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

• Autorzy: Šulc R. , Pešava V. , Ditl P.

Identyfikatory

DOI

10.1515/cpe-2015-0011

• Języki publikacji: EN

Abstrakty

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 /(N3·D2)  const. was not conclusively confirmed.

Słowa kluczowe

EN

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

PL

mieszanie; turbina Rushtona; rozpraszanie energii; widmo energii; prędkość wahania

• Wydawca: Komitet Inżynierii Chemicznej i Procesowej Polskiej Akademii Nauk
• Czasopismo: Chemical and Process Engineering
• Rocznik: 2015
• Tom: Vol. 36, nr 2
• Strony: 135--149
• Opis fizyczny: Bibliogr. 15 poz., rys. tab.

Twórcy

autor

Šulc R.

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

autor

Pešava V.

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

autor

Ditl P.

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

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