Studies of mixing time and momentum transfer for an agitated with an off-centred impeller

Karcz, J.; Cudak, M.; Szoplik, J.

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Tytuł artykułu

Studies of mixing time and momentum transfer for an agitated with an off-centred impeller

Autorzy

Karcz J. , Cudak M. , Szoplik J.

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Abstrakty

In many industrial processes, the final technological effect related to the product quality strictly depends on the efficiency of agitation. The effects of the impeller eccentricity and liquid pumping mode of the impeller on the liquid homogenisation and momentum transfer processes are discussed in the paper. The mixing time tm in an un - baffled agitated vessel of working volume V = 0.27 m^3 was measured using thermal method. The dimensionless shear rate gamma/n and friction coefficient f on the cylindrical wall of the vessel of the volume V = 0.022 m^3 were determined by means of an electrochemical method. The distribution of both gamma/n and f values is found as a function of the impeller eccentricity eR for a propeller and HE 3 impeller. The data for dimensionless mixing time were correlated using Eq. (1). The values of gamma/n and f, averaged for the whole cylindrical wall, were described for both the propeller and HE 3 impeller, by means of Eqs. (2) - (5).

Słowa kluczowe

agitation shaft eccentricity homogenisation shear rate friction coefficient

mieszanie mieszadło niecentryczne homogenizacja szybkość ścinania współczynnik oporu

Wydawca

West Pomeranian University of Technology. Publishing House

Czasopismo

Polish Journal of Chemical Technology

Rocznik

2006

Tom

Vol. 8, nr 1

Strony

35--42

Opis fizyczny

Bibliogr. 23 poz., tab., rys.

Twórcy

autor

Karcz J.

autor

Cudak M.

autor

Szoplik J.

Szczecin University of Technology, Institute of Chemical Engineering and Environmental Protection Processes, al. Piastów 42, 71-065 Szczecin, joanka@ps.pl

Bibliografia

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(11) Karcz J., Szoplik J.: An effect of the eccentric position of the propeller agitator on the mixing time. Chem. Pap., 2004, 58, 1, 9 - 14.
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(13) Szoplik J.: The studies of the mixing time in a stirred tank with an eccentrically located impeller. PhD Thesis, Szczecin University of Technology, 2004.
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(16) Cudak M.: Heat and momentum transfer in a stirred tank with an eccentrically located impeller. PhD Thesis, Szczecin University of Technology, 2004.
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Bibliografia

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