Cavazzini G.,University of Padua |
Pavesi G.,University of Padua |
Santolin A.,University of Padua |
Ardizzon G.,University of Padua |
Lorenzi R.,Research and Development Calpeda SpA
Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy | Year: 2015
A comparison between centrifugal impeller pumps with and without splitter blades in terms of suction performance is presented by experimental tests and numerical analyses. The design of both pumps was carried out by preserving the impeller meridional shape, number of blades, and volute casing. Blade shapes were obtained by adopting a 1D inverse design method. The same blade loading distribution was assumed for the full blades of both impellers, while the loading distribution of the splitter blades was modified until a close matching between the two head-capacity curves was achieved. The fulfilment of this performance requirement and the use of the same number of blades were needed to describe accurately the role played by the splitter blades in cavitation inception and development. Differently from other experimental comparisons, where previous requirements were not met, a noticeable improvement in suction performance was found at large flow rates but not at partial ones, where a small deterioration in suction performance was observed. The crucial role played by the blade thickness blockage on the incidence flow angle at the leading edge of the full blades was also investigated. © IMechE 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.