A novel approach to the correlation of mass transfer rates in bubble columns with non- Newtonian liquids

The paper presents a mechanistic/deterministic model for simulation of mass removal during air sparging. From the point of numerical modeling, there are two issues considering air sparging: modeling of air flow and distribution and modeling of mass transport and transfer. Several processes, which are commonly neglected, such as air channeling and pollutant advection by the water phase, are taken into account. The numerical model presented in this paper considers all relevant for mass transfer during the air sparging. Model includes hydrodynamics of air and water phase; calculated air volume content is divided into a number of air channels surrounded by the water phase, which is divided into two compartments. First compartment is immobile and it is in contact with air phase, while the second compartment is mobile. This “mobile-immobile” formulation is a common approach for description of solute transport by groundwater. Mass transfer between two water compartments is modeled as a first order kinetic, where the mass transfer coefficient, representing diffusion and advection in the water phase towards the air channels, is parameter needed to be calibrated. Sorption for both water compartments is considered. The adopted model of contaminant evaporation at the air-water interface is verified by comparison with experimental results available from published sources. Model is used for simulation of two-dimensional air sparging laboratory experiment. Good overall agreement is observed. It is showed that the efficiency of air sparging can be influenced by natural groundwater flow.

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Absorption of oxygen into solutions of polymers

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19862127 ◽

1986 ◽

Vol 51 (10) ◽

pp. 2127-2134 ◽

Cited By ~ 1

Author(s):

František Potůček ◽

Jiří Stejskal

Keyword(s):

Mass Transfer ◽

Aqueous Solutions ◽

Transfer Coefficient ◽

Mass Transfer Coefficient ◽

Flow Rate ◽

Liquid Flow ◽

Flow Curve ◽

Liquid Flow Rate ◽

Polymer Concentration ◽

Newtonian Liquids

Absorption of oxygen into water and aqueous solutions of poly(acrylamides) was studied in an absorber with a wetted sphere. The effects of changes in the liquid flow rate and the polymer concentration on the liquid side mass transfer coefficient were examined. The results are expressed by correlations between dimensionless criteria modified for non-Newtonian liquids whose flow curve can be described by the Ostwald-de Waele model.

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Effects of Variable Transport Properties on Heat and Mass Transfer in MHD Bioconvective Nanofluid Rheology with Gyrotactic Microorganisms: Numerical Approach

Coatings ◽

10.3390/coatings11020231 ◽

2021 ◽

Vol 11 (2) ◽

pp. 231

Author(s):

Muhammad Awais ◽

Saeed Ehsan Awan ◽

Muhammad Asif Zahoor Raja ◽

Nabeela Parveen ◽

Wasim Ullah Khan ◽

...

Keyword(s):

Mass Transfer ◽

Transport Properties ◽

Heat And Mass Transfer ◽

Group Analysis ◽

Numerical Approach ◽

Validity Of Results ◽

Gyrotactic Microorganisms ◽

Transfer Rates ◽

Buongiorno’S Model ◽

Density Distributions

Rheology of MHD bioconvective nanofluid containing motile microorganisms is inspected numerically in order to analyze heat and mass transfer characteristics. Bioconvection is implemented by combined effects of magnetic field and buoyancy force. Gyrotactic microorganisms enhance the heat and transfer as well as perk up the nanomaterials’ stability. Variable transport properties along with assisting and opposing flow situations are taken into account. The significant influences of thermophoresis and Brownian motion have also been taken by employing Buongiorno’s model of nanofluid. Lie group analysis approach is utilized in order to compute the absolute invariants for the system of differential equations, which are solved numerically using Adams-Bashforth technique. Validity of results is confirmed by performing error analysis. Graphical and numerical illustrations are prepared in order to get the physical insight of the considered analysis. It is observed that for controlling parameters corresponding to variable transport properties c2, c4, c6, and c8, the velocity, temperature, concentration, and bioconvection density distributions accelerates, respectively. While heat and mass transfer rates increases for convection parameter and bioconvection Rayleigh number, respectively.

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Prediction of Growth Parameters of Frost Deposits in Forced Convection

Journal of Heat Transfer ◽

10.1115/1.3244426 ◽

1981 ◽

Vol 103 (1) ◽

pp. 3-6 ◽

Cited By ~ 17

Author(s):

J. E. White ◽

C. J. Cremers

Keyword(s):

Mass Transfer ◽

Forced Convection ◽

Growth Parameters ◽

Experimental Investigations ◽

Experimental Conditions ◽

Transfer Rates ◽

Air Stream ◽

Transient Period ◽

Approximate Expressions ◽

Frost Layer

Experimental investigations of frost deposition under forced convection conditions have shown that in most cases heat and mass transfer rates become constant after an initial transient period. It is shown that, in such cases, approximately half of the mass transfer from a humid air stream to a frost layer diffuses inward, condenses and increases the density of the frost. The other half is deposited at the surface and increases the thickness of the layer. Approximate expressions for density and thickness of the frost layer are derived and compared with data from the literature and also with experimental work reported in this paper. The correlations are shown to work well for a broad range of experimental conditions.

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