Mass transfer into the liquid in turbulent flow at high Schmidt numbers. Dissolution of benzoic acid into aqueous solutions of glycerol from internal surface of the pipe

1981 ◽  
Vol 46 (7) ◽  
pp. 1566-1576
Author(s):  
František Vašák ◽  
Václav Kolář ◽  
Zdeněk Brož
Keyword(s):  
Mass Transfer ◽  
Benzoic Acid ◽  
Aqueous Solutions ◽  
Cross Section ◽  
Circular Cross Section ◽  
Internal Surface ◽  
Theoretical Relation ◽  
Acid Dissolution ◽  
Schmidt Numbers ◽  
Unified Description

Theoretical relation derived in the last study for calculation of the mass transfer coefficient in the region of not fully developed concentration profile at high Schmidt numbers has been verified experimentally. This experimental study has been devoted to measurements of the rate of benzoic acid dissolution into aqueous solutions of glycerol from the internal surface of the pipe of circular cross section in the range 933 ⪬ Sc ⪬ 225 000 and 5 000 ⪬ Re ⪬ 50 000. It has been possible to explain on basis of the theoretical model, the differences between the data of various authors and to obtain a unified description of the phenomena.

scholarly journals Computational Study of Zigzag Spacer Design with Elliptical Cross-Section Filaments

2020 ◽  
Vol 307 ◽  
pp. 01047
Author(s):  
Gohar Shoukat ◽  
Farhan Ellahi ◽  
Muhammad Sajid ◽  
Emad Uddin
Keyword(s):  
Mass Transfer ◽  
Cross Section ◽  
Cross Sections ◽  
Computational Study ◽  
Flow Direction ◽  
Three Dimensional ◽  
Circular Cross Section ◽  
Two Dimensional ◽  
Permeate Flux ◽  
Elliptical Cross

The large energy consumption of membrane desalination process has encouraged researchers to explore different spacer designs using Computational Fluid Dynamics (CFD) for maximizing permeate per unit of energy consumed. In previous studies of zigzag spacer designs, the filaments are modeled as circular cross sections in a two-dimensional geometry under the assumption that the flow is oriented normal to the filaments. In this work, we consider the 45° orientation of the flow towards the three-dimensional zigzag spacer unit, which projects the circular cross section of the filament as elliptical in a simplified two-dimensional domain. OpenFOAM was used to simulate the mass transfer enhancement in a reverse-osmosis desalination unit employing spiral wound membranes lined with zigzag spacer filaments. Properties that impact the concentration polarization and hence permeate flux were analyzed in the domain with elliptical filaments as well as a domain with circular filaments to draw suitable comparisons. The range of variation in characteristic parameters across the domain between the two different configurations is determined. It was concluded that ignoring the elliptical projection of circular filaments to the flow direction, can introduce significant margin of error in the estimation of mass transfer coefficient.

Mass transfer into the liquid in turbulent flow at high Schmidt numbers. Theoretical solution

1981 ◽  
Vol 46 (6) ◽  
pp. 1445-1457
Author(s):  
František Vašák ◽  
Václav Kolář ◽  
Zdeněk Brož
Keyword(s):  
Mass Transfer ◽  
Velocity Profile ◽  
Turbulent Flow ◽  
Theoretical Solution ◽  
Theoretical Relation ◽  
Transfer Coefficients ◽  
Mass Transfer Coefficients ◽  
Entrance Section ◽  
Schmidt Numbers ◽  
Steady Velocity

Theoretical relation is derived describing the mass transfer into the liquid in turbulent flow with steady velocity profile, at high Schmidt numbers Sc ≥ 103 in the concentration entrance section. Graphical dependences describing the effect of parameters of the model on mass transfer coefficients are presented and discussed. It is demonstrated that for the limiting cases the derived theoretical solution transforms into familiar relations (asymptotes).

scholarly journals Absorption of Co2 into Perfluorinated Gas Carrier in the Taylor Gas–Liquid Flow in a Microchannel System

2012 ◽  
Vol 33 (4) ◽  
pp. 595-602 ◽  
Author(s):  
Paweł Sobieszuk ◽  
Maciej Pilarek
Keyword(s):  
Mass Transfer ◽  
Cross Section ◽  
Slug Flow ◽  
Circular Cross Section ◽  
Bioprocess Engineering ◽  
Theoretical Approaches ◽  
Physicochemical System ◽  
Liquid Mass Transfer ◽  
Gas Liquid Flow ◽  
Respiratory Gases

The aim of this study was to determine the solubility of CO2 in perfluorodecalin (PFD) which is frequently used as efficient liquid carrier of respiratory gases in bioprocess engineering. The application of perfluorinated liquid in a microsystem has been presented. Gas-liquid mass transfer during Taylor (slug) flow in a microchannel of circular cross section 0.4 mm in diameter has been investigated. A physicochemical system of the absorption of CO2 from the CO2/N2 mixture in perfluorodecalin has been applied. The Henry’s law constants have been found according to two theoretical approaches: physical (H = 1.22·10-3 mol/m3Pa) or chemical (H = 1.26·10-3 mol/m3Pa) absorption. We are hypothesising that the gas-liquid microchannel system is applicable to determine the solubility of respiratory gases in perfluorinated liquids.

SAF file: It's really three dimensional file

2018 ◽  
Vol 14 (1) ◽  
pp. 1
Author(s):  
Prof. Dr. Jamal Aziz Mehdi
Keyword(s):  
Cross Section ◽  
Root Canal ◽  
Three Dimensional ◽  
Circular Cross Section ◽  
Circular Motion ◽  
Root Canal Treatment ◽  
Metal Core ◽  
Rotating Blade

The biological objectives of root canal treatment have not changed over the recentdecades, but the methods to attain these goals have been greatly modified. Theintroduction of NiTi rotary files represents a major leap in the development ofendodontic instruments, with a wide variety of sophisticated instruments presentlyavailable (1, 2).Whatever their modification or improvement, all of these instruments have onething in common: they consist of a metal core with some type of rotating blade thatmachines the canal with a circular motion using flutes to carry the dentin chips anddebris coronally. Consequently, all rotary NiTi files will machine the root canal to acylindrical bore with a circular cross-section if the clinician applies them in a strictboring manner

Experimental study on mass transfer comparison of two liquid desiccants aqueous solutions

2014 ◽  
pp. 665-670
Author(s):  
S. Bouzenada ◽  
T. Salmon ◽  
L. Fraikin ◽  
A. Kaabi ◽  
A. Léonard
Keyword(s):  
Mass Transfer ◽  
Experimental Study ◽  
Aqueous Solutions
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