The effect of hemodynamics on cardiovascular disease (CVD) is very important since CVD is the number one killer nationwide and around the globe. Coronary artery disease (CAD), also called arteriosclerosis, is a common disease found in human arteries, including coronary arteries and the common carotid artery. The abdominal aorta is also affected by atherosclerotic aneurysm. Formation of atherosclerosis obstructs the blood flow in arteries and changes the hemodynamics pattern. Numerical and experimental modeling in a tapered artery using turbulent models has been untouched so far. To investigate the cause of atherosclerosis and atherosclerotic aneurysm, simulations were done using the finite volume method via FLUENT 6.3.26. Wilcox’s two-equation standard κ-ω model was used for numerical simulation of a tapered artery and abdominal aortic aneurysm. The tapered artery had a diameter reduction of 25 percent at the stenosed area. The two-equation turbulence κ-ω model was employed on a geometry to validate the numerical results with velocity profiles of experimental results. Blood was assumed to be Newtonian in all simulations. The main objectives of this thesis were as follows:

1. To study the shear stress and blood streamlines of tapered artery at different Reynolds number using the κ-ω model.
2. To simulate the pulsatile flow conditions on a tapered artery and abdominal aortic aneurysm.
3. To predict and validate the kick-start of atherosclerosis based on hemodynamic conditions.
4. To study the effect of turbulent viscosity on shear stress.