About the Onset of Partload Instability of Swept and Unswept Axial Pump Blades

Chapter

Abstract

The partload flow field of forward, backward and unswept pump impellers was investigated in air using the hot-wire anemometry. The pump impellers were equipped on their suction side with three hot-wire anemometers at three circumferential positions with angles of sixty degrees between them allowing measurements close to the hub, the tip and in mid-channel. It was shown that each of the three cases investigated “tip stalls” and how the unstable head curve “saddle” of forward swept blades appears at a much lower flow rate then the phenomenon for unswept or backward swept blades.

Key Words

Axial flow turbomachinery blade sweep rotating stall 
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References

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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  1. 1.Institute for Hydraulic Fluid MachineryGraz University of TechnologyGrazAustria
  2. 2.BIOS BIOENERGIESYSTEME GmbHGrazAustria

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