紊流剪力流場中溶血效應的研究

由於血液流經人工器官時，紅血球受到非生理流況產生應力使其外膜破裂，釋放出血紅素到血漿中。而血漿中的自由血紅素是含有毒性的，會造成腎臟及其他器官的衰竭，因此在研發人工器官時，都不期望血球遭受到破壞而引發溶血。故本實驗利用噴射流來形成紊流場，流場量測則使用數位質點影像測速儀，得知流場的分佈，再將清洗過的血球置入流場中進行溶血實驗。雷諾應力及黏滯切應力常被用來估算溶血，因此引用過去學者所做的研究進行驗證的工作。雷諾應力跟隨Sallam[3]所做的實驗，驗證了雷諾應力值為400Pa時血球會遭受到破壞，但本實驗經過主軸平面的轉換後雷諾應力的閥值應為718Pa。而黏滯切應力則利用Sheng[31]與Jones[23]兩種方法進行分析，本實驗做出來的數據計算出來的黏滯切應力大小均符合Jones的研究結果。

關鍵字

溶血；噴射流；數位質點影像測速系統；雷諾應力；黏滯切應力

並列摘要

When blood passes through the artificial organ, membranes of red blood cells crack due to the shear stress generated by nonphysical flow condition, thus hemoglobin are released from red blood cells and flow into plasma. These free hemoglobin in plasma are toxic. They may cause kidneys or other organ failures. Therefore, under the research and development process of artificial organs, preventing the destruction of blood cells that can lead to hemolysis is certainly the top priority. For this reason, this study aims to create turbulence fields by means of a jet flow, and measure the distribution of flow field and turbulent stresses by using digital particle image velocimeter (DPIV). The washed porcine blood cells are then put into the flow field to do the hemolytic experiment. The thresholds of the Reynolds shear stress and viscous shear stress are usually put to use to measure the hemolysis. In comparision with previous researchers, this study well compare with that of Sallam and Hwang[1] measured the Reynolds shear stress in free turbulent jet flow and reported values of 400 N/m2 .However, in this study Reynolds shear stress is at 718 N/m2 after the shift between principal axis and plane. Moreover, The viscous shear stress is used Sheng[31] and Jones[23] are two ways to analyze the data from this experiment, the quantity of viscous shear stress confirm the results of Jones’s study.

並列關鍵字

hemolysis ； jet flow ； DPIV ； Reynolds shear stress ； viscous shear stress

參考文獻

[6] 林志誠,2009,”雷諾應力對溶血效應研究,”淡江大學水資源及環境工程學系碩士論文.

[1] Sallam, A. H., and Hwang, N. H. C., 1984, ”Human red blood cell hemolysis in turbulent shear flow: Contributions of Reynolds shear stresses,” Biorheology, Vol.21, pp. 783-797.

[2] Beaver, G.. S. and T.A.Wilson, 1970,”Vortex growth in jets,” Journal of Fluid Mechanics, Vol.44,pp.97-112.

[3] Sallam,A.M.,1982.”An investigation of the effect of Reynolds shear stress on red blood cell hemolysis.,” PhD thesis.

[5] Yule,A.J.,1978,”Large-scale structure in the mixing layer of a round jet,” Journal of Fluid Mechanics,Vol.89,pp.413-432.

國際替代計量

紊流剪力流場中溶血效應的研究

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