scholarly journals A Study on the Refrigerant Flow Characteristics Flowing into the Interior of the Electromagnetic Control Valve

2014 ◽  
Vol 16 (1) ◽  
pp. 1173-1178
Author(s):  
김대영 ◽  
Cho Haeng-Muk
Keyword(s):  
Flow Characteristics ◽  
Control Valve ◽  
Electromagnetic Control

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.

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.

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 A Two-Dimensional Study of Transonic Flow Characteristics in Steam Control Valve for Power Plant

2010 ◽  
Vol 3 (1) ◽  
pp. 58-66
Author(s):  
Koichi Yonezawa ◽  
Yoshinori Terachi ◽  
Toru Nakajima ◽  
Yoshinobu Tsujimoto ◽  
Kenichi Tezuka ◽  
...  
Keyword(s):  
Power Plant ◽  
Transonic Flow ◽  
Flow Characteristics ◽  
Control Valve ◽  
Two Dimensional

Pressure Fluctuations Around Steam Control Valve: Steam Experiments and CFD Calculations

2007 ◽  
Author(s):  
Ryo Morita ◽  
Fumio Inada
Keyword(s):  
Power Plant ◽  
Pressure Fluctuations ◽  
3D Structure ◽  
Flow Characteristics ◽  
Control Valve ◽  
Working Fluid ◽  
Complex Flow ◽  
Piping Systems ◽  
The Difference ◽  
Complex Flow Structure

In some cases, a steam control valve (figure 1) in a power plant causes large vibrations in piping systems that can be attributed to pressure fluctuations generated in the valve under the partial-valve-opening (middle-opening) condition. For the maintenance and the management of the plant, the valve system needs to be improved to prevent the onset of hydrodynamic instabilities. However, in the case of the steam control valve, it is difficult to understand the flow characteristics in detail experimentally because the flow around the valve has a complex 3D structure and becomes supersonic (M>1). For these reasons, the details of the flow around the valve are not fully understood before, and CFD simulations are required to understand the underlying complex flow structure associated with the valve. In our previous researches, a mechanism of the pressure fluctuations in the middle opening condition, named “rotating pressure fluctuations”, were clarified and a suppression shape were developed by experiments and CFD calculations. However, as we used air as a working fluid in our previous researches instead of steam that is used in the power plant, we couldn’t consider effects of condensation and difference of change of the state quantities between air and steam. In this report, we have conducted steam experiments and CFD calculations by original code to clarify the effects of the difference of the fluids. As a result, in the middle opening condition, we have observed spike-type pressure fluctuations and their rotation in the experiment, and valve-attached flow and local high-pressure region in the CFD result. These results indicate the pressure fluctuations observed in steam experiments and CFDs are the same as rotating pressure fluctuations observced in air researches.

scholarly journals Flow characteristics of control valve for different strokes

2016 ◽  
Vol 114 ◽  
pp. 02049 ◽  
Author(s):  
Jana Jablonská ◽  
Milada Kozubková
Keyword(s):  
Flow Characteristics ◽  
Control Valve

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.

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.

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