Measurement of flow induced vibration of an elastic tube and its biomedical application

• Main Authors: Chi-Choung Wang, 王齊中
• Other Authors: Tian-Shiang Yang
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/31474682056207432498

碩士 === 國立成功大學 === 機械工程學系碩博士班 === 93 === ABSTRACT 　This thesis is concerned with the circulation system of human body---the cardiovascular system---and pays particular attention to the oscillatory flow phenomenon in the artery. On the basis of hemodynamic principles, here we discuss the possibility of designing a new type of bio-fluid sensor for measuring the mechanical properties of arteries non-invasively. Technically, we model the artery by an equivalent mechanical system consisting of an elastic tube conveying pulsatile fluid flow, and study the dynamic fluid--structure interaction between the tube wall and the fluid flow within. Based upon the model, we propose a methodology of measuring the mechanical properties of the equivalent mechanical system by non-invasive means. Specifically, the periodic dilation of the elastic tube wall is measured by optical sensors, and, by determining the time-delay of such measurements at two separate locations, the elastic wave speed along the tube wall is deduced. Furthermore, the Young’s modulus of the tube wall material is calculated from the wave speed, and the fluid pressure and flow rate inside the tube can then be predicted accordingly. In other words, the methodology attempts use a minimal set of input data to estimate as many unknown system parameters as possible. We have also constructed an experimental apparatus consisting of a silica elastic tube conveying water flow modulated by a solenoid valve, so that our methodology can be tested. Experimental results indicate that the methodology does yield reliable estimates of the material properties of the tube wall. The clinical adaptation of the proposed methodology is also briefly discussed in this thesis.