Relation between Wall Shear Stress and Aneurysm of Initiation in Pulsating Flow

The distributions of mass transfer rate and wall shear stress in sinusoidal laminar pulsating flow through a two-dimensional asymmetric stenosed channel have been studied experimentally and numerically. The distributions are measured by the electrochemical method. The measurement is conducted at a Reynolds number of about 150, a Schmidt number of about 1000, a nondimensional pulsating frequency of 3.40, and a nondimensional flow amplitude of 0.3. It is suggested that the deterioration of an arterial wall distal to stenosis may be greatly enhanced by fluid dynamic effects.

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Pulsating Flow through a Pipe Orifice : 2nd Report, Flow Patterns and Wall Shear Stress

Bulletin of JSME ◽

10.1299/jsme1958.26.1330 ◽

1983 ◽

Vol 26 (218) ◽

pp. 1330-1339

Author(s):

Takayoshi MUTO ◽

Mitsuyuki MIZUNO

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Flow Patterns ◽

Pulsating Flow ◽

Flow Through ◽

Wall Shear

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Wall Shear Stress and Gradient at Anterior Communicating Artery in Pulsating Flow

10.1115/imece2000-2615 ◽

2000 ◽

Author(s):

Ryuhei Yamaguchi ◽

Susumu Kudo ◽

Hiroyuki Yamanobe ◽

Mikio Nakajima ◽

Hiroshi Ujiie

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Cerebral Artery ◽

Major Part ◽

Cerebral Arteries ◽

Circle Of Willis ◽

Pulsating Flow ◽

Anterior Communicating Artery ◽

Wall Shear

Abstract The aneurysm in the cerebral artery is apt to initiate around the “Circle of Willis”. The anterior communicating artery (ACoA), which composes one of major part of the circle of Willis, is the most predilection artery of the aneurysm. This artery is characterized by a singular geometry. At this artery, two proximal anterior cerebral arteries (A1, confluence) join facing each other. Just at this artery, the flow bifurcates two distal anterior cerebral arteries (A2, bifurcation). Namely, this artery has a function as a bypass channel. Therefore, the flow around the anterior communicating artery would be very unstable. The aneurysm arises around the apex of this artery where the confluent flow collides.

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Sinusoidal Variation of Wall Shear Stress in Daughter Tube Through 45 Deg Branch Model in Laminar Flow

Journal of Biomechanical Engineering ◽

10.1115/1.2895695 ◽

1994 ◽

Vol 116 (1) ◽

pp. 119-126 ◽

Cited By ~ 21

Author(s):

Ryuhei Yamaguchi ◽

Kenji Kohtoh

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Steady Flow ◽

Electrochemical Method ◽

Sine Wave ◽

Pulsating Flow ◽

Branch Model ◽

Flow Situation ◽

Wall Shear ◽

Parent Tube

The present paper describes the experimental implemented work on the flow situation through a branch model having a daughter tube bifurcated from a parent tube at 45 deg. Experiments have been conducted utilizing an electrochemical method. The results show that, even in steady flow, the wall shear stress along the proximal wall in the daughter tube varies significantly with position in the form of a damped sine wave. For pulsating flow at the nondimensional pulsating frequency of α = 6.6, the above mentioned tendency appears to be severe, and the distribution of its amplitude in pulsating flow is similar to that of wall shear stress in steady flow.

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Wall Shear Stress and Initiation of Aneurysm around Anterior Communicating Artery in Pulsating Flow.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B ◽

10.1299/kikaib.66.652_3124 ◽

2000 ◽

Vol 66 (652) ◽

pp. 3124-3130

Author(s):

Ryuhei YAMAGUCHI ◽

Susumu KUDO ◽

Hiroyuki YAMANOBE ◽

Mikio NAKASHIMA ◽

Ryota SUGIHARA ◽

...

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Pulsating Flow ◽

Anterior Communicating Artery ◽

Wall Shear

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0222 Wall shear stress and secondary flow of Renal Arterial Branch during Pulsating Flow

The Proceedings of the Bioengineering Conference Annual Meeting of BED/JSME ◽

10.1299/jsmebio.2009.22.206 ◽

2010 ◽

Vol 2009.22 (0) ◽

pp. 206

Author(s):

Masatoshi YANASHITA ◽

Fuyou LIANG ◽

Hao LIU ◽

Ryuhei YAMAGUCHI

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Secondary Flow ◽

Pulsating Flow ◽

Wall Shear ◽

Arterial Branch

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Study on the disturbance effect of pulsating flow and heat transfer in self-excited oscillation shear layer

Thermal Science ◽

10.2298/tsci210611347h ◽

2021 ◽

pp. 347-347

Author(s):

Gaoquan Hu ◽

Zhaohui Wang ◽

Yiwei Fan ◽

Hongmei Yuan ◽

Quanjie Gao

Keyword(s):

Heat Transfer ◽

Boundary Layer ◽

Shear Stress ◽

Wall Shear Stress ◽

Layer Thickness ◽

Boundary Layer Thickness ◽

Pulsating Flow ◽

Transfer Efficiency ◽

Heat Transfer Efficiency ◽

Wall Shear

The fluid movement motion has an important influence on the evolution of the pulsating flow in the hot runner. Using the Large Eddy Simulation numerical method, the instantaneous velocity, wall shear stress, boundary layer thickness and Nu number of hot runner section under different structural parameters at an inlet pressure of 5000 Pa were studied. The research results showed that the backflow vortex can be formed in the hot runner, and the fluid at the axis center of hot runner can form a pulsating flow under the squeezing action of the backflow vortex. The pulsating flow had a strong disturbance effect on the fluid around the axis center and accelerated the heat exchange between the fluid around the axis center and the wall. The disturbance effect of pulsating flow gradually strengthened with the flow of the main flow to the downstream. When d2/d1 was 1-1.8, the wall shear stress first increased and then decreased, and the wall heat transfer efficiency first increased and then decreased. The maximum wall shear stress was 36.4Pa. When L/D was 0.45-0.65, the boundary layer thickness first decreased and then increased, and the heat transfer efficiency first increased and then decreased. The minimum boundary layer thickness was 0.392mm and the maximum Nu number was 138. When d2/d1=1.4 and L/D=0.55, the maximum comprehensive evaluation factor reached 1.241, and the heat transfer efficiency was increased by 24.1%.

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