Amirkabir Journal of Mechanical Engineering

Amirkabir Journal of Mechanical Engineering

Influence of Blade Outlet Angle on the Inverse Design Method for Centrifugal Pump Impellers

Document Type : Research Article

Author
Abdollah Eskandari
Payame Noor University - Faculty of Engineering
10.22060/mej.2026.25139.7924
Abstract
This research explores the impact of blade outlet angle on the inverse design methodology of centrifugal pump impellers, aiming to enhance hydraulic performance through improved flow control and reduced secondary losses. The inverse design approach is employed to regulate blade loading and achieve a more uniform pressure distribution at the impeller outlet, thereby optimizing efficiency and head generation. Blade geometries were generated using vorticity-based modeling combined with inviscid slip boundary conditions to minimize tangential pressure gradients and suppress secondary flow structures. Three outlet angles—0°, +45°, and –45°—were imposed as boundary conditions in the design process. The resulting impeller configurations were evaluated using computational fluid dynamics (CFD) simulations and validated against experimental data. The results demonstrate that a negative outlet angle (–45°) significantly improves flow uniformity, reduces tangential pressure gradients, and weakens secondary vortices, leading to a hydraulic efficiency increase of up to 8.5% and a head rise of approximately 3.2 meters at the design operating point. These findings highlight the critical role of outlet angle selection in inverse blade design and its potential to improve turbomachinery performance. The study provides a robust framework for integrating geometric optimization into pump design strategies, offering practical insights for engineers seeking to enhance energy efficiency and operational reliability in fluid transport systems.
Keywords
Centrifugal Pump
Inverse Design
Blade Outlet Angle
CFD
Subjects
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Amirkabir Journal of Mechanical Engineering
Volume 57, Issue 12
March 2026
Pages 1601-1618