拉伸流所產生之局部消散能量與溶血相關研究

Hemolysis as a function of the local energy dissipation created by a rapid extensional flow

邱奕銘(Yi-Ming Chiou)

指導教授 ： 盧博堅

淡江大學/工學院/水資源及環境工程學系碩士班/碩士(2014年)

https://doi.org/10.6846/TKU.2014.00980

摘要

隨著社會與生活型態的日新月異，因此人類的飲食習慣與生活作息也有所改變，但這同時對身體的器官造成相當大的負擔，也使得病變越來越多樣化，人類為了改善這些病狀，研發出人工心血管器官。但心血管中會造成非生理性的流況，其流況所產生的血流應力會引發血液的破壞，特別是紅血球的損傷，稱為溶血。真實流場應包含有剪應力和拉伸應力，許多學者在爭論切應力和拉伸應力何者才是主導溶血的主要因素，於是產生了一個指標也就是能量消散率，這個指標無忽略上述兩種力，本研究以斜角模型與直角模型做為實驗流場，探討這三種力何者才是主導溶血主要因素，此流場先經由CFD的計算，求出其應力值，然後採用豬的新鮮紅血球，進行溶血的測試，發現切應力與能量消散率無法成為主導溶血的主要依據，而拉伸應力才是主導血球破壞的主導血球破壞的機械力，其閥值約為800 Pa。

關鍵字

溶血 ； 切應力 ； 拉伸應力 ； 能量消散率 ； 計算流體力學 ； 心血管系統

並列摘要

With newer and newer society and life style, the diet and living habits of people are also changing, but they make a great burden to organs in our body simultaneously. They also make more pathological changes. Therefore, humans develop artificial organs of cardiovascular to improve these symptoms.
However, there is irrational flow conditions in cardiovascular system. What’s more, flow conditions will cause stress and destroy blood, especially in destruction of red blood cell, which is called hemolysis. Real flow field should include shear stress and extensional stress. Many scholars argue that which one is the main hemolysis factor, so they use Energy Dissipation Rates as an indicator. Energy Dissipation Rates don’t disregard foregoing two stress. This research apply bevel model and right Angle model to be a experimental flow field, discussing which one is the main hemolysis factor. Flow field is calculated by CFD and get stress of threshold. Then, I use pig’s fresh red blood cell to test hemolysis. I find that Shear stress and Energy Dissipation Rates can’t be the main factor in hemolysis. Nevertheless, according to 800 Pa threshold value, I find that extensional stress can destroy blood cells, and it is also the main factor.

並列關鍵字

hemolysis ； shear stress ； extensional stress ； energy dissipation rates ； CFD ； cardiovascular system

參考文獻

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