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بررسی اثر بارهای مکانیکی محیطی روی آنوریسم مغزی
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بررسی اثر بارهای مکانیکی محیطی روی آنوریسم مغزی

عبداللهی، رحیم Abdollahi, Rahim

Effects of Mechanical Loading Environment on Aneurysm

Abdollahi, Rahim | 2014

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  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 45826 (45)
  4. University: Sharif University of Technology
  5. Department: Aerospace Engineering
  6. Advisor(s): Abedian, Ali
  7. Abstract:
  8. Human body is subjected to body accelerations or vibrations in several circumstances. During gravitational changes, the hydrostatic pressure gradient along the body axis changes, and then body fluids are redistributed. Prolonged exposure to high level external acceleration may lead to serious or even fatal situations on account of disturbances in blood flow. Due to physiological importance of body acceleration many theoretical investigations have been carried out for the flow of blood under the influence of body acceleration. In this study, the mechanical loads that pilots experience during flight are considered. The aim of the present study is to investigate the effects of mechanical loading environment on cerebral aneurysm. Intracranial Cerebral Aneurysm (ICA) is the localized dilation of cerebral arteries due to a degenerative arterial disease causing a local wall weakness. They usually occur on or near the circle of Willis. Sudden rupture of cerebral aneurysms is the leading cause of subarachnoid hemorrhage which is a serious disease associated with high mortality and morbidity. In this research work, we have developed a finite-element fluid-structure interaction (FSI) which enjoys 2-way coupling model to apply to an idealized Middle Cerebral Aneurysm (MCA).The blood flow was characterized as a steady, laminar and Newtonian flow velocity at the inflow and a blood pressure at the outflow. While the arteries walls consist of three layers, the contribution of inner layer is negligible in mechanical load-bearing. The arterial wall was modeled as a two layer wall named as media and adventia with different incompressible isotropic hyperelastic Mooney-Rivlin (M-R) material for each layer in aneurysmic region. The results show that ICAs are subjected to higher hemodynamic stresses and are more prone to rupture in presence of mechanical loading. The effects of acceleration on the wall shear stress, static pressure, von-Mises stress, deformation of cerebral aneurysm, and also the interactions between two layers are investigated
  9. Keywords:
  10. Fluid-Structure Interaction ; Mechanical Loading ; Willis Circle ; Cerebral Eneurysm

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