چكيده به لاتين
Aortic aneurysm is a life-threatening disease due to the risk of aortic rupture. Aortic aneurysm is often associated with atherosclerosis and cardiovascular risk factors such as hypertension, dyslipidemia, genetics, smoking, age and gender. The formation of aortic aneurysm is related to the destruction of the aortic wall tissue, which leads to changes in the mechanical properties of the tissue, especially increasing the wall tension or reducing the final strength of the wall. Today, the decision for surgery is usually based on the diameter of the aneurysm. The purpose of this study is to design, model and simulate the ascending aortic aneurysm, using the results extracted from the Centam STM20 mechanical tensile test device in the mechanical properties laboratory, which was taken on the samples isolated from the aortic wall of a patient with ascending aortic aneurysm. . The samples were taken from patients who did not have a specific reason for having an aneurysm. Therefore, according to the extracted experimental results, the modulus of elasticity of ascending aortic aneurysm is considered equal to 2.11 MPa. The modulus of elasticity of the healthy ascending aorta is considered equal to 7.3 MPa by examining the biomechanical properties of the aorta through CT-angio images and the references and articles we had. Then, using the experimental results using the computational fluid dynamics numerical analysis method, a three-dimensional simulation of the ascending aorta and ascending aortic aneurysm was created in Ensys software as a fluid-solid interaction. After creating the interaction between fluid and solid in the software, the final results of von Mises resultant stress, resultant strain, shear stress, deformation, pressure and flow velocity in the ascending aorta and ascending aortic aneurysm, in two times of 0.25 seconds (maximum flow rate) and 0.8 seconds (end of cardiac cycle) has been investigated and compared. The results show that the resulting von Mises stress for aortic aneurysm at the time of maximum flow rate was equal to 11795 pascals, which is actually 2.37 times higher than the healthy aorta at the same time. It has also been observed that the deformation of the outcome for aortic aneurysm at the time of maximum flow rate is 4.47 times higher than that of healthy aorta at the same time. From the analysis of the flow velocity distribution results, it has been observed that the maximum flow velocity, in the aneurysm state, has decreased by 51.7% and 83.1% compared to the healthy state for the peak and end times of the heart rate cycle, respectively.