Characteristic Analysis and Experiment of a Flow Distribution Valve

Comprehensive characteristics of a pneumatic underwater launching system were analyzed and the simulation was carried out by simulink. The components of the pneumatic underwater launching system were introduced, and the theoretical calculation formula for the system was derived. A rated pressure of 3.5MPa and 5MPa was offered in the numerical work. Analyses in different piston height show good behaviors: Proper increase of piston-initial accumulator pressure is beneficial to reduce hydrodynamic noise, choose the appropriate pressure of accumulator. The hydrodynamic noise of the system can be significantly reduced by optimizing the structure of the double-acting cylinder, increasing the height of the piston and improving the structure of the piston.

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A characteristic analysis of high pressure and high temperature 3-way ball valve

10.1063/1.4769027 ◽

2012 ◽

Author(s):

Joon Ho Lee ◽

Rock Won Jeon ◽

Si Pom Kim ◽

Jae Hun Lee ◽

Jae Hoon Lee

Keyword(s):

High Pressure ◽

High Temperature ◽

Ball Valve ◽

Characteristic Analysis

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Characteristic Analysis and Experiment of a Dynamic Flow Balance Valve

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/100/1/012107 ◽

2017 ◽

Vol 100 ◽

pp. 012107

Author(s):

Li Bin ◽

Guo Song ◽

Mao Xuyao ◽

Wu Chao ◽

Zhang Deman ◽

...

Keyword(s):

Dynamic Flow ◽

Characteristic Analysis ◽

Flow Balance

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A computational study of phase separation in polymer solutions under a double quench

10.32920/ryerson.14652258 ◽

2021 ◽

Author(s):

Ehsan Hosseini

Keyword(s):

Phase Separation ◽

Polymer Solution ◽

Spinodal Decomposition ◽

Computational Study ◽

Stable State ◽

Thermal Quenching ◽

Nucleation And Growth ◽

Two Dimensions ◽

Numerical Work ◽

Binary Polymer

Polymer-dispersed liquid crystals (PDLCs) are a relatively new class of materials used for many applications ranging from switchable windows to projection displays. PDLSs are formed by spinodal decomposition induced by thermal quenching or polymerization. The objective of the present study is to introduce a new mechanism of phase separation in a binary polymer solution and develop a mathematical model and computer simulation to describe the phase separation during the early and intermediate stages of nucleation and growth and spinodal decomposition induced by thermal double quenching. The growth equilibrium limits of phase separation as well as phase transition are calculated by taking into consideration the Flory-Huggins theory for the free energy of mixing. A two step quench is modeled using Cahn-Hilliard theory for asymmetric binary polymer solution which is quenched from a stable state in the one-phase region to a metastable region where nucleation and growth occurs. The solution is allowed to coarsen for different time periods before a second quench was applied to a point further inside the phase diagram. The numerical results in two dimensions replicate the experimental and numerical work that has been recently done and published.

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A computational study of phase separation in polymer solutions under a double quench

10.32920/ryerson.14652258.v1 ◽

2021 ◽

Author(s):

Ehsan Hosseini

Keyword(s):

Phase Separation ◽

Polymer Solution ◽

Spinodal Decomposition ◽

Computational Study ◽

Stable State ◽

Thermal Quenching ◽

Nucleation And Growth ◽

Two Dimensions ◽

Numerical Work ◽

Binary Polymer

Polymer-dispersed liquid crystals (PDLCs) are a relatively new class of materials used for many applications ranging from switchable windows to projection displays. PDLSs are formed by spinodal decomposition induced by thermal quenching or polymerization. The objective of the present study is to introduce a new mechanism of phase separation in a binary polymer solution and develop a mathematical model and computer simulation to describe the phase separation during the early and intermediate stages of nucleation and growth and spinodal decomposition induced by thermal double quenching. The growth equilibrium limits of phase separation as well as phase transition are calculated by taking into consideration the Flory-Huggins theory for the free energy of mixing. A two step quench is modeled using Cahn-Hilliard theory for asymmetric binary polymer solution which is quenched from a stable state in the one-phase region to a metastable region where nucleation and growth occurs. The solution is allowed to coarsen for different time periods before a second quench was applied to a point further inside the phase diagram. The numerical results in two dimensions replicate the experimental and numerical work that has been recently done and published.

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The Distribution Design and Dynamic Simulation Analysis of the Flow of the Transmission’s Cooling and Lubrication System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.633-634.1303 ◽

2014 ◽

Vol 633-634 ◽

pp. 1303-1310

Author(s):

Jing Ke Du ◽

Shu Han Wang ◽

Ting Bin Song ◽

Teng Teng Kang

Keyword(s):

Simulation Model ◽

Simulation Analysis ◽

System Modeling ◽

Flow Distribution ◽

Lubrication System ◽

System Flow ◽

Set Up ◽

Cooling And Lubrication ◽

Test Result ◽

New System

The bearing lubrication system flow distribution design of the transmission was realized with a new system modeling method, targeted at the problem of a certain type of transmission’s bearings’ sintering. The heat-generated model and the flow-required model of the bearings and the gears were set up, and the required lubrication flow was obtained. The simulation model of the system flow distribution was established, the simulation analysis toward the dynamic characteristic of the transmission’s lubrication flow’s distribution was performed, and the results of the simulation analysis and the test were analyzed comparatively. The result showed that the simulation model matched the test result well, proving the effectiveness and correctness of the model of the transmission’s flow distribution.

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Flow Maldistribution in a Simplified Plate Heat Exchanger Model - A Numerical Study

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.110-116.2529 ◽

2011 ◽

Vol 110-116 ◽

pp. 2529-2536 ◽

Cited By ~ 2

Author(s):

Nityanand Pawar ◽

R.S. Maurya

Keyword(s):

Heat Exchanger ◽

Uniform Distribution ◽

Numerical Study ◽

Flow Distribution ◽

Plate Heat Exchanger ◽

Design Parameters ◽

Process Equipment ◽

Numerical Work ◽

Plate Heat ◽

Flow Maldistribution

The performance of a plate heat exchanger (PHE) is severely influenced by non-uniform distribution of flow among its channels. Not only the PHEs, but many other process equipment needs uniform flow distribution for their optimum performance. Flow maldistribution (non-uniform distribution) is a common design problem which always puzzles process equipment designers. Being important design parameters, it has been investigated by several researchers and case based solution has been proposed and documented. Present numerical work is intended to target this aspect of the problem of PHEs but starts with a general investigation with simple multichannel geometry. The numerical setup consists of two headers having multiple channels for U-and Z-turn flow configuration under multichannel geometry and a simplified PHE for plate heat exchanger simulation. The problem has been investigated from hydrodynamic and thermodynamic view point. For hydrodynamic study, flow has been varied for Reynolds number 120 to 17600. It has been found that channel flow goes on reducing along downstream side. In thermal study the effect of wall temperature on air flow mal distribution has been investigated. Numerical results have been validated with the experimental results. Investigation reveals new features of flow mal-distribution which is helpful in better understanding of associated mal-distribution physics.

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A Three-Dimensional Transient Numerical Study of a Close-Coupled Catalytic Converter Internal Flow

Volume 2: Fora, Parts A and B ◽

10.1115/fedsm2007-37635 ◽

2007 ◽

Author(s):

Bassem H. Ramadan ◽

Russel L. Richmond

Keyword(s):

Velocity Profile ◽

Numerical Study ◽

Catalytic Converter ◽

Cone Angle ◽

Three Dimensional ◽

Flow Distribution ◽

Internal Flow ◽

Inlet Pipe ◽

Numerical Work ◽

Automotive Catalytic Converters

This study involves a numerical and experimental investigation of fluid flow in automotive catalytic converters. The numerical work involves using computational fluid dynamics (CFD) to perform three-dimensional calculations of turbulent flow in an inlet pipe, inlet cone, catalyst substrate (porous medium), outlet cone, and outlet pipe. The experimental work includes using hot-wire anemometry to measure the velocity profile at the outlet of the catalyst substrate, and pressure drop measurements across the system. Very often, the designer may have to resort to offset inlet and outlet cones, or angled inlet pipes due to space limitations. Hence, it is very difficult to achieve a good flow distribution at the inlet cross section of the catalyst substrate. Therefore, it is important to study the effect of the geometry of the catalytic converter on flow uniformity in the substrate. The analysis involved determining back pressure (BP) across the converter system for different monolith cell densities, mass flow rates, converter aspect ratio, inlet cone angle, and inlet pipe offset. The numerical results were used to study the velocity profile at the inlet to the substrate, and were verified with experimental measurements of velocity and BP.

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Study on the Stability of Micro-Area Sheet Resistance at Testing a Large Silicon Wafer when Probes Vacillated

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.303-306.399 ◽

2013 ◽

Vol 303-306 ◽

pp. 399-402 ◽

Cited By ~ 2

Author(s):

Xin Fu Liu ◽

Zhi Hui Zhu ◽

Ru Qing Zhang ◽

Run Li Zhang

Keyword(s):

Sheet Resistance ◽

Silicon Wafer ◽

Measurement Accuracy ◽

Probe Measurement ◽

Measurement Technology ◽

Calculation Formula ◽

Basic Principles ◽

Basic Concepts ◽

The Stability ◽

The Impact

This article briefly elaborated the basic concepts of the probe vacillated at testing a large silicon wafer with square four point probe equipment. The importance of the micro-area’s sheet resistance is discussed and the basic principles of four point probe measurement technology are analyzed. Some factors that affect the measurement accuracy are studied, and interference can be avoided while measuring and analyzing the impact on square four point probe measurement by probe vacillate. The calculation formula of the square micro-area probe measurement is deduced when probes vacillated discretionarily. At last, an experiment was made with a small wafer sample and accurate resistivity was gotten.

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