A study on blending characteristics of axial flow impellers

• Authors: Ivan Fořt , Tomáš Jirout
• Languages of publication: EN

Abstracts

EN

This paper presents an analysis of the blending characteristics of axial flow high-speed impellers under a turbulent regime of flow of an agitated low viscosity liquid. The conductivity method is used to determine the time course of blending (homogenisation) of miscible liquids in a pilot plant fully baffled mixing vessel, and a torquemeter is used for measuring the impeller power input in the same system. Four-blade and six-blade pitched blade impellers and three high efficiency axial flow impellers are tested for the given degree of homogeneity (98%).The experimental results and also the results of the authors' previous study, in accordance with the theoretical approach described in the literature, show that there is a universal relationship between the impeller power number and the dimensionless blending time, taking into consideration the impeller-to-vessel diameter ratio, independent of the geometry of the axial flow impeller but dependent on the degree of homogeneity. This relationship is found to be valid on a pilot plant scale under a turbulent flow regime of an agitated liquid.

Keywords

EN

axial flow impeller; pitched-blade impeller; turbulent flow; impeller power input; blending time

• Publisher: De Gruyter Open
• Journal: Chemical and Process Engineering
• Year: 2011
• Volume: 32
• Issue: 4
• Pages: 311-319

Dates

published

1 - 12 - 2011

online

15 - 2 - 2012

Contributors

author

Ivan Fořt

• Faculty of Mechanical Engineering, Department of Process Engineering, Czech Technical University in Prague, Technická 4, 166 07 Prague 6, Czech Republic

author

Tomáš Jirout

• Faculty of Mechanical Engineering, Department of Process Engineering, Czech Technical University in Prague, Technická 4, 166 07 Prague 6, Czech Republic

References

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Identifiers

DOI

10.2478/v10176-011-0025-3