Dear vnardone,
Hello, this is an eternal, interesting question you have raised. No, it is not normal for a pump not to achieve its specified performance. However, a systematic approach is required to determine success or failure of the pump.
First & foremost, pl. clarify whether the purchase...
Choice of radial or mixed flow impellers depends on the specific speed (ns = n * Q**0.5/ H**0.75) of pump stage. Upto about 1500 rpm(USGPM based) specific speed radial impeller design is the best and we should go for mixed flow impeller for specific speed (USGPM based) from 1500 rpm to 8000 rpm...
How is NPSHR of an Axial Flow/ Propeller pump estimated from the impeller design? We know that NPSHR for pumps in general will be dependent on tip speed, meridional flow velocity and angle incidence at inlet. For designs using airfoil shaped impeller blades, how are these and any other...