Characteristic Outflow Boundary Conditions for Simulations of One- Dimensional Hemodynamics
نویسنده
چکیده
The Windkessel outflow models, describing the relation between blood pressure and flow, are commonly used for modeling the truncated downstream vasculature bed in the arterial system. By means of a characteristic approach, a unified formalism of characteristic boundary conditions was proposed in the present work. A novel defined parameter, termed the reflection coefficient, is convenient to quantify and analyze the incoming waves occurring at the boundary of the computational domain. Numerical examples using different forms of outflow models including one-, two-, and three-element Windkessel models were studied and discussed. The results indicate that when the 1-D terminal ends are coupled with the three-element Windkessel outflow model, the system is able to capture the physiological features. Keywords— Windkessel models, reflection coefficient, hyperbolic system, distributed arterial network, nonreflecting boundary condition.
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