Steady And Unsteady Numerical Simulation Of Internal Flow Field In Entrifugal Cardio Pump

With the development of technology and economy, more and more heart patients turn to use the artificial cardio pump in place of the natural heart. As a new artificial heart pump,the centrifugal cardio pump has advantages of small volume, high reliability and less impairment to blood etc.The research of the centrifugal cardio pump is very important for the development of cardio pump.Steady and unsteady numerical simulations for the centrifugal cardio pump which are designed by unitary theory were done by CFD.The paper analyzed the distribution of internal flow field of centrifugal cardio pump and revealed the special rules and flowing mechanism of internal flow.The distribution of pressure field, velocity field, velocity vector and shear stress etc in different speed and flow of centrifugal cardio pump were analyzed using steady and unsteady simulations, which lay a good foundation for improving the performance the centrifugal artificial cardio pump and the ability of antithrombotic and hemolysis.This paper makes a thorough review of research on the artificial heart pump at both home and abroad, expounded the basic theory of CFD,and introduced the model and numerical computation method in the simulation using the CFD software.Three-dimensional models of the flow passage were created by Pro/E, and transferred directly into ICEM to generate mesh.The non-uniform tetrahedral meshes were used to divide the flow region. Effect of numbers and quality of the meshes on the numerical solution was analyzed.All the meshes file were imported into the fluid simulation software-FLUENT, and then the fluid parameter and boundary conditions were set, the RNG Κ-ε turbulent model and pressure coupling arithmetic were used to solve the equation.At last, the steady and unsteady numerical simulations for the cardio pump were realized.By numerically simulating the cardio pump under different working conditions,the characteristic curves of centrifugal cardio pump were got as well as its distribution conditions of internal pressure, velocity,and shear stress etc.The unsteady simulation was done under the design condition of the cardio pump, the axial force, radial force and the distribution of pressure and velocity were researched, which unveiled the unsteady influence of the static and dynamic disturbance of the impeller and the volute generates on the fluid in centrifugal cardio pump.The simulation results are in the good agreement with the theoretical research.The results provided reference for later research and the selection for the centrifugal cardio.