Affiliations: Laboratoire de Mécanique des Fluides, INSA-Lyon
Bât 302, 20 av. A. Einstein, 69621 Villeurbanne, France.
Abstract: The unsteadiness of the flow at the leading edge of a vaned diffuser
represents a source of low efficiency and instability in a centrifugal pump.
Furthermore, the internal flow of the impeller can be affected by asymmetric
downstream conditions, which results in extra flow unsteadiness and
instabilities. The improvement of machine performances can only be achieved if
there is a progress in the comprehension of the nature of the complex flow that
develops at the gap between the rotor and the stator. This paper presents the
results of LDA investigation of the internal flow of a centrifugal pump
equipped with a backswept impeller and a vaned diffuser. The data taken in
phase with the impeller rotation are presented as animated frames
reconstituting a temporal evolution of the flow in radial planes at the
diffuser inlet.