Analysis of Unsteady Blood Flow in the Human Aortic Bifurcation
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摘要: 运用流体力学中的三维非定常Navier-Stokes方程作为血液流动的控制方程,并采用计算流体力学方法对人体主动脉弓及分支血管内非Newton(牛顿)血液黏度模型下血流进行瞬态数值模拟.分析了一个心动周期内不同时刻血流动力学特征参数的分布对动脉粥样硬化斑块形成的影响,并与Newton血液黏度模型下的血管壁面压力和壁面切应力特征参数进行对比.结果表明:与Newton血液模型相比,非Newton血液模型下血流分布更符合真实血流特性;在心动收缩期,分支血管外侧壁附近存在面积较大的低速涡流区,该区域内血管壁面压力与壁面切应力具有较大的变化量,血液中的血小板、脂质和纤维蛋白等易沉积,血管内壁易疲劳损伤并发生血管重构,促使动脉粥样硬化斑块形成;而在心动舒张期,分支血管内血流速度分布均匀,血管壁面压力与壁面切应力变化量较小,血管壁受到较小的应力作用,对动脉粥样硬化斑块形成的作用较小.Abstract: Based on the 3D unsteady Navier-Stokes equations as the governing equations, the blood flow in the human aortic bifurcation was simulated by means of the non-Newtonian blood model with the computational fluid dynamics method. The influence of blood flow characteristic parameter distributions on the formation of atherosclerotic plaques at the feature points within a cardiac cycle was investigated, and a comparison of the wall pressure and wall shear stress parameters was made between the Newtonian blood model and the non-Newtonian blood model. The results show that, compared to the Newtonian blood model, the non-Newtonian blood model is more suitable for the description of real blood flow characteristics. Larger blood stagnation areas, more complex wall pressure and wall shear stress distributions exist around the lateral walls of the bifurcation blood vessels during the systolic cycle, more probably causing deposition of fat particles, platelets and fibrin in the blood vessels which are liable to wall injury and reconstruction, in turn formation of atherosclerotic plaques. However, smaller blood stagnation areas, less changes of wall pressure and wall shear stress distributions happen around the lateral walls of the bifurcation blood vessels during the diastolic cycle, with less influence on the formation of atherosclerotic plaques.
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Key words:
- cardiac cycle /
- aortic bifurcation /
- non-Newtonian blood /
- atherosclerotic plaque
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[1] SUN Zhong-hua, XU Lei. Computational fluid dynamics in coronary artery disease[J].Computerized Medical Imaging and Graphics,2014,38(8): 651-663. [2] 梅克赫默·Kh·S, 哈劳恩·M·H, 艾可特·M·A. 磁场、多孔性和各向异性动脉壁有多处狭窄段时对血液流动的影响[J]. 应用数学和力学, 2011,32(8): 981-997.(Mekheimer Kh S, Haroun M H, El Kot M A. Effects of magnetic field, porosity and wall properties for anisotropically elastic multi-stenosis arteries on the characteristics of blood flow[J].Applied Mathematics and Mechanics,2011,32(8): 981-997.(in Chinese)) [3] Piskin S, Serdar Celebi M. Analysis of the effects of different pulsatile inlet profiles on the hemodynamical properties of blood flow in patient specific carotid artery with stenosis[J].Computers in Biology and Medicine,2013,43(6): 717-728. [4] 梅立泉, 赵柯. 分叉血管中动脉狭窄对血液流动的影响[J]. 应用力学学报, 2013,30(3): 417-421.(MEI Li-quan, ZHAO Ke. The influence of arterial stenosis in bifurcate blood vessel on the blood flow[J].Chinese Journal of Applied Mechanics,2013,30(3): 417-421.(in Chinese)) [5] 王晓曦. 冠状动脉局部血流动力学分析及对斑块影响的可行性研究[D]. 硕士学位论文. 北京: 中国人民解放军总医院, 2013.(WANG Xiao-xi. Feasibility of hemodynamic analysis of local coronary arteries and effects on plaques[D]. Master Thesis. Beijing: General Hospital of PLA, 2013.(in Chinese)) [6] Wellnhofer E, Osman J, Kertzscher U, Affeld K, Fleck E, Goubergrits L. Flow simulation studies in coronary arteries-impact of side-branches[J].Atherosclerosis,2010,213(2): 475-481. [7] 刘赵淼, 马瑞艳, 叶红玲, 张谭. 弯曲动脉血管中血液流动对血栓形成的影响[J]. 科技导报, 2009,27(1): 50-55.(LIU Zhao-miao, MA Rui-yan, YE Hong-ling, ZHANG Tan. Influences on thrombosis of blood flow in curves blood vessel[J].Science and Technology Review,2009,27(1): 50-55.(in Chinese)) [8] Vimmr J, Jonasova A, Bublik O. Numerical analysis of non-Newtonian blood flow and wall shear stress in realistic single, double and triple aorto-coronary bypasses[J].International Journal for Numerical Methods in Biomedical Engineering,2013,29(10): 1057-1081. [9] Jozwik K, Obidowski D. Numerical simulations of the blood flow through vertebral arteries[J].Journal of Biomechanics,2010,43(2): 177-185. [10] Johnston B M, Johnston P R. Simulations of pulsatile blood flow in tapered S-shaped in-plane and out-of-plane coronary arteries[C]//18th World IMACS/MODSIM Congress,Cairns, Australia, 2009: 13-17. [11] Matos H M, Oliveira P J. Steady and unsteady non-Newtonian inelastic flows in a planar T-junction[J].International Journal of Heat and Fluid Flow,2013,39(1): 102-126. [12] Chaichana T, Sun Z, Jewkes J. Computation of hemodynamics in the left coronary artery with variable angulations[J].J Biomech,2011,44(10): 1869-1878. [13] 摩塔扎维尼亚·Z, 扎尔·A, 麦迪查德·A. 肾动脉变窄和流-固结构相互作用对非Newton 脉动流的影响——一个真实的腹部主动脉和肾动脉模型[J]. 应用数学和力学, 2012,33(2): 164-176.(Mortazavinia Z, Zare A, Mehdizadeh A. Effects of renal artery stenosis in a realistic model of abdominal aorta and renal arteries incorporating FSI and pulsatile non-Newtonian blood flow[J].Applied Mathematics and Mechanics,2012,33(2): 164-176.(in Chiense)) [14] Chatzizisis Y S, Coskun A U, Jonas M, Edelman E R, Feldman C L, Stone P H. Role of endothelial shear stress in the natural history of coronary atherosclerosis and vascular remodeling molecular, cellular, and vascular behavior[J].Journal of the American College of Cardiology,2007,49(25): 2379-2393. [15] 姬新颖, 李涛, 刘瑞敏, 白慧玲, 牛保华, 娄强, 马远方. 血流动力学新特点与冠状动脉粥样硬化发生的关系[J]. 河南大学学报(医学版), 2011,30(4): 231-238.(JI Xin-ying, LI Tao, LIU Rui-min, BAI Hui-ling, NIU Bao-hua, LOU Qiang, MA Yuan-fang. Relationship between a newly described hemodynamical feature with the pathogenesis of atherosclerosis in coronary arteries[J].Journal of Henan University (Medical Science),2011,30(4): 231-238.(in Chinese)) [16] Martin D, Zaman A, Hacker J, Mendelow D, Birchall D. Analysis of hemodynamic factors involved in carotid atherosclerosis using computational fluid dynamics[J].The British Journal of Radiology,2009,8(2): 33-38.
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