scholarly journals Radioisotope measurements of the liquid-gas flow in the horizontal pipeline using phase method

2018 ◽  
Vol 180 ◽  
pp. 02032
Author(s):  
Robert Hanus ◽  
Marcin Zych ◽  
Marek Jaszczur ◽  
Leszek Petryka ◽  
Dariusz Świsulski
Keyword(s):  
Gas Phase ◽  
Gas Flow ◽  
Spectral Density Function ◽  
Phase Method ◽  
Two Phase ◽  
Cross Spectral Density ◽  
Flow Investigation ◽  
Phase Liquid ◽  
Gamma Absorption ◽  
Classical Cross

The paper presents application of the gamma-absorption method to a two-phase liquid-gas flow investigation in a horizontal pipeline. The water-air mixture was examined by a set of two Am-241 radioactive sources and two NaI(Tl) scintillation probes. For analysis of the electrical signals obtained from detectors the cross-spectral density function (CSDF) was applied. Results of the gas phase average velocity measurements for CSDF were compared with results obtained by application of the classical cross-correlation function (CCF). It was found that the combined uncertainties of the gas-phase velocity in the presented experiments did not exceed 1.6% for CSDF method and 5.5% for CCF.

scholarly journals Determination of void fraction in two phase liquid-gas flow using gamma absorption

2016 ◽  
Vol 745 ◽  
pp. 032124 ◽  
Author(s):  
M Zych ◽  
R Hanus ◽  
M Jaszczur ◽  
A Strzępowicz ◽  
L Petryka ◽  
...  
Keyword(s):  
Void Fraction ◽  
Gas Flow ◽  
Two Phase ◽  
Phase Liquid ◽  
Gamma Absorption

Modelling post-discharge nitriding and nitrocarburising

2004 ◽  
Vol 120 ◽  
pp. 239-247
Author(s):  
T. Belmonte ◽  
C. Jaoul ◽  
H. Michel
Keyword(s):  
Steady State ◽  
Ternary System ◽  
Gas Phase ◽  
Gas Flow ◽  
State Of The Art ◽  
Active Species ◽  
Surface Phenomena ◽  
Post Discharge ◽  
Two Phase ◽  
Adsorption Surface

In this paper, the state of the art in the modelling of nitriding and nitrocarburising using late post-discharge processes is described. In a first part, interstitial diffusion in ternary system is treated. The problem of the diffusion in two-phase domains is evoked. The chemical pathways in N2-H2 and N2-CH4 post-discharges creating active species are next presented to try to identify the precursors responsible for the transport of nitrogen and carbon to the surface of the solid. Finally, attention is paid to the coupling between the gas phase and the solid. Two different approaches are proposed, either by considering a steady state or a transient gas flow. The latter requires to introduce a sequence of surface phenomena (adsorption, surface diffusion, recombination, dissolution…) that provides a rigorous way to couple processes in the gas phase and in the solid.

Quantitative Visualization of Two-Phase Flow in the Head of Plate-Fin Heat Exchanger

2014 ◽  
Author(s):  
Xincheng Tu ◽  
Sung-jun Kim ◽  
Hyoung-Bum Kim
Keyword(s):  
Heat Exchanger ◽  
Natural Gas ◽  
Gas Phase ◽  
Gas Flow ◽  
Imaging Techniques ◽  
Flow Distribution ◽  
Ccd Cameras ◽  
Two Phase ◽  
Piv Method ◽  
Quantitative Visualization

In this study, we experimentally investigated the distribution of liquid and gas flow in the head of plate-fin heat exchanger. The scale-downed model of proto-type heat exchanger was used and the air and water replaced the natural gas and liquefied natural gas. Two CCD cameras were synchronized with laser to capture the image of liquid-gas flow in the head. Advanced imaging techniques such as LIF, PIV method were used to measure the velocity field of liquid and gas flow simultaneously. The characteristics of momentum transfer process between liquid phase and gas phase are presented in the terms of ensemble averaged result. The effect of liquid mass fraction on the flow distribution was investigated. Then, we quantified the flow distribution of liquid and gas phase for different inlet nozzle configurations.

scholarly journals Axial dispersion of the liquid phase on a three-phase Karr reciprocating plate column

2004 ◽  
Vol 69 (7) ◽  
pp. 581-599 ◽  
Author(s):  
Ljubisa Nikolic ◽  
Vesna Nikolic ◽  
Vlada Veljkovic ◽  
Miodrag Lazic ◽  
Dejan Skala
Keyword(s):  
Liquid Phase ◽  
Gas Flow ◽  
Dispersion Coefficient ◽  
Solid Phase ◽  
Axial Dispersion ◽  
Two Phase ◽  
Three Phase ◽  
Phase Liquid ◽  
Similar Equation ◽  
Plate Column

The influence of the gas flow rate and vibration intensity in the presence of the solid phase (polypropylene spheres) on axial mixing of the liquid phase in a three phase (gas-liquid-solid) Karr reciprocating plate column (RPC) was investigated. Assuming that the dispersionmodel of liquid flow could be used for the real situation inside the column, the dispersion coefficient of the liquid phase was determined as a function of different operating parameters. For a two-phase liquid-solid RPC the following correlation was derived: DL = 1.26(Af)1.42 UL 0.51 ?S 0.23 and a similar equation could be applied with ? 30 % confidence for the calculation of axial dispersion in the case of a three-phase RPC: DL = 1.39(Af)0.47 UL0.42UG0.03 ?S -0.26.

scholarly journals Numerical Simulation of Gas-Particle Two-Phase Flow in a Nozzle with DG Method

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Duan Maochang ◽  
Yu Xijun ◽  
Chen Dawei ◽  
Qing Fang ◽  
Zou Shijun
Keyword(s):  
Flow Field ◽  
Gas Phase ◽  
Mass Fraction ◽  
Gas Flow ◽  
Two Phase Flow ◽  
Phase Flow ◽  
Governing Equations ◽  
Two Phase ◽  
Dg Method ◽  
The Impact

In this paper, the discontinuous Galerkin (DG) method is applied to solve the governing equations of the dispersed two-phase flow with the two-fluid Euler/Euler approach. The resulting governing equations are simple in form and the solution process is very natural. The characteristics of the gas-particle two-phase flow in an engine nozzle are mainly analyzed, and the impacts of the particle mass fraction and particle size on the flow field and engine performance are evaluated. Because of the addition of particles, the gas flow field undergoes significant modifications. Increase in the mass fraction leads to a significant thrust loss in the gas phase, and the impact of the particles on the gas phase could be substantial. Therefore, a quantitative study of thrust loss in the nozzle due to the particle impact is made. It is found that the gas thrust in the two-phase flow is reduced, but the total thrust of the two-phase flow increases to a certain extent.

Synthesis and Microstructural Analysis of Benzylthiol-functionalized Au Nanocrystals

2006 ◽  
Vol 959 ◽  
Author(s):  
Floriana Vitale ◽  
Luciana Mirenghi ◽  
Emanuela Piscopiello ◽  
Maria Lucia Protopapa ◽  
Leander Tapfer ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Au Nanoparticles ◽  
Microstructural Analysis ◽  
High Resolution Electron Microscopy ◽  
Phase Method ◽  
Two Phase ◽  
X Ray ◽  
Resolution Electron ◽  
Phase Liquid ◽  
Ir Emission

ABSTRACTWe report on the synthesis and microstructural and microanalytical analysis of dodecanethiol and benzylthiol-stabilized Au nanoparticles (diameter range between 2 nm and 10 nm). Stable functionalized gold nanoparticles were synthesized by using two different routes: a two-phase liquid-liquid method and a one-phase method. The size, strain, shape and crystalline structure of the nanocrystals were determined by a full-pattern X-ray powder diffraction analysis and high-resolution electron microscopy. The chemical environment of the Au nanocrystals and their interaction with the thiols was investigated by X-ray photoelectron spectroscopy. Photoluminescence spectroscopy measurements show a characteristic IR emission at λ=960 nm of small sized Au nanocrystals (∼3 nm). The origin of this IR emission line seems to be correlated to the Au-S bonding and the size of the nanoparticles.

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