摘要
心血管流体力学以心血管系统中血液的流动与血管壁的变形作为研究对象，是一门应用于血液循环系统的耦合力学。国内外对这一领域的研究主要为血液在血管内流动的流速及流量，以及血管内流体流动的非线性动力学分析和对血管力学性能的探讨。而大部分研究都没有涉及到狭窄血管管壁的变形与应力分析，以及狭窄处植入支架后血管壁的变形与应力分析。因此，有关动脉局部狭窄的形成、发展、对血液流动的影响方面以及如何正确安放支架的研究是心血管流体力学当前重要的研究课题之一。
本文主要应用心血管流体力学基本理论知识，着重求解狭窄血管管壁的变形与环向应力。其研究目的在于为心血管疾病在临床治疗中提供科学的理论依据。
根据流体弹性力学基本理论知识，在对血液流动的Navier-Stokes方程与动脉管壁运动方程进行简化的基础上，导出动脉中脉动流的基本方程。通过对这些方程的求解，求出了血液流动速度及脉搏波压力表达式。并详细地讨论了脉搏波在一个心动周期内血管狭窄程度不同时，血管狭窄处植入支架前、后血管壁的变形与环向应力的变化。并用MATLB绘制了一系列的关系曲线。给出了在不同狭窄程度时，安放支架所需的支撑力的计算方法和计算结果。讨论了狭窄处正确安放支架的一些条件和参数。
通过研究得知：影响狭窄血管管壁变形和环向应力大小的因素有血管壁的弹性模量、厚度、血管的半径、局部狭窄的程度、局部斑块的硬度等。本文的研究结果可供临床上对狭窄血管植入支架后的变形与受力分析，和支架的正确安放参考，可避免发生堵塞严重或血管钙化时，由于安放支架不当而使发生血管破裂的医疗事故。
Cardiovascular fluid mechanics to cardiovascular system in the flow of blood andblood vessel wall deformation as the research object, is a used in blood circulationsystem coupling mechanics. Home and abroad of this research field in cardiac cycle ismainly for blood in veins of the flow velocity and flow rate, nonlinear dynamic analysisand numerical simulation of fluid flow in a local narrow tube, and mechanical propertiesof blood vessels. Most of these researches are not involved in the research of the bloodvessels to narrow wall deformation, stress analysis, and blood vessel wall deformationand stress analysis on the narrow part of stent after being implanted. Therefore, the localstricture formation, development, the effects on blood flow and correct installation of thecardiovascular artery, are important parts of fluid mechanics research
This paper focuses on the narrow wall vessels to solve deformation and hoop stressstate with elementary theory knowledge of cardiovascular fluid mechanics. The objectiveof the study is that for cardiovascular disease in the clinical treatment to providescientific theory.
According to the theory of knowledge, the arteries of the pulse derived flow basicequations is studied based ob simplifying Navier-Stokes equation and the artery wallmotion equation. Through analyzing the solution of the equation, blood flow velocity andpulse pressure formula are observed. This paper discussed in detail the blood vessel walldeformation and the change of hoop stress, while before and after stent, and the pulsewave in a cardiac cycle with various stenosis degrees. A series of relation curves aremapped by using MATLB. In different narrow degree, the calculation method and theresults of support are gained，and also discussed the conditions and parameters ofcorrectly stent.
Through this research, influence reason on narrow vascular wall deformation and tothe size of hoop stress is studied as follows: the factors of the blood vessel wall elasticmodulus, thickness, blood vessels, and the extent of the local stricture radius, localpatches of hardness, etc. The results studied in this paper are for clinical research of blood vessels deformation and stress analysis after stent, and correct installation ofsupport, thus can avoid serious blocking or vascular rupture, which dues to improperstent when vascular calcification.
引文
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