Experimental investigation of a multiple disk centrifugal pump

The paper presents an experimental investigation of the characteristics of a centrifugal pump equipped with a multiple disks rotor specifically designed to operate in the optimal flow regimes. Global measurements are carried out with controlled accuracy while the machine is processing an highly viscous Newtonian lubricating oil in a closed loop system. Results, presented in non dimensional form, indicate that the work transfer is truly efficient, and leads to stable flow conditions all across the performance map. Rotor efficiencies in excess to 80% are measured in a wide range of flow coefficients, thus demonstrating that the theoretical achievements of the late 70s pertaining to the single pair of co-rotating disks can be attained in a true machine environment, provided the optimal wheel flow conditions are preserved. Overall pump efficiency is penalized by inadequate diffusion systems, and not by rotor work transferring mechanisms.