An experimental and numerical analysis of the fluid flow in a mechanically agitated vessel

Jaszczur, Marek; Młynarczykowska, A.; Demurtas, Luana

doi:10.1051/e3sconf/201912808002

Cited by 3 publications

(4 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Because of the high risk of the hopper formation and turbulence, in mixers quite often the baffles are used (usually two to four), which separate stirring areas. Researchers obtain a very good agreement between experimental and predicted mixing time over a wide range of impellers geometries or diameter and in the area of number blades, blade width and blade angle [3,4]. Thus, in addition to the stirred vessel geometry, the number, shape and position of the blades also have a significant impact on the power, efficiency and quality of mixing.…”

Section: Introductionmentioning

confidence: 91%

“…Authors showed that the homogenisation process for mixture in a stirred vessel with rotation impeller without baffles does not require much electrical power. Jaszczur et al [4] analysed the process of the fluid flow in the mechanically agitated vessel without baffles with new impeller type versus the Rushton turbine. The authors, as the basis for the assessment of the intensity degree and efficiency of mixing, used the analysis of velocity vectors distribution and power number.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Impact of baffle geometry on the fluid motion in the stirred vessel

Młynarczykowska

Ferrari²,

Demurtas³

et al. 2022

EPJ Web Conf.

View full text Add to dashboard Cite

The fluids mixing is a crucial operation in a large number of engineering systems. It has major significance in chemical engineering, food, cosmetics and pharmaceutics production, biotechnology, wastewater treatment engineering, and countless other applications. Among many available systems online mixing with static mixers and stirred tanks plays a primary role and has been developed to meet several processing objectives. The effectiveness of the mixing process depends on a number of parameters, i.e. impeller shape, mixing phases properties, process conditions as well as stirred vessel design - in particular, number and baffles’ design. The optimal baffles geometry is still an open issue and is usually design with trial and error methods. In this study, the focus is on the experimental investigations of the baffle geometry on the fluid flow and mixing phenomenon as well as on the required by the mixer power. In order to evaluate velocity field and mixing parameters, particle image velocimetry measurement is used whereas to obtain the power consumption by the stirred vessel precise torque meters were used. Measurements are carried out for different Reynolds numbers, to determine the most efficient process parameters. It has been shown that for the analyzed range of Reynolds numbers, the baffles design significantly influences fluid flow motion, mixing phenomena and the pumping number power number, but not affect the power number.

show abstract

Section: Introductionmentioning

confidence: 91%

Section: Introductionmentioning

confidence: 99%

Impact of baffle geometry on the fluid motion in the stirred vessel

Młynarczykowska

Ferrari²,

Demurtas³

et al. 2022

EPJ Web Conf.

View full text Add to dashboard Cite

show abstract

“…The simulation results showed that flow pattern and dimensionless velocity distribution are related to Reynolds number and regime type without change values in the turbulent regime. The lowest drop of total power number for single and parallel configuration of the impellers was observed in laminar regime [5,6,78,79,164]. A large number of researchers have performed numerical simulations to examine the impact of impeller geometry on the mixing process in order to find optimal configuration, low mixing time or low power consumption [165][166][167].…”

Section: The Effect Of Impellersmentioning

confidence: 99%

“…the internal vessel geometry or configuration (baffles, coils, vessel bottom type, etc. [3][4][5][6]); -the fluid properties (densities, number of phases, a viscosity [7]);…”

Section: Introductionmentioning

confidence: 99%

A General Review of the Current Development of Mechanically Agitated Vessels

Jaszczur

Młynarczykowska

2020

Processes

View full text Add to dashboard Cite

The mixing process in a mechanically agitated vessel is a widespread phenomenon which plays an important role among industrial processes. In that process, one of the crucial parameters, the mixing efficiency, depends on a large number of geometrical factors, as well as process parameters and complex interactions between the phases which are still not well understood. In the last decade, large progress has been made in optimisation, construction and numerical and experimental analysis of mechanically agitated vessels. In this review, the current state in this field has been presented. It shows that advanced computational fluid dynamic techniques for multiphase flow analysis with reactions and modern experimental techniques can be used with success to analyse in detail mixing features in liquid-liquid, gas-liquid, solid-liquid and in more than two-phase flows. The objective is to show the most important research recently carried out.

show abstract

CFD simulation of a Rushton turbine stirred-tank using open-source software with critical evaluation of MRF-based rotation modeling

Reid,

Rossi,

Cottini

et al. 2024

Meccanica

View full text Add to dashboard Cite

A critical evaluation of the impact of the Multiple Reference Frame (MRF) technique on steady RANS simulations of a Rushton turbine stirred-tank is presented. The analysis, based on the open-source software OpenFOAM, is focused on the choice of the diameter and thickness of the MRF region and on their effect on the predicted velocity field and mixing times in the tank. Five diameters of the MRF region are compared for the same operating conditions of the turbine, showing limited differences in velocity profiles, which are found in general good agreement with available experimental data. Significant differences are nonetheless found in the predicted levels of turbulence intensity within the tank, with a considerable amount of artificially generated turbulence at the boundary of the MRF region for the largest diameters. The impact of the different predictions of the turbulent field on the modeling of the mixing process in the tank is evaluated by simulating the release of a passive scalar, using the frozen-flow field hypothesis. The results show changes in mixing times up to a factor of three when comparing MRF regions of different sizes. Thus, the present investigation highlights the importance of assessing the effect of the MRF zone size on numerical results as a standard practice in RANS based simulations of stirred-tanks.

show abstract

An experimental and numerical analysis of the fluid flow in a mechanically agitated vessel

Cited by 3 publications

References 18 publications

Impact of baffle geometry on the fluid motion in the stirred vessel

Impact of baffle geometry on the fluid motion in the stirred vessel

A General Review of the Current Development of Mechanically Agitated Vessels

CFD simulation of a Rushton turbine stirred-tank using open-source software with critical evaluation of MRF-based rotation modeling

Contact Info

Product

Resources

About