Large-eddy simulation of turbulent flow in an unbaffled stirred tank driven by a Rushton turbine

Alcamo, Raul; Micale, G.; Grisafi, F.; Brucato, Alberto; Ciofalo, Michele

doi:10.1016/j.ces.2004.11.017

Cited by 128 publications

(99 citation statements)

References 19 publications

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“…Compared with data given by Alcamo et al (2005) for a single Rushton turbine in an unbaffled vessel, qualitative agreement is achieved, although higher values of radial velocity of up to 0.4 · u tip are obtained in this study. This might be an effect of the indirect baffling caused by the probes used in this study since the radial velocities obtained for the completely unbaffled BIOSTAT ® CultiBag 50L are more similar to data given in the literature [Alcamo et al (2005)]. In contrast, Delafosse et al (2008) and Kresta & Wood (1991) give maximum radial velocities in the stirrer discharge of up to 0.8 · u tip .…”

Section: Resultssupporting

confidence: 79%

“…In the vicinity of the upper impeller, fluid velocities reach about 0.4 · u tip , but are significantly lower near the liquid surface. As described by Alcamo et al (2005), the jet of the RT has a slight downward inclination, which can be explained by the absence of baffles. In contrast, slight upwardly inclined radial jets have been found in experimental [Yianneskis et al (1987)] and numerical [Montante et al (2001)] studies on fully baffled vessels with Rushton turbines.…”

Section: Resultsmentioning

confidence: 81%

See 1 more Smart Citation

CFD for Characterizing Standard and Single-use Stirred Cell Culture Bioreactors

Kaiser¹,

Löffelholz²,

Werner³

et al. 2011

Computational Fluid Dynamics Technologies and Applications

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Section: Resultssupporting

confidence: 79%

Section: Resultsmentioning

confidence: 81%

CFD for Characterizing Standard and Single-use Stirred Cell Culture Bioreactors

Kaiser¹,

Löffelholz²,

Werner³

et al. 2011

Computational Fluid Dynamics Technologies and Applications

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“…The trailing vortex reportedly forms behind the blade for the unbaffled vessel. Its trajectory was similar to that for the baffled vessel (Alcamo et al, 2005). However, the rotation rate in that region might differ according to the baffle conditions.…”

Section: Velocity Profile Of the Liquid Flowmentioning

confidence: 58%

Liquid Flow in Impeller Swept Regions of Baffled and Unbaffled Vessels With a Turbine-Type Agitator

Yoshida

Ebina

Shirosaki

et al. 2015

Braz. J. Chem. Eng.

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-Liquid flow in the impeller swept region of vessels with a turbine-type agitator was examined for the flow path between the neighboring blades of the rotating impeller. Visualization of the flow and its measurement were done using particle tracking velocimetry with a camera rotating along with the impeller. Internal liquid flow of the impeller differed when the velocity magnitudes were compared in conditions with and without baffles. Larger circumferential and radial velocities were observed without the baffles and with the baffles, respectively, which was considered to result in the difference of impeller power transmission. Efficiencies produced, based on the flow-head concept, reflected the impeller power characteristics. The turbine-type impeller as an actuator was demonstrated to improve in the flow characteristics with viscous losses increased by the baffles. In terms of impeller efficiencies based on the power consumption, the effect of baffles for the energy was as a decreased transmission and an increased transport.

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“…Indeed, as shown by works of Alcamo et al [22], the flow in unbaffled stirred tank is more intensive in horizontal direction than in vertical one while, in baffled stirred tank, it is more intensive in vertical direction than in horizontal one. In the Nucleo TM bioreactor, it is twice intensive in horizontal direction than in vertical one however this latter remains significant.…”

Section: Comparison Of the Flow Structure Generated In Nucleo Tm Biormentioning

confidence: 91%

Hydrodynamics in a disposable rectangular parallelepiped stirred bioreactor with elliptic pendulum motion paddle

Collignon

Droissart

Delafosse

et al. 2015

Biochemical Engineering Journal

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Stainless steel bioreactors increasingly give way to their disposable counterparts in pharma research as no cleaning or sterilisation is required. This led company ATMI LifeSciences to develop the "Nucleo TM ". Original in design, this disposable bioreactor comprises a rectangular parallelepiped plastic bag stirred by a paddle revolving in elliptic pendulum motion. Studies covering this bioreactor showed good homogeneity of culture medium as well as good productivity for animal cell cultures. To further explain these good performances, the flow inside the "Nucleo TM " must be resolved. This paper focuses on the mean flow description, computed from stereo-PIV measurements performed in 20 vertical covering the whole volume of a 50 dm³ Nucleo TM bioreactor. As the flow is already turbulent in the chosen agitation conditions, its dimensionless mean velocity field does not vary with the paddle rotational speed. Mean flow pattern exhibits an axial symmetry -same flow is observed in opposite quarters of the tank -and can be described as a three-dimensional helix coiled on itself to form a distorted horizontal torus which covers the whole tank volume. Mean velocity is on average twice higher in the cone swept by the paddle and its two horizontal components are twice the vertical one. However, mean velocity remains significant everywhere and, in particular, no stagnant area is observed in tank corners. Above outcomes thus confirm previous studies observations.

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Large-eddy simulation of turbulent flow in an unbaffled stirred tank driven by a Rushton turbine

Cited by 128 publications

References 19 publications

CFD for Characterizing Standard and Single-use Stirred Cell Culture Bioreactors

CFD for Characterizing Standard and Single-use Stirred Cell Culture Bioreactors

Liquid Flow in Impeller Swept Regions of Baffled and Unbaffled Vessels With a Turbine-Type Agitator

Hydrodynamics in a disposable rectangular parallelepiped stirred bioreactor with elliptic pendulum motion paddle

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