Hydraulic development of a centrifugal pump impeller using the agile turbomachinery design system

The impeller of an existing industrial pump (with both geometry and performance known) was analyzed and redesigned using an integrated, design/analysis, turbomachinery geometry modeling and flow simulation system. The purpose of the redesign was to achieve improved impeller performance (at the duty point). Fluid dynamics and geometry modeling parts of the design/analysis system were systematically applied: a) to analyse the existing impeller (impeller A), which was designed using conventional (routine in industry) hydraulic layout procedures, and b) to develop a new impeller (impeller B), using a coupled, multilevel 1D-Q3D-3D for the design and optimization. This paper discusses the features and advantages of the integrated design system, in which the coupled CAD/CFD approach is fully implemented. The analysis results are presented for impellers A and B, with the latter demonstrating a predicted increased efficiency and smaller size. Comparisons of the CFD results for both impellers reveal internal flow features that explain the improved impeller B performance levels.