The design of the magnetic and hydraulic suspension system on an axial blood pump and the analysis of its mechanical properties

With the recent research and development trend of the third generation of artificial heart pumps, the scheme of a spiral axial blood pump with magnetic and hydraulic suspension structure was proposed. Using the bearing principle of the fluid dynamic wedge, the effect on radial hydraulic force of the blood pump rotor has been analyzed, which results from the different arc roof length of spiral blade or the different radial clearance of dynamic pressure support. The effects on axial magnetic force of the blood pump rotor has also been analyzed by using the electromagnetic analysis module of ANSYS software, which results from the different parameters of permanent magnetic bearings. The results show that the designed magnetic and hydraulic mixed passive suspension system was simple, compact and high efficient. When the blood pump rotor's rotating speed top to 6000 r/min, the stable suspension of blood pump can been realized; When its rotating speed top to 8000 r/min, the blood pump flow rate can be more than 5 L/min, which can meet the body's physiological needs.