Shear stress rosettes capture the complex flow physics in diseased arteries

JOURNAL OF BIOMECHANICS

卷:104

Article

Krishna, C. Vamsi^1,6  Suja, Vineeth Chandran²  Watton, Paul N.^3,4,5  Arakeri, Jaywant H.¹  Gundiah, Namrata¹ 

[1] Indian Inst Sci, Dept Mech Engn, Bangalore 560012, Karnataka, India

[2] Stanford Univ, Dept Chem Engn, Stanford, CA 94305 USA

[3] Univ Sheffield, Dept Comp Sci, Sheffield, S Yorkshire, England

[4] Univ Sheffield, INSIGNEO Inst Silico Med, Sheffield, S Yorkshire, England

[5] Univ Pittsburgh, Dept Mech Engn & Mat Sci, Pittsburgh, PA USA

[6] Univ Southern Calif, Dept Aerosp & Mech Engn, Los Angeles, CA 90089 USA

关键词: Arterial flows;    Secondary flows and bidirectionality;    Shear metrics;    Aneurysms;   

DOI  :  10.1016/j.jbiomech.2020.109721

来源: Elsevier

【 摘 要 】

Wall shear stress (WSS) is an important parameter in arterial mechanobiology. Various flow metrics, such as time averaged WSS (TAWSS), oscillatory shear index (OSI), and transWSS, have been used to characterize and relate possible WSS variations in arterial diseases like aneurysms and atherosclerosis. We use a graphical representation of WSS using shear rosettes to map temporal changes in the flow dynamics during a cardiac cycle at any spatial location on the vessel surface. The presence of secondary flows and flow reversals can be interpreted directly from the shape of the shear rosette. The mean WSS is given by the rosette centroid, the OSI by the splay around the rosette origin, and the transWSS by its width. We define a new metric, anisotropy ratio (AR), based on the ratio of the length to width of the shear rosette, to capture flow bi-directionality. We characterized the flow physics in controls and patient specific geometries of the ascending aorta (AA) and internal carotid artery (ICA) that have fundamentally different flow dynamics due to differences in the Reynolds and Womersley numbers. The differences in the flow dynamics are well reflected in the shapes of the WSS rosettes and the corresponding flow metrics. (C) 2020 Elsevier Ltd. All rights reserved.

【 授权许可】

Free