Estimation of Viscous Dissipative Stresses Induced by a Mechanical Heart Valve Using PIV Data
學年 98
學期 1
發表日期 2009-12-18
作品名稱 Estimation of Viscous Dissipative Stresses Induced by a Mechanical Heart Valve Using PIV Data
作品名稱（其他語言）
著者 Lu, Po-chien
作品所屬單位 淡江大學水資源及環境工程學系
出版者 Lippincott Williams & Wilkins
會議名稱 ASAIO 55rd Anniversary Conference
會議地點 Dallas, USA
摘要 Among the clinical complications of mechanical heart valves (MHVs), hemolysis was previously thought to result from Reynolds stresses in turbulent flows. A more recent hypothesis suggests viscous dissipative stresses at spatial scales similar in size to red blood cells may be related to hemolysis in MHVs, but the resolution of current instrumentation is insufficient to measure the smallest eddy sizes. We studied the St. Jude Medical (SJM) 27 mm valve in the aortic position of a pulsatile circulatory mock loop under physiologic conditions with particle image velocimetry (PIV). Assuming a dynamic equilibrium assumption between the resolved and sub-grid-scale (SGS) energy flux, the SGS energy flux was calculated from the strain rate tensor computed from the resolved velocity fields and the SGS stress was determined by the Smagorinsky model, from which the turbulence dissipation rate and then the viscous dissipative stresses were estimated. Our results showed Reynolds stresses up to 80 N/m2 throughout the cardiac cycle, and viscous dissipative stresses below 12 N/m2. The viscous dissipative stresses remain far below the threshold of red blood cell hemolysis, but could potentially damage platelets, implying the need for further study in the phenomenon of MHV hemolytic complications.
關鍵字 Hemolysis;Turbulent shear stress;Sub-grid scale;Turbulent dissipation;Dynamic equilibrium
語言 en
收錄於
會議性質 國際
校內研討會地點 無
研討會時間 20091218~20090530
通訊作者
國別 USA
公開徵稿 Y
出版型式 紙本
出處 Annals of Biomedical Engineering 38,　p.903-916
相關連結

機構典藏連結 ( http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/67979 )

機構典藏連結