valve ◽  
Favorable Effect ◽  
Flow Control Valve ◽  
System Pressure ◽  
Hydrostatic Force ◽  
2D Flow

Abstract In hydraulic servo systems, a pilot stage is often used to reduce the influence of Bernoulli’s forces and frictional forces when trying to accurately position a spool. A unique pilot controlled valve, (defined as a “2D” flow control valve), which utilizes both rotary and linear motions of a single spool, is presented. The rotary motion uses a spiral groove in the sleeve combined with high and low pressure holes on the spool land to control the pressure in the spool chamber, while the linear motion of the spool is actuated by a hydrostatic force. Both linear theory and numerical simulation are adopted in the investigation of the characteristics of the valve. A criterion for stability is established from a linearized model of the valve. The analysis establishes the effects that certain structural parameters have on the valve’s static and dynamic characteristics. Special experimental procedures were designed to obtain properties such as mechanical stiffness, leakage flow rate, and dynamic response under different structural parameters and system pressure. It was shown that the leakage through the spool-sleeve clearance had a favorable effect on the valve stability. Theoretical and experimental results show that it is necessary to establish a balance between the static and dynamic performance in establishing appropriate structural parameters. It is also shown that the 2D flow control valve can demonstrate a high speed of response, while maintaining the pilot flow rate at a low level.

New Designs in Fuel Dispensing System to Control Maximum Flow of Volatile Liquid

2017 ◽  
Vol 868 ◽  
pp. 75-80
Author(s):  
Ya Jun Liu ◽  
Shu Yan Zhan ◽  
Jia Kun Ye ◽  
Wen Hua Xie
Keyword(s):  
Flow Control ◽  
Flow Rate ◽  
Oil And Gas ◽  
Control Valve ◽  
Maximum Flow ◽  
Control Mode ◽  
Theoretical Research ◽  
Flow Control Valve ◽  
Cavitation Phenomenon ◽  
Volatile Liquid

The dispenser is a fuel pumping and measurement device used in the service station. During the refueling process of volatile liquid, the cavitation phenomenon occur easily due to the large flow rate. The serious cavitation will not only reduce the pumping efficiency, produce loud work noise, but also aggravate the pollution of oil and gas and the energy consumption of the system. Therefore, it is necessary to control the maximum flow rate of the pump. Based on this problem, this paper firstly designs a new flow control valve, and a method of mathematical modeling is proposed to analyze the flow field distribution and the working principle of the whole device based on Euler equation and Bernoulli equation. Then we combine this new hydraulic device to the variable frequency dispenser, a new design of the dispenser structure and a control mode of the maximum flow are proposed. The theoretical research shows that the maximum flow can be limited by optimizing diameter ratio of that flow control valve.

Improving the Performance of a Two Way Flow Control Valve, Using a 3D CFD Modeling

2014 ◽  
Author(s):  
Emma Frosina ◽  
Adolfo Senatore ◽  
Dario Buono ◽  
Michele Pavanetto ◽  
Micaela Olivetti ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Flow Control ◽  
Fluid Dynamic ◽  
Control Valve ◽  
Operating Conditions ◽  
Cfd Modeling ◽  
Flow Control Valve ◽  
Development Costs ◽  
Definition Of ◽  
The Mathematical Model

The paper introduces a methodology aimed to optimize the performance of hydraulic components; in particular the design of a new two way flow control valve studying the valve internal fluid-dynamic behavior will be introduced. The methodology is based on the definition of a CFD tridimensional fluid-dynamic model. In fact, the model can help engineers to develop the best geometry, to optimize the valve performance, reducing the prototyping requirement and finally the time-to-market and, consequently, the development costs. At first, the original spool internal geometry has been evaluated and studied to tune the mathematical model and to validate it comparing its results with the data obtained through an experimental campaign. Then, the same approach has been applied to investigate several different internal spool geometries to define the best one in all operating conditions. A limited number of solutions have been prototyped and tested to verify the mathematical model predictions, in order to find the best configuration whose performances are consistent with the assigned objective for the component.

scholarly journals Development of Virtual Flow Sensor using Artificial Neural Networks

2019 ◽  
Vol 9 (2) ◽  
pp. 4081-4087
Keyword(s):  
Neural Networks ◽  
Artificial Neural Networks ◽  
Pressure Drop ◽  
Flow Control ◽  
Flow Rate ◽  
Functional Relation ◽  
Control Valve ◽  
Flow Sensor ◽  
Control Element ◽  
Artificial Neural

In this paper, a virtual flow sensor using artificial neural networks (ANN) is proposed to improve the efficiency of an industrial flow control loops. In conventional flow-control loop, flow meters used for sensing flow rate in the feedback path cause pressure drop in the flow. This may increase the energy usage for propelling the fluid. The functional relation between the flow rate and the physical properties of the flow through the final control element such as control valve is known and the said properties namely pressure drop, temperature, and valve position are yielded from an experimental set-up. These properties are used as training data for ANN models to yield the fluid flow rate through the control valve. Here, the ANN acts as a virtual flow sensor. The feasibility of the proposed methodology is validated by using real measurement of flow and used them to model virtual flow sensor using the multi-layer perceptron artificial neural networks (MLP-ANN) with back propagation (BP) algorithm. Moreover, its practical proof of concept is demonstrated by implementing the trained MLP-ANN on a Spartan-3E-starter Field Programmable Gate Array (FPGA) unit through a hardware co-simulation.

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