全分支的体循环混合参数计算机模拟研究

The Computer Simulation of Hybrid Parameter Systemic Circulation Model Including Arterial Branch

本文提出了一种改进的人体血液动脉系统的计算机模拟方法，即把动脉血流脉搏波传播的非线性（或线性）分布参数模型与线性集中参数流体网络模型混合，构造动脉系统的分布─集中混合参数模型。对模型中分布参数部分，采用非标准Ｇａｌｅｒｋｉｎ半离散空间有限元方法进行处理．通过具体建立人体体动脉系统的这种混合参数模型、并进行计算机模拟研究，结果表明，这种模拟方法既可以从系统的量级上模拟动脉系统的血流动力学特性，又可以对所感兴趣的局部血管处进行较细致的模拟，并且可以研究系统各部分间的相互影响。

Modeling arterial system hemodynamic performances has long been of interest, but the development of realistic models has only occurred in realtively recent times. Causes for the slow progress include nonlinearities in the model equations, unsteady now in the vascular system, and viscoelastic properties of arteries. However, the rapid developmtent of digital computers has made numerical solutions to this type of complex problem feasible, and this approach is now commonly used.In the present study , a king of hybrid parameter arterial system computer model is presented. The nonstandard Galerkin finite-element method is used to simulate pulsatile flows in some arterial segments, which may contain localized constrictions, taper and branches. And the other parts of the arterial system are described using lumped parameter models.Specifically. the purposes of the study are: 1) to develop an arterial system model allowing for arterial taper, obstructions and branches ; 2) to apply the medel to study the hemodynamic performances of the entire arterial system in the normal and diseased conditions ; 3) to study the influences on each other of different parts of the system,and to demonstrate how a model of the arterial system suffering from pathological constrictions may provide useful information relative to techniques used in the diagnosis of obstructive arterial disease.The results of the computer simulation show that this kind of model can be utilized to study both the arterial system hemodynamic performances and the influences on the system of arterial stenosis, taper I branches and others. The reactions, among the different parts of the system, can be explored at the system level with this model.