Numerical and experimental investigation of the 4-quadrant behavior of different mixed flow diffuser pumps

Stefan Höller*, Helmut Benigni, Helmut Jaberg

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Besides operating a centrifugal pump under normal conditions there are additional operating conditions possible; for example, a pump operated as turbine. Another example would be a pump trip where there are several abnormal operating conditions possible when the direction of flow and/or the direction of rotation are changing. The machine behavior in every possible operation condition can be represented by the complete pump characteristics, often called the 4-quadrant (4Q) behavior of a centrifugal pump. To gather the 4Q behavior, a test rig allowing the flow direction as well as the rotation direction to be reverted is necessary, with time-consuming measurements at variable positive and negative discharge in both directions of rotation the complete pump characteristics are evaluated. In the present study, an approach to investigate the complete pump characteristics by means of computational fluid dynamics (CFD) calculations is presented. With steady-state calculations and additional transient CFD investigations in the normal operating conditions, the whole pump characteristics were calculated accurately. Two different types of mixed flow diffuser pumps were investigated-one equipped with adjustable impeller blades, the second one with comparable low specific speed. Experimental verifications have shown a remarkably good agreement. Furthermore, an exemplary numerical waterhammer analysis shows the successful application of the presented approach.

Original languageEnglish
Article numberijtpp4010003
JournalInternational Journal of Turbomachinery, Propulsion and Power
Issue number1
Publication statusPublished - 7 Feb 2019


  • 4-quadrant behavior
  • Comparison of measurement and simulation
  • Computational fluid dynamics
  • Mixed flow pump
  • Model test
  • Waterhammer

ASJC Scopus subject areas

  • Mechanical Engineering
  • Aerospace Engineering
  • Energy Engineering and Power Technology


Dive into the research topics of 'Numerical and experimental investigation of the 4-quadrant behavior of different mixed flow diffuser pumps'. Together they form a unique fingerprint.

Cite this