Best Practice Advice AC7-03: Difference between revisions
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=Best Practice Advice= | =Best Practice Advice= | ||
==Key Fluid Physics== | ==Key Fluid Physics== | ||
When calculating blood flow through complex medical devices, it should always be kept in mind that blood is a non-Newtonian, multiphase fluid. However, in simulations in ventricular assist devices, blood is approximated as a Newtonian, single-phase fluid. The former is justified because blood has asymptotic viscosity under high shear rates. In the latter, a blood-analogous fluid is assumed, which has comparable density and viscosity to blood. This assumption is necessary because it is impossible with current computational technology to account for the multiphase character of blood in a VAD simulation. This is partly due to the fact that the dimensions of the blood components are much smaller than the vortex structures calculated by the simulation. Therefore, much larger computational grids than in the current literature are needed to accommodate the blood components (size order of erythrocytes ≈ 10-6 m) to be integrated in the simulation. | |||
==Application Uncertainties== | ==Application Uncertainties== | ||
==Computational Domain and Boundary Conditions== | ==Computational Domain and Boundary Conditions== | ||
Revision as of 12:40, 15 December 2021
Turbulent Blood Flow in a Ventricular Assist Device
Application Challenge AC7-03 © copyright ERCOFTAC 2021
Best Practice Advice
Key Fluid Physics
When calculating blood flow through complex medical devices, it should always be kept in mind that blood is a non-Newtonian, multiphase fluid. However, in simulations in ventricular assist devices, blood is approximated as a Newtonian, single-phase fluid. The former is justified because blood has asymptotic viscosity under high shear rates. In the latter, a blood-analogous fluid is assumed, which has comparable density and viscosity to blood. This assumption is necessary because it is impossible with current computational technology to account for the multiphase character of blood in a VAD simulation. This is partly due to the fact that the dimensions of the blood components are much smaller than the vortex structures calculated by the simulation. Therefore, much larger computational grids than in the current literature are needed to accommodate the blood components (size order of erythrocytes ≈ 10-6 m) to be integrated in the simulation.
Application Uncertainties
Computational Domain and Boundary Conditions
Discretisation and Grid Resolution
Physical Modelling
Recommendations for Future Work
Contributed by: B. Torner — University of Rostock, Germany
© copyright ERCOFTAC 2021