scholarly journals Dynamic Simulation of a Warship Control Valve Based on a Mechanical-Electric-Fluid Cosimulation Model

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Jiazhen Han ◽  
Yudong Xie ◽  
Yong Wang ◽  
Qixian Wang
Keyword(s):  
Interaction Effect ◽  
Oscillation Amplitude ◽  
Flow Characteristics ◽  
Control Valve ◽  
Engineering Practice ◽  
Control Valves ◽  
Additional Load ◽  
Fluid Oscillation ◽  
Fluid Load ◽  
Stability Time

Control valves have an important function in the warship power system. In engineering practice, the fluid oscillation inside the control valve causes the additional load to the valve actuator. When the additional load is added to the original load of the valve, it is possible that the required driving force (or driving moment) of the valve is greater than the maximum force (or moment) output by the actuator, which may cause the abnormal stop of the actuator. Conventionally, the interaction effect of the valve mechanical and electric components on the valve chamber’s flow field cannot be considered in computational fluid dynamics (CFD) simulations, so the oscillating fluid loads cannot be accurately obtained. In order to solve this problem, the mechanical-electric-fluid integrated valve model, using the FLUENT and AMESim cosimulation method, was developed to embody the interaction effect between the components of each part of the control valve and exhibit the fluid oscillation during the operating process of the control valve. Compared with the pure software simulations, the unsteady flow characteristics and dynamic response of the actuator were synchronously obtained in this study, which accurately captured the sudden fluid loads required for further compensation. At the same time, the differences in performance of different valve plugs were compared. The stability time of the valve plug and oscillation amplitude of the unstable fluid loads were distinct for control valves with different flow characteristics. The results can aid in understanding the instability mechanism of the fluid load in the control valve better, which provides the calculation basis for compensating the additional load on the valve plug and improve the reliability of the control valve.

Control Valves: System Flow Characteristics and Controllability

1972 ◽  
Vol 5 (5) ◽  
pp. 181-187 ◽  
Author(s):  
D M Bishop
Keyword(s):  
Theoretical Basis ◽  
Flow Characteristics ◽  
Control Valve ◽  
Design Stage ◽  
Control Valves ◽  
Theoretical Examination ◽  
System Flow ◽  
Valve Size ◽  
The Relationship

A theoretical examination is made of the relationship between a control valve and the plant in which it is installed; the effect of valve size and characteristic on the relationship is described. From the theoretical basis, practical rules are devised for use at the design stage, also for later changes that may be necessary once the plant is in operation. Some well known practical difficulties are described, together with means of evading or overcoming them.

Experimental Study of Two-Phase Flow Induced by Cavitation Through a Safety Relief Valve

2013 ◽  
Author(s):  
Jorge Pinho ◽  
Patrick Rambaud ◽  
Saïd Chabane
Keyword(s):  
Local Minimum ◽  
Two Phase Flow ◽  
Flow Characteristics ◽  
Control Valve ◽  
Recovery Factor ◽  
Phase Flow ◽  
Relief Valve ◽  
Two Phase ◽  
Blow Down ◽  
Choked Flow

The goal of this study is to understand the behavior of a safety relief valve in presence of a two-phase flow induced by cavitation, in which the mass flux tends to be reduced. Two distinct safety relief valves are tested: an API 2J3 type and a transparent model based on an API 1 1/2G3 type. Instead of using a spring, the design of both valves allows the adjustment of the disk at any desired lift. Tests are conducted with water at ambient temperature. Results show a similar influence of cavitation on the flow characteristics of both valves. The liquid pressure recovery factor FL, which is normally used to identify a choked flow condition in a control valve, is experimentally determined in a safety relief valve. The existence of a local minimum located at a height position L/D = 0.14 indicates in this position, a change on the flow characteristics of both valves. It is verified that the existence of a local minimum in the liquid recovery factor is related to the minimum cross section of the flow, which does not remain constant for every lift positions. Furthermore, it is remarked that in the case of the 2J3 safety valve, the blow down ring adjustment has significant influence on the location of the minimum cross sections of the flow.

scholarly journals Fault Tolerant Control Design for Feedwater System

2021 ◽  
Author(s):  
Mohammed Eltayb
Keyword(s):  
Controller Design ◽  
Fault Tolerant ◽  
Control Valve ◽  
Fault Tolerant Control ◽  
Control Valves ◽  
Hardware Failure ◽  
Water Storage Tank ◽  
Level Sensor ◽  
On Line ◽  
Hardware Failures

Fault tolerant control (FTC) is essential nowadays in the automation industry. It provides a means for higher equipment availability. Fault in dynamical systems can occur due to the deviation of the system parameters from the normal operating range. Alternatively, it can be a structural change from the normal situation of continuous operation such as the blocking of an actuator due to the mechanical stiction. In this research project, a fault tolerant controller is designed with Matlab Simulink for a feedwater system. The feedwater system components are modified to work under embedded controller design with FTC attached to it. Feedwater systems usually consist of a de-aerator or simply a water storage tank, feedwater pumps, control valves, piping and support fitting elements such as chock valves, anges, hoses and relief valves, beside instrumentation devices like level transmitters, flow transmitters, pressure regulators. The faults are injected separately for each device. Fault diagnostic is used to detect and identify the faults by Limit-checking method. Then a controller is reconfigured to take the action of correcting the hardware failures in the control valve, level sensor, and feedwater pump. The simulation results revealed that the redundant components can take over and handle the process operation when the fault occurs at the duty components. Level sensors are set to work in on-line mode, while the control valves are set to work in off-line mode, due to the mechanical parts movement. Setting the control valves in on-line mode reduces the probability of valve stiction and elongates the component availability. The results reveal the operation of feedwater system is not stopped when a hardware failure takes place in all feedwater system major components. Moreover, the disturbances are not considered in this research as there are many control techniques that can be used to handle the disturbance in a robust way.

Investigation of Swirl Ratio Impact on In-Cylinder Flow in a SIDI Optical Engine

2015 ◽  
Author(s):  
Hanyang Zhuang ◽  
David L. S. Hung ◽  
Jie Yang ◽  
Shaoxiong Tian
Keyword(s):  
Flow Field ◽  
Soot Formation ◽  
Flow Characteristics ◽  
Control Valve ◽  
Exhaust Emission ◽  
Swirl Ratio ◽  
Optical Engine ◽  
Crank Angle ◽  
Cylinder Flow ◽  
Intake Swirl

Advanced powertrain technologies have improved engine performance with higher power output, lower exhaust emission, and better controllability. Chief among them is the development of spark-ignition direct-injection (SIDI) engines in which the in-cylinder processes control the air flow motion, fuel-air mixture formation, combustion, and soot formation. Specifically, intake air with strong swirl motion is usually introduced to form a directional in-cylinder flow field. This approach improves the mixing process of air and fuel as well as the propagation of flame. In this study, the effect of intake air swirl on in-cylinder flow characteristics was experimentally investigated. High speed particle image velocimetry (PIV) was conducted in an optical SIDI engine to record the flow field on a swirl plane. The intake air swirl motion was achieved by adjusting the opening of a swirl ratio control valve which was installed in one of the two intake ports in the optical engine. Ten opening angles of the swirl ratio control valve were adjusted to produce an intake swirl ratio from 0.55 to 5.68. The flow structures at the same crank angle degree, but under different swirl ratio, were compared and analyzed using proper orthogonal decomposition (POD). The flow dominant structures and variation structures were interpreted by different POD modes. The first POD mode captured the most dominant flow field structure characteristics; the corresponding mode coefficients showed good linearity with the measured swirl ratio at the compression stroke when the flow was swirling and steady. During the intake stroke, strong intake air motion took place, and the structures and coefficients of the first modes varied along different swirl ratio. These modes captured the flow properties affected by the intake swirl motion. Meanwhile, the second and higher modes captured the variation feature of the flow at various crank angle degrees. In summary, this paper demonstrated a promising approach of using POD to interpret the effectiveness of swirl control valve on in-cylinder swirl flow characteristics, providing better understanding for engine intake system design and optimization.

Tackling the Methane Quandary: Curbing Emissions from Control Valves

2021 ◽  
Author(s):  
Andrea Pacini ◽  
Stefano Rossini
Keyword(s):  
Oil And Gas ◽  
Petroleum Industry ◽  
Field Tests ◽  
Control Valve ◽  
Methane Emissions ◽  
Fugitive Emissions ◽  
Fugitive Emission ◽  
Control Valves ◽  
One Year ◽  
The One

Abstract In the wake of Eni's strategy to curb fugitive emissions - in particular methane – an innovative control valve (Clarke Shutter Valve) has been deployed and tested in an Italian Eni facility. This shutter type valve is capable of reducing the fugitive emissions by more than 90%, as well as greatly curbing purchase costs, thanks to an innovative design in bonnet and regulating mechanism. In order to assess the real potentiality of the innovation, four Fisher globe valves and one Fisher V-ball were substituted with the Shutter Valves on different hydrocarbon streams of the Trecate facility (Piedmont), in particular on streams containing oil, gas and corrosive fluids. The valves were monitored for more than a year and fugitive emissions tests have been performed to detect and estimate methane leak rates. Since this represented a first deployment of this technology in Europe, a thorough analysis and technology validation of the valves has been performed. A successful installation and start-up were performed in 3 days by Eni's staff at in February of 2020. The valves were fully operational after the installation and to date no issues have been reported. In order to monitor the valves performances of flow control, continuous data collection on each valve has been implemented, and the analysis performed showed that all valves behave correctly as to Eni's standards. A fugitive emission test that has been performed at the end of 2020 with a certified portable FID/PID analyzer displayed that no methane emissions were detected from the valves. Lastly the one year and half long technology validation concluded that the Shutter Valves are a valid technology for curbing methane emissions from the Oil and Gas plants, and that suggested to qualify the company as Eni partner for control valves. This deployment and field tests, as well as the technological assessment performed by Eni's professionals showed the potentiality of this new type of valves in reducing the methane emissions from the petroleum industry. Understanding the potentiality of intrinsically carbon neutral technology is a crucial step for the mitigation of greenhouse gases emissions and towards the creation of a more environmentally friendly industry.

Scaling of Steam Turbine Control Valve Guidance Pins

2021 ◽  
Vol 58 (4) ◽  
pp. 216-223
Author(s):  
A. Neidel ◽  
E. Cagliyan ◽  
B. Fischer
Keyword(s):  
Steam Turbine ◽  
Control Valve ◽  
Oxidation Products ◽  
Control Valves ◽  
Common Scale

Abstract Severe scaling caused the guiding pin of two control valves of a smaller industrial steam turbine to seize which thus led to a malfunction. The customer sought clarification on whether the oxidation products are really common scale. This could be confirmed.

scholarly journals Flow-Induced Vibration on the Control Valve with a Different Concave Plug Shape Using FSI Simulation

2019 ◽  
Vol 2019 ◽  
pp. 1-14
Author(s):  
Akram Zeid ◽  
Mohamed Shouman
Keyword(s):  
High Efficiency ◽  
Complex Structure ◽  
Three Dimensional ◽  
Flow Characteristics ◽  
Flow Simulation ◽  
Control Valve ◽  
Low Noise ◽  
Flow Induced Vibration ◽  
Nonlinear Characteristics ◽  
Flow Phenomena

Control valves have always been recognised as being among the most crucial control equipment, commonly utilised in versatile engineering applications. Hence, the need has arisen to identify the flow characteristics inside the valve, together with the incurred vibration induced as a result of the flow passing through the valve. Thanks to the tangible and fast progress made in the field of the flow simulation and numerical techniques, it has become possible to better observe the behavior of the flow passing inside a valve with view to examining its performance. Hence, the paper at hand is mainly concerned with introducing the modeling and simulation of a control valve. On the contrary, the flow system in a control valve is marked by a complex structure and nonlinear characteristics. The reasons for those qualities could be attributed to its construction as well as the fluid flow phenomena associated with it. It is especially for the sake of investigating and observing the flow characteristics, pertaining to a control valve equipped with different concave plug shapes and different openings, that the three-dimensional FSI simulation is conducted. In addition, it would be possible to make use of the obtained results relating to the three-dimensional analysis to achieve low noise and high efficiency improvement. Furthermore, all results will be validated on experimental grounds.

scholarly journals Local multiphase flow characteristics of a severe-service control valve

2020 ◽  
Vol 195 ◽  
pp. 107557
Author(s):  
D. Singh ◽  
A.M. Aliyu ◽  
M. Charlton ◽  
R. Mishra ◽  
T. Asim ◽  
...  
Keyword(s):  
Multiphase Flow ◽  
Flow Characteristics ◽  
Control Valve ◽  
Service Control

scholarly journals The Effect of Draft Ratio of Side-By-Side Barges on Fluid Oscillation in Narrow Gap

2020 ◽  
Vol 8 (9) ◽  
pp. 694
Author(s):  
Linfeng Chen ◽  
Xueshen Cao ◽  
Shiyan Sun ◽  
Jie Cui
Keyword(s):  
Resonant Frequency ◽  
Oscillation Amplitude ◽  
Numerical Results ◽  
Floating Body ◽  
Fluid Viscosity ◽  
Depth Range ◽  
Narrow Gap ◽  
Wave Tank ◽  
Fluid Oscillation ◽  
Viscous Fluid Model

In the present study, the effects of the draft ratio of the floating body on the fluid oscillation in the gap are investigated by using the viscous fluid model. Numerical simulations are implemented by coupling wave2Foam and OpenFOAM. The Volume of Fluid (VOF) model is used to capture the free surface waves. It is verified that the numerical results agree well with the experimental and other results. It is firstly found that, within the water depth range investigated in the present study, the depth of the wave tank has a significant effect on the numerical results. As the depth of the wave tank increases, the oscillation amplitude of the narrow-gap fluid largely decreases and the resonant frequency of the fluid oscillation in the narrow gap increases. The results also reveal that the draft ratio of floating bodies has a significant nonlinear influence on the resonant frequency and on the oscillation amplitude of the fluid in the narrow gap. With an increase in the draft of either the floating body on the wave side or the one on the back wave side, the resonant frequency decreases. The increase in the draft of the floating body on the wave side causes an increase in the reflection wave coefficient and leads to a drop in the fluid oscillation amplitude, and the increase in the draft of the floating body on the back wave side triggers a decrease in the reflection wave coefficient and results in an increase in the fluid oscillation amplitude. Meanwhile, the viscous dissipation induced by the fluid viscosity synchronously increases with the oscillation amplitude of the fluid in the increasing gap. Moreover, it is found that the draft ratio mainly affects the horizontal force of the floating body on the back wave side and that the highest calculated force increases with the draft ratio.

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