Transitional Flow in a Rushton Turbine Stirred Tank

Yulong Zhang, Zhengming Gao, Zhipeng Li, J.J. Derksen

Research output: Contribution to journalArticle

12 Citations (Scopus)
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Abstract

The way in which the single phase flow of Newtonian liquids in the vicinity of the impeller in a Rushton turbine stirred tank goes through a laminar – turbulent transition has been studied in detail experimentally (with Particle Image Velocimetry, PIV) as well as computationally. For Reynolds numbers equal to or higher than 6,000, the average velocities and velocity fluctuation levels scale well with the impeller tip speed, i.e. show Reynolds independent behavior. Surprising flow structures were measured – and confirmed through independent experimental repetitions – at Reynolds numbers around 1,300. Upon reducing the Reynolds number from values in the fully turbulent regime, the trailing vortex system behind the impeller blades weakens with the upper vortex weakening much stronger than the lower vortex. Simulations with a variety of methods (direct numerical simulations, transitional turbulence modeling) and software implementations (ANSYS-Fluent commercial software, lattice-Boltzmann in-house software) have only partial success in representing the experimentally observed laminar – turbulent transition.
Original languageEnglish
Pages (from-to)3610–3623
Number of pages14
JournalAIChE Journal
Volume63
Issue number8
Early online date7 Jun 2017
DOIs
Publication statusPublished - 1 Aug 2017

Fingerprint

laminar-turbulent transition
Reynolds number
turbine
vortex
Vortex flow
Turbines
Software
software
Newtonian liquids
single-phase flow
Rheology
Direct numerical simulation
flow structure
Flow structure
Velocity measurement
simulation
Turbulence
turbulence
liquid
modeling

Keywords

  • transitional flow
  • stereoscopic particle image velocimetry
  • Rushton turbine
  • computational fluid dynamics
  • stirred tank

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Chemical Engineering(all)
  • Environmental Science(all)

Cite this

Transitional Flow in a Rushton Turbine Stirred Tank. / Zhang, Yulong; Gao, Zhengming; Li, Zhipeng; Derksen, J.J.

In: AIChE Journal, Vol. 63, No. 8, 01.08.2017, p. 3610–3623.

Research output: Contribution to journalArticle

Zhang, Yulong ; Gao, Zhengming ; Li, Zhipeng ; Derksen, J.J. / Transitional Flow in a Rushton Turbine Stirred Tank. In: AIChE Journal. 2017 ; Vol. 63, No. 8. pp. 3610–3623.
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