In this paper, the aerodynamic design of a bowl–type diffuser for a low specific–speed pump is presented and described in detail. The main goal was to achieve an optimal configuration in terms of diffuser recovery capacity and stage aerodynamic efficiency, while satisfying severe constraints concerning stage size and multistage feasibility. Both geometrical parametrization tools and a fully–viscous three–dimensional numerical solver were exploited in the design process. The geometrical parameterization allowed one to control and modify the geometry of the component by changing a limited number of parameters. CFD analysis was exploited to assess the effectiveness of the geometrical modifications on the performance, and to identify critical problems. A number of aerodynamic ID coefficients with simple physical meanings were also introduced and used as a support to the design to synthesize the main feature of the strongly three–dimensional flow evolving in the component. As a result, a new stage configuration was developed according to the imposed constraints, whose performance is at the same level as standard pumps of the same class.
Bowl-Type Diffusers for Low Specific-Speed Pumps: An Industrial Application / Paolo Boncinelli;Roberto Biagi;Antonio Focacci;Umberto Corradini;Andrea Arnone;Marco Bernacca;Massimiliano Borghetti. - ELETTRONICO. - 2: Automotive Systems, Bioengineering and Biomedical Technology, Fluids Engineering, Maintenance Engineering and Non-Destructive Evaluation, and Nanotechnology:(2006), pp. 667-676. (Intervento presentato al convegno ASME 8th Biennial Conference on Engineering Systems Design and Analysis tenutosi a Torino, Italy nel July 4–7, 2006) [10.1115/ESDA2006-95248].