Results 251 to 260 of about 1,854,799 (291)

Correlation of axial mixing of solids in fluidized beds by a dispersion coefficient

Powder Technology, 1984
Abstract Axial mixing of solids in a 19.3 cm diameter bed was investigated using a tracer technique. Bed material and tracer consisted of ion-exchange resin particles of 0.846 mm and 0.645 mm diameter, respectively. Tracer concentration profiles were measured. The results were expressed as axial dispersion coefficients.
A. Esin, M. Altun
openaire   +1 more source

A simplified model for prediction of time-dependent axial dispersion coefficient

Chemical Engineering Science, 1991
Abstract A simple model is proposed for prediction of the axial dispersion coefficient as a function of time. The model contains only a single parameter called the decay time, which is the time required for the mean concentration to approach 1 e of its initial value. The asymptotic value of this coefficient for large times approaches the value
Mohammad Soltanieh, Sasan Sadraei
openaire   +1 more source

Axial Dispersion Coefficients in Laminar Flows of Water-Distribution Systems

Journal of Hydraulic Engineering, 2011
Because longitudinal dispersion is becoming increasingly germane to the problem of accurately determining water quality, water-resource managers and engineers seeking to represent solute transport in drinking-water systems must be able to compute relevant dispersion coefficients.
Pedro Romero-Gomez, Christopher Y. Choi
openaire   +1 more source

Measurement of transverse and axial apparent dispersion coefficients in packed beds

AIChE Journal, 1996
AbstractThe axial and transverse apparent dispersion coefficients of three solvents in two packed chromatographic columns were determined by pulsed‐field‐gradient nuclear‐magnetic resonance in a range of mobile phase velocity. The column beds were packed with 5‐ μm particles of porous C18 silica or 30‐μm particles of silica.
Ulrich Tallarek, Klaus Albert, Ernst Bayer, Georges Guiochon   +3 more
openaire   +1 more source

Axial dispersion coefficients in packed beds at low reynolds numbers

The Canadian Journal of Chemical Engineering, 1969
AbstractPeclet numbers describing axial dispersion in gas flow through packed beds of spheres were obtained using a two measurement point, pulse technique in a test section four inches inside diameter and 5.14 feet high. Three packing sizes were investigated, corresponding to tube to particle diameter ratios of 6.4, 17, and 66In the experiments the ...
Jack C. Urban, A. Gomezplata
openaire   +1 more source

The simultaneous determination of axial dispersion and mass transfer coefficients

Chemical Engineering Science, 1967
Abstract A method is illustrated for the simultaneous determination of axial dispersion and mass transfer parameters for some continuous flow process operations. The procedure involves the matching of computed and experimental axial concentration profiles.
openaire   +1 more source

Experimental characterization of axial dispersion in coiled flow inverters [PDF]

Chemical Engineering Research and Design, 2017
Narrow residence time distributions (RTDs) are desirable in many chemical engineering processes. However, when a system operates in the laminar flow regime, significant fluid dynamic dispersion takes place.
Luca Mazzei, Asterios Gavriilidis
exaly   +3 more sources

CFD Simulation of Flow and Axial Dispersion in External Loop Airlift Reactor

Chemical Engineering Research and Design, 2006
In the present work, a CFD simulation, using two-fluid model, has been performed to obtain the flow pattern and the gas hold-up in external loop air-lift reactors (EL-ALR).
J B Joshi
exaly   +2 more sources

A unified correlation for predicting liquid axial dispersion coefficient in bubble columns

Chemical Engineering Science, 2001
Abstract Experimental measurements of gas holdup and liquid axial dispersion coefficients have been carried out in two bubble columns (column I; D c =15 cm and column II; D c =20 cm ), operating with co-current upflow of gas and liquid. In addition, measurement of bubble size was investigated.
S Moustiri, G Hebrard, S.S Thakre, M Roustan   +3 more
openaire   +1 more source

Modelling of concentration profiles in tower fermenter. The influence of the axial dispersion coefficient

Biotechnology Letters, 1991
The production of CO2 in tower fermenters which can cause back mixing, and thereby reducing the efficiency of such fermenters has been modelled with respect to fermentation. It is confirmed that the effect is significant. The effect of variations in the kinetic parameters, the maximum specific growth rate and the biomass yield coefficient was found to ...
T Setiadi, V. F. Larsen
openaire   +1 more source