• Title/Summary/Keyword: Elastic and rigid wall vessel

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Effects of Elastic Blood Vessel Motions on the Wall Shear Stresses for Pulsatile Flow of a Newtonian Fluid and Blood (뉴턴유체와 혈액의 맥동유동시 탄성혈관의 운동이 벽면전단응력분포에 미치는 영향)

  • Roh, Hyung-Woon;Kim, Jae-Soo;Park, Gil-Moon;Suh, Sang-Ho
    • Proceedings of the KSME Conference
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    • 2001.11b
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    • pp.318-323
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    • 2001
  • Characteristics of the pulsatile flow in a 3-dimensional elastic blood vessel are investigated to understand the blood flow phenomena in the human body arteries. In this study, a model for the elastic blood vessel is proposed. The finite volume prediction is used to analyse the pulsatile flow in the elastic blood vessel. Variations of the pressure, velocity and wall shear stress of the pulsatile flow in the elastic blood vessel are obtained. The magnitudes of the velocity waveforms in the elastic blood vessel model are larger than those in the rigid blood vessel model. The wall shear stresses on the elastic vessel vary with the blood vessel motions. Amplitude indices of the wall shear stress for blood in the elastic blood vessel are $4\sim5$ times larger than those of the Newtonian fluid. As the phase angle increased, point of the phase angle is are moved forward and the wall shear stresses are increased for blood and the Newtonian fluid.

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The Effects of Wall Elasticity on Wall Shear Rate of a Divergent Tube (Vascular Graft) (벽 탄성도가 확장관(인조혈관) 벽 전단변형률에 미치는 영향)

  • Rhee, Kye-Han;Lee, Sang-Man
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.23 no.6 s.165
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    • pp.912-921
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    • 1999
  • Shear stress acting on the arterial wall by blood flow is an important hemodynamic factor influencing blocking of blood vessel by thickening of an arterial wall. In order to study the effects of wall elasticity on the wall shear rate distribution in an artery-divergent graft anastomosis, a rigid and a elastic model are manufactured. These models are placed in a pulsatile flow loop, which can generate the desired flow waveform. Flow visualization method using a photochromic dye is used to measure the wall shear rate distribution. The accuracy of measuring technique is verified by comparing the measured wall shear rate in the straight portion of a model with the theoretical solution. Measured wall shear rates depend on the wall elasticity and flow waveform. The mean and maximum shear rate in the elastic model are lower than those in rigid model, and the decreases are more significant near the end of a divergent tube. The reduction of mean and maximum of wall shear rate in an elastic model are up to 17 percent.

Modeling of Hemodynamics in Stenosed Artery (협착 동맥혈관의 혈류유동 모델링)

  • Kim, Seong-Jong;Park, Young-Ran;Kim, Shagn-Jin;Kang, Hyung-Sub;Kim, Jin-Shang;Oh, Sung-Hoon;Kang, Sung-Jun;Kim, Gi-Beum
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.5
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    • pp.2285-2290
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    • 2012
  • This study is about atherosclerosis which occupies the highest rate in many diseases people have and we have studied about atherosclerosis for abdominal aorta. Atherosclerosis is the phenomenon which blood vessel gets narrower, harder and thicker due to the stenosis of colesterol in blood vessel. If it becomes worse, arteries will be hard and blood can't flow smoothly, and even it can reach to death. In this study, the geometric models of the considered stenotic blood flow are two different types of constriction of cross-sectional area of blood vessel; 20 and 45% of constriction in each elastic wall and rigid wall. We have modeled by using finite element method to observe the changes of velocity and pressure. In case of the diameter of blood vessel decreased 45% in elastic wall model, the values of velocity and pressure were higher than the case of 20% and in case of the diameter of blood vessel decreased 45% in rigid wall model, the values of velocity and pressure were higher than the case of 20%. In cases of elastic wall models of the diameters of blood vessels decreased each of 20% and 45%, recirculation zones appeared. This results show understanding of hemodynamic properties depending on stenosed blood vessels.