Airway Wall Stiffening Increases Peak Wall Shear Stress: A Fluid–Structure Interaction Study in Rigid and Compliant Airways

Abstract Background The effects of arterial wall compliance on blood flow have been revealed using fluid-structure interaction in last decades. However, microcirculation is not considered in previous researches. In fact, microcirculation plays a key role in regulating blood flow. Therefore, it is very necessary to involve microcirculation in arterial hemodynamics. Objective The main purpose of the present study is to investigate how wall compliance affects the flow characteristics and to establish the comparisons of these flow variables with rigid wall when microcirculation is considered. Methods We present numerical modeling in arterial hemodynamics incorporating fluid-structure interaction and microcirculation. A novel outlet boundary condition is employed to prescribe microcirculation in an idealised model. Results The novel finding in this work is that wall compliance under the consideration of microcirculation leads to the increase of wall shear stress in contrast to rigid wall, contrary to the traditional result that wall compliance makes wall shear stress decrease when a constant or time dependent pressure is specified at an outlet. Conclusions This work provides the valuable study of hemodynamics under physiological and realistic boundary conditions and proves that wall compliance may have a positive impact on wall shear stress based on this model. This methodology in this paper could be used in real model simulations.

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Numerical CFD / FSI Study of Teflon and Dacron for Use in the Femoral Artery Graft Procedure

Volume 7: Fluids Engineering ◽

10.1115/imece2019-10100 ◽

2019 ◽

Author(s):

Sukwinder Sandhu ◽

Kevin R. Anderson

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Femoral Artery ◽

Hoop Stress ◽

Fluid Structure Interaction ◽

Fluid Structure ◽

Structure Interaction ◽

Implant Materials ◽

Artery Graft ◽

Wall Shear

Abstract This paper presents Fluid Structure Interaction modeling of candidate implant materials used in the femoral artery graft medical procedure. Two candidate implant materials, namely Teflon and Dacron are considered and modeled using Computational Fluid Dynamics (CFD) and structural Finite Element Analysis (FEA) to obtain Fluid Structure Interaction (FSI) developed stresses within the candidate materials as a result of non-Newtonian blood flowing in a pulsatile unsteady fashion into the femoral artery implant tube. The pertinent findings for a pulsatile velocity maximum magnitude of 0.3 m/s and period of oscillation of 2.75 sec are as follows. For the biological tissue the wall shear stress is found to be 2.15 × 104 Pa, the hoop stress is found to be 1.6 × 104 Pa. For the Teflon implant material, the wall shear stress is found to be 1.177 × 104 Pa, the hoop stress is found to be 2.2 × 104 Pa. For the Dacron implant material the wall shear stress is found to by 3.9 × 104 Pa, the hoop stress is found to be 2.17 × 104 Pa. Based upon the analysis herein the PTFE material would be recommended.

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Discordance of the Areas of Peak Wall Shear Stress and Tissue Stress in Coronary Artery Plaques as Revealed by Fluid-Structure Interaction Finite Element Analysis

International Heart Journal ◽

10.1536/ihj.54.54 ◽

2013 ◽

Vol 54 (1) ◽

pp. 54-58 ◽

Cited By ~ 9

Author(s):

Tatsuya Asanuma ◽

Yasutomi Higashikuni ◽

Hiroshi Yamashita ◽

Ryozo Nagai ◽

Toshiaki Hisada ◽

...

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Shear Stress ◽

Coronary Artery ◽

Wall Shear Stress ◽

Fluid Structure Interaction ◽

Element Analysis ◽

Fluid Structure ◽

Structure Interaction ◽

Wall Shear

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Wall Shear Stress in an MRI-Based Subject-Specific Human Aorta Using Fluid-Structure Interaction

ASME 2010 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2010-19346 ◽

2010 ◽

Author(s):

Jonas Lantz ◽

Johan Renner ◽

Matts Karlsson

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Thrombus Formation ◽

Fluid Structure Interaction ◽

Human Aorta ◽

Shear Stresses ◽

Fluid Structure ◽

Structure Interaction ◽

Increased Risk ◽

Wall Shear

Wall shear stress (WSS) is well established as an indicator of increased risk for development of atherosclerotic plaques, platelet activation and thrombus formation [1]. Prediction and simulation of the sites of wall shear stresses that are deemed dangerous before intervention would be of great aid to the surgeon. However, the geometries used for these types of simulations are often approximated to be rigid. To more accurately capture the flow and arterial wall response of a realistic human aorta, fluid-structure interaction (FSI) which allows movement of the wall, is needed. Hence, the pressure wave and its effect on the wall motion are resolved and enables a more physiological model as compared to a rigid wall case.

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MODELING OF SUPERIOR MESENTERIC ARTERY ANEURYSM USING FLUID–STRUCTURE INTERACTION

Journal of Mechanics in Medicine and Biology ◽

10.1142/s0219519415500050 ◽

2015 ◽

Vol 15 (01) ◽

pp. 1550005

Author(s):

BAHARAK EBRAHIMI ◽

KAMRAN HASSANI

Keyword(s):

Shear Stress ◽

Shear Rate ◽

Wall Shear Stress ◽

Superior Mesenteric Artery ◽

Mesenteric Artery ◽

Cardiac Cycle ◽

Fluid Structure Interaction ◽

Fluid Structure ◽

Structure Interaction ◽

Wall Shear

The aim of this study was to model the blood flow and predict related hemodynamics characteristics in healthy superior mesenteric artery (SMA) and saccular aneurysm cases. A fluid–structure interaction (FSI) method was performed, using an arbitrary Langrangian–Eulerian mesh. The computational mesh was generated using anatomical data from available human computed tomography (CT)-images. Combining constitution and momentum equations, projection method, the discretized resultant equation were numerically solved for velocity, pressure, shear stress and vortices for healthy/aneurysmal artery. The results including velocity contours, pressure contours, shear rate values, and vortices were obtained and analyzed for three main steps including peak systole, diastole, and end of cardiac cycle. Profiles show the varying velocity and pressure for a pulsatile flow input before and after aneurysms. They also show the formation of single or multiple vortices at aneurysmal area and decrease of wall shear stress with aneurysm enlargement. Furthermore, shear rate values at the neck of aneurysms exceed throughout the entire cardiac cycle. The outcome of the computational analysis is then compared to information available on pressure, vortices and wall shear stress from some clinical findings.

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Fluid–structure interaction analysis of hemodynamics in different degrees of stenoses considering microcirculation function

Advances in Mechanical Engineering ◽

10.1177/1687814021989012 ◽

2021 ◽

Vol 13 (1) ◽

pp. 168781402198901

Author(s):

Fan He ◽

Lu Hua ◽

Tingting Guo

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Arterial Wall ◽

Interaction Analysis ◽

Fluid Structure Interaction ◽

Developed Countries ◽

Fluid Structure ◽

Structure Interaction ◽

Simulation Based ◽

Wall Shear

In developed countries, stenosis is the main cause of death. To investigate hemodynamics within different degrees of stenoses, a stenosis model incorporating fluid–structure interaction and microcirculation function is used in this paper. Microcirculation is treated as a seepage outlet boundary condition. Compliant arterial wall is considered. Numerical simulation based on fluid–structure interaction is performed using finite element method. Our results indicate that (i) the increasing degree of stenosis makes the pressure drop increase, and (ii) the wall shear stress and the velocity in the artery zone may be more sensitive than the pressure with the increase of percentage stenosis, and (iii) there are higher wall shear stress and flow velocity in the post-stenosis region of severer stenosis. This work contributes to understand hemodynamics for different degrees of stenoses and it provides detailed information for stenosis and microcirculation function.

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Investigation of two-way fluid-structure interaction of blood flow in a patient-specific left coronary artery

Bio-Medical Materials and Engineering ◽

10.3233/bme-201171 ◽

2021 ◽

pp. 1-18

Author(s):

Abdulgaphur Athani ◽

N.N.N. Ghazali ◽

Irfan Anjum Badruddin ◽

Sarfaraz Kamangar ◽

Ali E. Anqi ◽

...

Keyword(s):

Blood Flow ◽

Shear Stress ◽

Coronary Artery ◽

Wall Shear Stress ◽

Left Coronary Artery ◽

Fluid Structure Interaction ◽

Patient Specific ◽

Hemodynamic Parameters ◽

Fluid Structure ◽

Structure Interaction

BACKGROUND: The blood flow in the human artery has been a subject of sincere interest due to its prime importance linked with human health. The hemodynamic study has revealed an essential aspect of blood flow that eventually proved to be paramount to make a correct decision to treat patients suffering from cardiac disease. OBJECTIVE: The current study aims to elucidate the two-way fluid-structure interaction (FSI) analysis of the blood flow and the effect of stenosis on hemodynamic parameters. METHODS: A patient-specific 3D model of the left coronary artery was constructed based on computed tomography (CT) images. The blood is assumed to be incompressible, homogenous, and behaves as Non-Newtonian, while the artery is considered as a nonlinear elastic, anisotropic, and incompressible material. Pulsatile flow conditions were applied at the boundary. Two-way coupled FSI modeling approach was used between fluid and solid domain. The hemodynamic parameters such as the pressure, velocity streamline, and wall shear stress were analyzed in the fluid domain and the solid domain deformation. RESULTS: The simulated results reveal that pressure drop exists in the vicinity of stenosis and a recirculation region after the stenosis. It was noted that stenosis leads to high wall stress. The results also demonstrate an overestimation of wall shear stress and velocity in the rigid wall CFD model compared to the FSI model.

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Hemodynamic Abnormalities in Stented Carotid Artery: A Fluid Structure Interaction Study

Volume 7: Fluids and Heat Transfer, Parts A, B, C, and D ◽

10.1115/imece2012-93091 ◽

2012 ◽

Author(s):

Thomas A. Metzger ◽

Santanu Chandra ◽

Philippe Sucosky

Keyword(s):

Shear Stress ◽

Carotid Artery ◽

Wall Shear Stress ◽

Stent Implantation ◽

Arterial Wall ◽

Fluid Structure Interaction ◽

Normal Model ◽

Stent Angioplasty ◽

Structure Interaction ◽

Wall Shear

Balloon-stented angioplasty is a common treatment for carotid arterial atherosclerosis. Clinical studies have shown that within 6 months of the initial procedure, 25% of stented-angioplasty patients develop restenosis, a postoperative narrowing of the artery due to plaque accumulation onto the stent. While hemodynamics and more specifically low oscillatory wall-shear stress have been identified as key factors promoting atherogenesis, their role in restenosis following stent implantation remains unclear. We hypothesize that the implantation of a stent generates hemodynamic abnormalities consisting of low wall shear stresses in the vicinity of arterial wall regions prone to restenosis. The objective of this study was to compare computationally the hemodynamics in normal (healthy), stenosed (atherosclerotic) and stented carotid artery bifurcation models and to investigate potential correlations between regions presenting high hemodynamic abnormalities and regions prone to postoperative stent angioplasty restenosis. Realistic, three-dimensional models of normal, stenosed and stented human carotid bifurcations consisting of the common (CCA), external (ECA) and internal (ICA) carotid arteries were developed using the computer-assisted design software Solid Edge. The characteristic dimensions of the normal and stenosed models were obtained from previously published human data. The stented model was designed by modeling the inner surface of the ICA bulb region as a rigid cylindrical surface mimicking the presence of a stent. Fluid-structure interaction (FSI) simulations were carried out using the adaptive arbitrary Lagrangian Eulerian (ALE) approach of ANSYS 14 to simulate flow and arterial wall dynamics in each model subjected to physiologic pressure and flow rate. As expected, the atherosclerotic model resulted in higher velocity and wall shear stress (WSS) levels than the normal model due to the reduced ICA lumen. In addition, while stent implantation restored the hemodynamic performance of the vessel, it generated lower WSS than in the normal model, which may contribute to restenosis. This study provides new insights into the possible hemodynamic roots of postoperative stent angioplasty restenosis.

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