Evaluation of a concentrated parameters mathematical model applied to drying of yerba mate leaves with variable mass transfer coefficient

A mathematical model considering the inter-phase mass transfer both in the down-comer and the riser of an external-loop airlift reactor was established in this paper. The calculated global volumetric mass transfer coefficient based on the assumption of continuous stirred tank reactor (CSTR) was different from the local volumetric mass transfer coefficients by the newly proposed mathematical model and the difference was discussed. The effects of mass transfer in the down-comer, the hydrodynamic pressure and the experimental time on the mass transfer coefficient measurement model have been studied in detail. And it was also proved that only the global volumetric mass transfer coefficient, but not the local volumetric mass coefficient, can be obtained from a time-concentration curve in the external-loop airlift reactor.

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Predictions of capillary oxygen transport in the presence of fluorocarbon additives

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1998.275.6.h2250 ◽

1998 ◽

Vol 275 (6) ◽

pp. H2250-H2257 ◽

Cited By ~ 8

Author(s):

Charles D. Eggleton ◽

Tuhin K. Roy ◽

Aleksander S. Popel

Keyword(s):

Mathematical Model ◽

Mass Transfer ◽

Transfer Coefficient ◽

Mass Transfer Coefficient ◽

Oxygen Transport ◽

Retractor Muscle ◽

Additional Increase ◽

Fluorocarbon Emulsion

A mathematical model of capillary oxygen transport was formulated to determine the effect of increasing plasma solubility, e.g., by the addition of an intravascular fluorocarbon emulsion. The effect of increased plasma solubility is studied for two distributions of fluorocarbon, when the fluorocarbon droplets are uniformly distributed throughout the plasma and when the fluorocarbon droplets are concentrated in a layer adjacent to the endothelium. The model was applied to working hamster retractor muscle at normal and lowered hematocrit. The intracapillary mass transfer coefficient was found to increase by 18% as the solubility was increased by a factor of 1.7 at a hematocrit of 43%. An additional increase of 6% was predicted when the solubility increase was concentrated in the layer adjacent to the endothelium. At a hematocrit of 25%, the intracapillary mass transfer coefficient increased 14% when the solubility was increased by a factor of 1.7.

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Mathematical Model for Calculating Oxygen Mass Transfer Coefficient in Diffused Air Systems

AL-Rafdain Engineering Journal (AREJ) ◽

10.33899/rengj.2011.26795 ◽

2011 ◽

Vol 19 (4) ◽

pp. 43-54 ◽

Cited By ~ 4

Author(s):

Kossay K. Al-Ahmady

Keyword(s):

Mathematical Model ◽

Mass Transfer ◽

Transfer Coefficient ◽

Mass Transfer Coefficient ◽

Oxygen Mass Transfer

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Kinetic Regularities and Mathematical Modelling of Potassium Chloride Dissolution

Chemistry & Chemical Technology ◽

10.23939/chcht15.01.148 ◽

2021 ◽

Vol 15 (1) ◽

pp. 148-152

Author(s):

Dmytro Symak ◽

◽

Vira Sabadash ◽

Jaroslaw Gumnitsky ◽

Zoriana Hnativ ◽

...

Keyword(s):

Mathematical Model ◽

Mass Transfer ◽

Transfer Coefficient ◽

Mass Transfer Coefficient ◽

Potassium Chloride ◽

Potassium Salt ◽

Solid Particles ◽

Mechanical Stirring ◽

Salt Dissolution ◽

Countercurrent Process

The dissolution process of potassium chloride particles in the apparatus with two-blade mechanical stirrer was investigated and the mass transfer coefficient was determined. The experimental results were generalized by criterion dependence. The independence of the mass transfer coefficient from the solid particles diameter was confirmed. A countercurrent process of potassium salt dissolution in two apparatuses with a mechanical stirring was considered. A mathematical model for countercurrent dissolution was developed and the efficiency of this process was determined.

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