浅谈动脉流体动力学分析

就我们所熟知，绝大部分正常动脉流，其血液的流动特性是属于层流范围，但随着弯曲和分 支部分会产生血液流之二次回流区，进而形成所谓近似非稳态流及紊流. 因此动脉流体的特 性会随动脉外形及条件的改变而改变. 在某些情形下，异常动脉的血液动力特性会造成动脉 的病变. 因此，近年来动脉血液流体的特性的研究，常着重于异常动脉的血液动力特性所形 成剪应力和病变部位动脉粥状硬化关系的探讨. 动脉血液流动经常包含分离流或二次回流运动，而这是流体力学的分析或数值模拟最困难的 部分. 有关分离流或二次回流的研究包括正常血管流和异常血管流，藉由二次回流的模拟与 测量可以观察血管病变的形成与演变，其中最受注目探讨题目是窄化血管如粥状斑块相关的 血液流动分析. 将回顾二维和三维、稳态、非稳态之动脉血流与窄化血管相关的几何外形作模拟研究和 实验. 并提供对血液动力学的研究方向，以作为未来医疗诊断与发展相关器材之参考.

A NOTE ON THE STUDIES OF ARTERIAL FLOW MECHANICS

As we know, the regular arterial flow is in the laminar flow regime. The blood flow properties, particularly, the shear stresses along the blood vessel, and the sites where atherosclerosis develops, have attracted tremendous researches in recent decades. It has been well known that the oscillating and low shear stresses play an important role in the development of vascular lesions. Unsteady irregular stress distributions are likely to prevail at the curved and bifurcated vessels with side branches, where, due to complicated geometries, blood flows always contain flow separation or secondary motions difficult to be simulated and understood in fluid mechanics. In this paper, the past studies on the transient multi-dimensional blood flows in arterial stenosis or in arterial geometries relevant in the conditions of atherosclerosis are reviewed. We also make suggestions for the future possible studies of circulatory vascular flows and wish to provide some food for though for further designs of bio-medical devices.