Pumping Capacity of Pitched Blade Multi-Stage Impellers

• Authors: Tomáš Jirout
• Languages of publication: EN

Abstracts

EN

This paper extends knowledge about flow in an agitated batch with pitched blade multi-stage impellers. Effects of various geometrical parameters (blade number, distance between impellers) of pitched blade multi-stage impellers on pumping ability have been investigated. Axial velocity profiles were measured by LDA (Laser Doppler Anemometry). Axial pumping capacities were obtained by integration of measured axial velocity profiles in outflow from impellers. Main attention was focused on the effect of the distance between impellers in multi-stage configurations, on their pumping capacity and flow in the mixing bath in comparison with an independently operating pitched blade impeller with the same geometry. In case of a relatively close distance between impellers H3/d = 0.5 - 0.75, the multi-stage impeller creates only one circulation loop and the impellers itself behave identically as pumps in series. However for relative higher distance of impellers than H3/d = 1.25, the multi-stage impeller creates two separated circulation loops.

Keywords

EN

pitched blade impeller; multi-stage impeller; impeller pumping capacity; velocity profile; laser Doppler anemometry

• Publisher: De Gruyter Open
• Journal: Chemical and Process Engineering
• Year: 2014
• Volume: 35
• Issue: 1
• Pages: 47-53

Dates

published

1 - 3 - 2014

received

18 - 2 - 2013

online

25 - 4 - 2014

accepted

5 - 12 - 2013

Contributors

author

Tomáš Jirout

• Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Process Engineering, Technicka 4, 166 07 Prague 6, Czech Republic

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Identifiers

DOI

10.2478/cpe-2014-0004