Local Turbulent Energy Dissipation Rate in a Vessel Agitated by a Rushton Turbine

• Authors: Radek Šulc , Vít Pešava , Pavel Ditl
• Languages of publication: EN

Abstracts

EN

The scaling of turbulence characteristics such as turbulent fluctuation velocity, turbulent kinetic energy and turbulent energy dissipation rate was investigated in a mechanically agitated vessel 300 mm in inner diameter stirred by a Rushton turbine at high Reynolds numbers in the range 50 000 < Re < 100 000. The hydrodynamics and flow field was measured using 2-D TR PIV. The convective velocity formulas proposed by Antonia et al. (1980) and Van Doorn (1981) were tested. The turbulent energy dissipation rate estimated independently in both radial and axial directions using the one-dimensional approach was not found to be the same in each direction. Using the proposed correction, the values in both directions were found to be close to each other. The relation ε/(N3·D2) ∞ const. was not conclusively confirmed.

Keywords

EN

mixing; Rushton turbine; local turbulent energy dissipation rate; energy spectrum function; fluctuation velocity

• Publisher: De Gruyter Open
• Journal: Chemical and Process Engineering
• Year: 2015
• Volume: 36
• Issue: 2
• Pages: 135-149

Dates

published

1 - 6 - 2015

online

17 - 7 - 2015

revised

18 - 2 - 2015

received

22 - 11 - 2014

accepted

24 - 4 - 2015

Contributors

author

Radek Šulc

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

author

Vít Pešava

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

author

Pavel Ditl

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

References

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Identifiers

DOI

10.1515/cpe-2015-0011