機械心瓣穴蝕的發生,主要是於心瓣關閉時,局部流體壓力低於蒸汽壓而形成汽泡。當汽泡破裂時,其所釋放出的能量會破壞血球,產生溶血、血栓以及破壞心瓣本身的結構。穴蝕的產生是流體與結構體間交互作用的結果,但其形成的主要機制與流場和壓力的關係還未被建立起來,主要因素是心瓣的幾何形狀非常複雜,量測儀器無法進入發生源進行量測。本計畫建立一簡單之機械心瓣關閉物理模型,使得雷射都卜勒流速儀與高頻壓力計可直接量測發生源之流場與壓力以克服實驗量測上的困難,另外可將各影響因子如水錘、擠壓流效應個別加以探討,以了解穴蝕發生的機制。 Rapid leaflet closure of mechanical heart valve may create cavitation when the local pressure drops below the vapor pressure resulting in vaporous bubbles. When these bubbles collapse, the released energy may damage the structural integrity of the valve and of blood cells. Studies support the hypothesis that cavitation results from interactions between the flow field and geometric structure of the valve, but the primary mechanism of cavitation formation has not been established yet due to experimental limitations. In this study, we create a simple physical model that eliminates the complex geometry of mechanical valves and allows direct measurements via laser Doppler velocimetry and high frequency pressure transducers to further study the primary mechanism of cavitation formation. Keywords: Mechanical heart valve, Cavitation, Squeeze flow effect, Water hammer effect
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2007生物醫學工程科技研討會暨國科會醫學工程學門成果發表會論文集=Proceedings of 2007 Annual Symposium on Biomedical Engineering and Technology,頁470-473