Vortex depth in mixed unbaffled vessels

Rieger, F.; Ditl, Pavel; Novák, V.

doi:10.1016/0009-2509(79)85073-3

Cited by 46 publications

(18 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…1 constants of integration in Eqs (6) and (14) vessel diameter impeller diameter acceleration due to gravity static liquid level impeller clearance (see Fig. 1 …”

Section: Critical Impeller Speedmentioning

confidence: 99%

Vortex depth in unbaffled single and multiple impeller agitated vessels

Markopoulos

Kontogeorgaki

1995

Chem Eng & Technol

View full text Add to dashboard Cite

Although vortex formation is usually an undesirable phenomenon in the process industry, satisfactory process conditions and results can also be obtained in unbaffled agitated vessels in the presence of a vortex. This fact and especially the low power requirements in these systems, with their immediate relevance to the energy problem in the process industry, show the true importance of vortex formation in agitated vessels. This article reviews the literature results and the correlations proposed for the prediction of vortex depth in unbaffled agitated vessels with various types of single and multiple impeller systems and presents a critical discussion on the basis of a theoretical analysis.

show abstract

“…1 constants of integration in Eqs (6) and (14) vessel diameter impeller diameter acceleration due to gravity static liquid level impeller clearance (see Fig. 1 …”

Section: Critical Impeller Speedmentioning

confidence: 99%

Vortex depth in unbaffled single and multiple impeller agitated vessels

Markopoulos

Kontogeorgaki

1995

Chem Eng & Technol

View full text Add to dashboard Cite

show abstract

“…Experiments conducted by Reiger et al 20 and Zlokarnik 19 have the rotor deep in the tank, whereas in the present experiments the rotor is placed near the water surface. The correlations developed in (11) and (12) are for geometrically similar systems.…”

Section: Vortex Depth Correlation For Surface Aeration Tankmentioning

confidence: 83%

“…In dimensionless form, V d /d is a function of just Fr and the Galileo number, Ga ≡ Re 2 /Fr, where Re is impeller Reynolds number and equals N d 2 /ν. This relationship (the relation of vortex depth with Ga and Fr) helps when scaling up the surface aeration tanks 19,20 .…”

Section: Theoretical Considerationsmentioning

confidence: 99%

See 1 more Smart Citation

Untitled

Rao¹,

Kumar²,

Patel³

2009

ScienceAsia

View full text Add to dashboard Cite

Agitating liquids in an unbaffled surface aeration tank leads to the formation of a vortex in the region of the impeller shaft. The types and characteristics of the vortex govern the process phenomena of a surface aeration tank. In the present work, experimental results and empirical correlations have been obtained to relate the vortex depth to a number of physical factors. Experiments have been carried out on geometrically similar surface aeration systems, so that the present results can be simulated in the field conditions. The critical speed at which the vortex reaches the impeller has been estimated. It is found that around critical speed, there is an observable change in mass transfer characteristics, power used for mixing, and radius of the forced vortex zone. Equations for predicting vortex depth in geometrically similar surface aeration tanks have also been developed.

show abstract

“…For the food and pharmaceutical industries it is a matter of primary importance to keep the reactor, as clean as possible; in crystallization processes [10] and biological applications [11] shear and impact are to be minimized; in precipitation processes baffles may suffer from incrustation problems [12]. Scientific literature shows an increasing interest in experimental investigations towards unbaffled stirred vessels [13][14][15][16][17][18][19][20][21][22][23][24][25] showing better potential for some industrial use of such type of stirred reactors. Brucato et al [22] found minimum power requirements for complete suspension in top-covered unbaffled vessels which are less than from corresponding baffled tanks.…”

Section: Introductionmentioning

confidence: 99%

Vortex Depth Analysis in an Unbaffled Stirred Tank With Concave Blade Impeller

Devi¹,

Kumar²

2017

ChChT

View full text Add to dashboard Cite

Abstract. 1 The present study was carried out by experimenting in a stirred tank of unbaffled system employed with concave blade impeller. In this study the influence of impeller diameter (d), tank diameter (D) and impeller clearance depth ( C ) on vortex depth is investigated at various impeller rotational speeds. The higher vortex depth is observed when the impeller is closer to the tank bottom. Relative vortex depth increases with the increase in the impeller diameter in all cases of impeller clearance depth at constant D. Smaller tank diameter gives higher relative vortex depth, when d is constant at different impeller clearance depths. Critical speed is found decreasing with the increase in C/D and d/D ratio. Finally, a scale up criteria for relative vortex depth has been developed, which is valid for geometrically similar conditions.

show abstract

Vortex depth in mixed unbaffled vessels

Cited by 46 publications

References 3 publications

Vortex depth in unbaffled single and multiple impeller agitated vessels

Vortex depth in unbaffled single and multiple impeller agitated vessels

Untitled

Vortex Depth Analysis in an Unbaffled Stirred Tank With Concave Blade Impeller

Contact Info

Product

Resources

About