| Blood pump is a small pump that can completely or partially replaces heart function andmaintains normal body blood circulation. It is very important for patients with heart disease.Current blood pump is mainly rotary impeller structure that can be implantable, and theaxial-flow structure is the most representative. The working principle of blood pump decides thatit needs a high speed to meet the human body blood pressure, but higher speed causes greaterdamage to the blood and easy to cause hemolysis.In order to solve this problem,the blood pump is designed by using two-stage axialstructure.The front impeller is designed to helico-axial structure by using one dimension flowand rear impeller is designed to traditional axial structure by using streaming design method.Detailed works of this paper are as follows.(1)According to the design plan, the structure design of two-stage blood pump mainlyincludes design of the rotor head and tail, selection and design of the front impeller and rearimpeller, determination of correction value of rear impeller blade airfoil placed angle as well asthe relative position of front impeller and rear impeller;(2)Space coordinate points of rear impeller blade airfoil are calculated by writing Malabprogram, and then combined with Pro/E drawing capabilities, accurate3D model of two-stageblood pump is established;(3)Gambit is used to mesh the3D model and Fluent is used to calculate the mesh model andfinally simulation results are used to do detailed analysis of two-stage blood pump’s workingcondition, stress distribution, pressure distribution, speed distribution and turbulence effects. Theanalysis results show that: in the same conditions, compared with single stage structure bloodpump, the maximum stress of two-stage structure blood pump decreases significantly and thestructure is good to reduce the formation of hemolysis effectively. |
