許多的統計資料指出，心血管疾病是現代人死亡原因的前幾名，而心臟瓣膜的疾病就是其中的一種，然而目前之人工機械心瓣仍存在有穴蝕的問題，會造成血球的破壞、形成血栓。本研究利用體外脈動流循環模擬系統，裝設兩種不同的人工機械心瓣，St. Jude. Medical 29和Omniscience 29進行模擬，並以高頻率壓力計及雷射都卜勒測速儀量測其關閉時之流場狀況。由壓力量測結果發現，人工機械心瓣產生穴蝕現象之原因，並非單純由水錘效應所造成；而由雷射都卜勒測速儀的結果則發現，渦流的影響亦只佔其中之ㄧ部分。

A lot of data show that cardiovascular diseases plays an important role of death of modern people, and heart valve disease is one kind of them. Until now, implantation of mechanical heart valves still has the problem of cavitation, and it may cause blood damage and thrombosis. This study uses two kinds of mechanical heart valves St. Jude Medical 29 and Omniscience 29 with the pulsatile circularity system, and measures the flow fields during valve closure with PCB pressure sensor and laser Doppler velocimetry. The result shows that only water hammer effect or the vortex would not be strong enough to cause cavitation.

目錄	I
圖目錄	III
表目錄	V
第一章  緒論	1
1-1 前言	1
1-2 研究動機及目的	3
1-3 研究過程	5
第二章  文獻回顧	7
2-1 人工機械心瓣	7
2-2 穴蝕(Cavitation)的成因	11
2-3 水錘效應與渦漩之研究	17
第三章  實驗設置與方法	21
3-1體外脈動流模擬循環系統	21
3-2 壓力計	26
3-3雷射都卜勒流速儀(Laser Doppler Velocimetry, LDV)	27
3-4 資料擷取與分析	35
3-5 實驗條件及量測位置	37
第四章 結果與討論	40
4-1 主動脈壓與左心室壓力波形	40
4-2心瓣兩側之PCB壓力波形	43
4-3心瓣中央斷面之速度場	48
4-4 壓力、渦流與穴蝕之相關性	53
第五章 結論	55
參考文獻	57
附錄A	60

圖目錄
圖1 - 1 研究流程示意圖	6
圖2 - 1 Starr-Edwards, 1966	9
圖2 - 2 Bjork-Shiley tilting disk, 1969	9
圖2 - 3 Medtronic-Hall Standard, 1977	9
圖2 - 4 Omniscience, 1977	10
圖2 - 5 St. Jude Medical, 1977	10
圖2 - 6 Lapeyre et al., 2002	10
圖3 - 1 模擬循環系統	23
圖3 - 2 系統架構圖	24
圖3 - 3 線性馬達	25
圖3 - 4 左心室與左心房	25
圖3 - 5 高頻率壓力計PCB	26
圖3 - 6 雷射都卜勒流速儀(LDV)	27
圖3 - 7 LDV量測體積示意圖	29
圖3 - 8 自行撰寫分析AD卡的程式	35
圖3 - 9 PCB量測位置示意圖	38
圖3 - 10 LDV量測斷面示意圖	39
圖3 - 11 量測點位置分佈示意圖	39
圖4 - 1 Omniscience的生理波形	41
圖4 - 2 St. Jude Medical的生理波形	42
圖4 - 3 Omniscience的PCB壓力波形	44
圖4 - 4 St. Jude Medical的PCB壓力波形	45
圖4 - 5 速度沿時間分佈代表圖	48
圖4 - 6 Omniscience之circulation分佈圖	49
圖4 - 7 St. Jude Medical之circulation分佈圖	50
圖4 - 8 Omniscience於gap點之circulation統計代表圖	51
圖4 - 9 SJM於gap點之circulation統計代表圖	52

表目錄
表2 - 1 渦漩中心點預估之壓降	16
表3 - 1 雷射光源之光學參數	34
表4 - 1 Omniscience的PCB壓力量測結果	46
表4 - 2 St. Jude Medical的PCB壓力量測結果	46
表4 - 3 Omniscience之circulation計算結果	49
表4 - 4 St. Jude Medical之circulation計算結果	50

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