Study on Flow Patterns and Separation Performance of Liquid-Gas Separator Units

2014 ◽  
Vol 1008-1009 ◽  
pp. 919-926
Author(s):  
Xue Qing Chen ◽  
Lei Tong
Keyword(s):  
High Speed ◽  
Separation Efficiency ◽  
Flow Patterns ◽  
Test System ◽  
High Speed Photography ◽  
Separation Performance ◽  
Discharge Process ◽  
Experimental Conditions ◽  
Operation Conditions ◽  
Gas Separator

Three liquid-gas separator units were designed and manufactured from transparent acrylic resin based on the concept of a new kind of validated high performance condenser. The separator units had different spaces between baffle and outlet arm or different header diameters. A visualization cold state test system was set up to explore the basic principle of liquid-gas separation and liquid discharge process, using air and water as the working fluids. Four kinds of liquid flow patterns were observed by the liquid staining and high-speed photography at inlet air superficial velocities from 1m/s to 15m/s and water superficial velocities from 0.0015m/s to 0.06m/s. The effects of operation conditions and structure parameters on the separation efficiency of the liquid-gas separator units were investigated. The results showed that under the experimental conditions, the separation efficiency was more than 70%, the separation efficiency could be improved by increasing the space between baffle and outlet arm as well as the header diameter.

Field testing CFD-based predictions of storage chamber gross solids separation efficiency

1999 ◽  
Vol 39 (9) ◽  
pp. 161-168 ◽  
Author(s):  
Virginia R. Stovin ◽  
Adrian J. Saul ◽  
Andrew Drinkwater ◽  
Ian Clifforde
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Settling Velocity ◽  
Separation Efficiency ◽  
Flow Patterns ◽  
Total Efficiency ◽  
Separation Performance ◽  
Storage Chamber ◽  
Solids Separation ◽  
Simulated Flow

The use of computational fluid dynamics-based techniques for predicting the gross solids and finely suspended solids separation performance of structures within urban drainage systems is becoming well established. This paper compares the result of simulated flow patterns and gross solids separation predictions with field measurements made in a full size storage chamber. The gross solids retention efficiency was measured for six different storage chambers in the field and simulations of these chambers were undertaken using the Fluent computational fluid dynamics software. Differences between the observed and simulated flow patterns are discussed. The simulated flow fields were used to estimate chamber efficiency using particle tracking. Efficiency results are presented as efficiency cusps, with efficiency plotted as a function of settling velocity. The cusp represents a range of efficiency values, and approaches to the estimation of an overall efficiency value from these cusps are briefly discussed. Estimates of total efficiency based on the observed settling velocity distribution differed from the measured values by an average of ±17%. However, estimates of steady flow efficiency were consistently higher than the observed values. The simulated efficiencies agreed with the field observations in identifying the most efficient configuration.

Analysis of Droplet Impacting on Inclined Wall

2020 ◽  
Author(s):  
Bowen Chen ◽  
Bo Wang ◽  
Bingzheng Ke ◽  
Ru Li ◽  
Ruifeng Tian
Keyword(s):  
Steam Generator ◽  
High Speed ◽  
Nuclear Power ◽  
Separation Efficiency ◽  
Inertial Force ◽  
High Speed Photography ◽  
Separation Mechanism ◽  
The Relationship ◽  
Plate Separator

Abstract The steam generator is an important part of the nuclear power plant, and the corrugated plate separator plays the important role of drying steam in the steam generator to improve power generation efficiency and protect the safety of the system. The separation mechanism of the corrugated plate separator is relatively complicated. The droplets are moved by the drag force of the steam and gravity in the corrugated plate separator, and captured by the wall of the corrugated plate separator. When the velocity is increased, the inertial force of droplet is increased, so that the droplet is more easily captured by the wall of the corrugated plate separator, and the separation efficiency of the corrugated plate separator is increased. In this paper, the phenomenon of droplet impact on the inclined wall is studied by high-speed photography technology, and the cause and mechanism of the phenomenon are analyzed. By analyzing the spreading and splashing on the droplets impacting on the inclined wall, the relationship between the inclination angle of the droplet impacting on the inclined wall and the spreading is obtained, and the influence of droplets with different Weber numbers, and dry and wetted walls were analyzed, which provide a basis for the optimization of the corrugated plate separator.

scholarly journals Influence of Discharge Gap On Material Removal and Melt Pool Movement in EDM Discharge Process

2021 ◽  
Author(s):  
Xiaoming Yue ◽  
Ji Fan ◽  
Qi Li ◽  
Xiaodong Yang ◽  
Zuoke Xu ◽  
...  
Keyword(s):  
Heat Flux ◽  
Material Removal ◽  
High Speed ◽  
Electrical Discharge Machining ◽  
External Pressure ◽  
High Speed Photography ◽  
Discharge Process ◽  
Melt Pool ◽  
Discharge Gap ◽  
Gap Width

Abstract In electrical discharge machining (EDM), gap control is the key to stable processing; the discharge gap plays a significant role in EDM. To determine the influence of the discharge gap on material removal and melt pool movement, which are two fundamental issues in EDM, high-speed photography and molecular dynamics (MD) simulations were used to study the discharge process. Research results demonstrate that the discharge gap has a significant influence on material removal during the discharge process. A smaller gap width produces more and larger removed materials. The influence mechanism of the gap width on material removal is explained as follows. A smaller gap width produces discharge plasma with a smaller diameter and greater heat flux. Discharge with a greater heat flux generates more material removed during the discharge process. In addition, a smaller gap width and greater heat flux produce a stronger interaction of metal vapor jets, generating a stronger shear force acting on the melt pool. The discharge gap also influences the movement of the melt pool and the final topography of the discharge crater through external pressure acting on the melt pool. Smaller gap width produces greater external pressure acting on the melt pool, generating a bowl-shaped melt pool and a discharge crater with a depression in the center and a bulge around the edge. A larger gap width produces less external pressure acting on the melt pool, generating a flat melt pool and a discharge crater with swelling in the center and a depression around the edge.

scholarly journals Experimental Study on Electric Potential Response Characteristics of Gas-Bearing Coal During Deformation and Fracturing Process

Processes ◽  
2019 ◽  
Vol 7 (2) ◽  
pp. 72 ◽  
Author(s):  
Zhonghui Li ◽  
Yue Niu ◽  
Enyuan Wang ◽  
Lanbo Liu ◽  
Honghao Wang ◽  
...  
Keyword(s):  
Damage Evolution ◽  
High Speed ◽  
Electrical Potential ◽  
Test System ◽  
Stress Change ◽  
High Speed Photography ◽  
Response Characteristics ◽  
Fracturing Process ◽  
Erosion Effect ◽  
Gas Bearing

Coal mass is deformed and fractured under stress to generate electrical potential (EP) signals. The mechanical properties of coal change with the adsorption of gas. To investigate the EP response characteristics of gas-bearing coal during deformation and fracture, a test system to monitor multi-parameters of gas-bearing coal under load was designed. The results showed that abundant EP signals were generated during the loading process and the EP response corresponded well with the stress change and crack expansion, and validated this with the results from acoustic emission (AE) and high-speed photography. The higher stress level and the greater the sudden stress change led to the greater EP abnormal response. With the increase of gas pressure, the confining action and erosion effect are promoted, causing the damage evolution impacted and failure characteristics changes. As a result, the EP response is similar while the characteristics were promoted. The EP response was generated due to the charge separation caused by the friction effect etc. during the damage and deformation of the coal. Furthermore, the main factors of the EP response were different under diverse loading stages. The presence of gas promoted the EP effect. When the failure of the coal occurred, EP value rapidly rose to a maximum, which could be considered as an anomalous characteristic for monitoring the stability and revealing failure of gas-bearing coal. The research results are beneficial for further investigating the damage-evolution process of gas-bearing coal.

Numerical Simulation on the Effect of Inlet-Collision in Oil-Gas Separator Used for Air-Conditioning System

2013 ◽  
Vol 448-453 ◽  
pp. 3378-3381
Author(s):  
Jian Jun Meng ◽  
Yi Luo ◽  
Gang Yan ◽  
Jian Mei Feng
Keyword(s):  
Air Conditioning ◽  
Separation Efficiency ◽  
Three Dimensional ◽  
Separation Performance ◽  
Gas Field ◽  
Pipe Length ◽  
Air Conditioning System ◽  
Inlet Velocity ◽  
Gas Separator ◽  
Oil Gas

A three-dimensional steady-state numerical model of oil-gas separator with inlet-collision structure used in small-sized Variable Refrigerant Flow (VRF) system was established. RNG k-ε model was used in gas field and DRW model was chosen for oil droplets tracking. The influence of inlet-collision on velocity distribution, separation efficiency and pressure loss were studied. The results showed that the inlet-collision structure which had smaller radio of inner pipe length to cyclone bodys height could achieve the same separation efficiency as the no inlet-collision structure with bigger cyclone diameter. Higher separation performance could be obtained when the inlet-collision proportion was less than 26.57% and inlet velocity was about 24 m·s-1.

Flow Boiling on Micropin Fins Entrenched Inside a Microchannel—Flow Patterns and Bubble Departure Diameter and Bubble Frequency

2010 ◽  
Vol 132 (4) ◽  
Author(s):  
Santosh Krishnamurthy ◽  
Yoav Peles
Keyword(s):  
High Speed ◽  
Flow Boiling ◽  
Bubbly Flow ◽  
Nucleate Boiling ◽  
Flow Patterns ◽  
Heat Fluxes ◽  
High Speed Photography ◽  
Bubble Frequency ◽  
Pin Fins ◽  
Parallel Microchannels

Flow boiling of HFE 7000 in five parallel microchannels of 222 μm hydraulic diameter, each containing a single row of 24 in-line 100 μm pin fins, was investigated. High speed photography revealed the dominant flow patterns, namely, the bubbly flow, the multiple flow, and the wavy-annular flow. The interaction of the bubble with the pin fins during nucleate boiling from G=350 kg/m2 s to G=827 kg/m2 s and wall heat fluxes from 10 W/cm2 to 110 W/cm2 is detailed.

Structure of Emulsion Cavitation Jet and Jet Peening Impact on the Fatigue of Plan Carbon Steel Q235A

2011 ◽  
Vol 189-193 ◽  
pp. 476-483
Author(s):  
Zhi Sun ◽  
Yan Wei Sui ◽  
Jun Li ◽  
Yan Ni Zhou
Keyword(s):  
Carbon Steel ◽  
High Speed ◽  
Test System ◽  
Water Jet ◽  
High Speed Photography ◽  
Strengthening Effect ◽  
Initial Stage ◽  
Jet Impact ◽  
Upstream Pressure ◽  
Crack Initiation Life

Due to developing the strengthening effect of liquid jet peening on the surface modification for metallic materials, in this study, an emulsion jet peening is produced by injecting a high-speed emulsion jet into an emulsion filled tank. The test system and fixed emulsion of cavitation jet was developed. High speed photography technique was used to observe and analysis the structure of emulsion cavitation jet at various upstream pressures . The results indicate that the structure of emulsion cavitation jet in terms of jet impact pressure, intensive degree and uniformity is better than that water jet. The jet structure depends on the jet pressure. The cavitation jet length increases rapidly at the initial stage and then it stabilizes after few milliseconds. The stabilized length of jet increases and the diverges angle decreases with increasing pressures. Specimens made of plan carbon steel (Q235A, China standard) were exposed to emulsion jet peening at the stand-off distances of 20 mm with a constant upstream pressure, 20 MPa for 60 s. The fatigue test shows that the crack initiation life by treatment of emulsion jet peening increases about 12.5% and 20.2% compared to water jet and unpeened specimen respectively.

scholarly journals The Mechanical and Reaction Behavior of PTFE/Al/Fe2O3 under Impact and Quasi-Static Compression

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Jun-yi Huang ◽  
Xiang Fang ◽  
Yu-chun Li ◽  
Bin Feng ◽  
Huai-xi Wang ◽  
...  
Keyword(s):  
High Speed ◽  
Xrd Analysis ◽  
High Speed Photography ◽  
Experimental Conditions ◽  
Static Compression ◽  
Reaction Behavior ◽  
Drop Weight ◽  
Weight Test ◽  
Drop Weight Test ◽  
Quasi Static Compression

Quasi-static compression and drop-weight test were used to characterize the mechanical and reaction behavior of PTFE/Al/Fe2O3 composites. Two kinds of PTFE/Al/Fe2O3 composites were prepared with different mass of PTFE, and the reaction phenomenon and stress-strain curves were recorded; the residuals after reaction were analyzed by X-ray diffraction (XRD). The results showed that, under quasi-static compression condition, the strength of the materials is increased (from 37.1 Mpa to 77.2 Mpa) with the increase of PTFE, and the reaction phenomenon occurred only in materials with high PTFE content. XRD analysis showed that the reaction between Al and Fe2O3 was not triggered with identical experimental conditions. In drop-weight tests, PTFE/Al/Fe2O3 specimens with low PTFE content were found to be more insensitive by high-speed photography, and a High Temperature Metal Slag Spray (HTMSS) phenomenon was observed in both kinds of PTFE/Al/Fe2O3 composites, indicating the existence of thermite reaction, which was confirmed by XRD. In PTFE/Al/Fe2O3 system, the reaction between PTFE and Al precedes the reaction between Al and Fe2O3.

Flow Patterns of Oil/Water Two-Phase Upflows in a Small Vertical Tube

2011 ◽  
Vol 396-398 ◽  
pp. 274-278
Author(s):  
Zhen Ying Zhao ◽  
Jia Hao Wang ◽  
Hai Yan Min ◽  
Li Min Yang ◽  
Ji He Yang
Keyword(s):  
High Speed ◽  
Theoretical Models ◽  
Flow Patterns ◽  
Vertical Tube ◽  
Stainless Steel Tube ◽  
Internal Diameter ◽  
Two Phase ◽  
Experimental Conditions ◽  
Transparent Plastic ◽  
Oil Water

The flow patterns of oil/water two-phase upward flows in a small vertical tube with an internal diameter of 0.010 m were investigated by high speed video system. Using stainless steel tube as test section, transparent plastic tube as observing section and deionized water and kerosene (density of 796kg/m3) as working fluids, 5 flow patterns, i.e., annular, churn, slug, bubble and dispersed droplets, were observed under the experimental conditions. The transition boundaries of these flow patterns were compared with the literature and theoretical models of Taitel et al [1] for gas-liquid upward flows. There are some differences of the transition boundaries between the present study and the literature of either gas-liquid or liquid-liquid systems. The theoretical models of Taitel et al can well predict the transition boundaries from annular to churn and from churn to bubble.

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