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Tamie L Poepping - One of the best experts on this subject based on the ideXlab platform.
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Transitional flow analysis in the Carotid Artery Bifurcation by proper orthogonal decomposition and particle image velocimetry
Medical Engineering & Physics, 2013Co-Authors: Sarah Kefayati, Tamie L PoeppingAbstract:Abstract Blood flow instabilities in the Carotid Artery Bifurcation have been highly correlated to clot formation and mobilization resulting in ischemic stroke. In this work, PIV-measured flow velocities in normal and stenosed Carotid Artery Bifurcation models were analyzed by means of proper orthogonal decomposition (POD). Through POD analysis, transition to more complex flow was visualized and quantified for increasing stenosis severity. While no evidence of transitional flow was seen in the normal model, the 50%-stenosed model started to show characteristics of transitional flow, which became highly evident in the 70% model, with greatest manifestation during the systolic phase of the cardiac cycle. By means of a model comparison, we demonstrate two quantitative measures of the flow complexity through the power-law decay slope of the energy spectrum and the global entropy. The more complex flow in the 70%-stenosed model showed a flatter slope of energy decay (−0.91 compared to −1.34 for 50% stenosis) and higher entropy values (0.26 compared to 0.17). Finally, the minimum temporal resolution required for POD analysis of Carotid Artery flow was found to be 100 Hz when determined through a more typical energy-mode convergence test, as compared to 400 Hz based on global entropy values.
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3-D flow characterization and shear stress in a stenosed Carotid Artery Bifurcation model using stereoscopic PIV technique
2010 Annual International Conference of the IEEE Engineering in Medicine and Biology, 2010Co-Authors: Sarah Kefayati, Tamie L PoeppingAbstract:The Carotid Artery Bifurcation is a common site of atherosclerosis which is a major leading cause of ischemic stroke. The impact of stenosis in the atherosclerotic Carotid Artery is to disturb the flow pattern and produce regions with high shear rate, turbulence, and recirculation, which are key hemodynamic factors associated with plaque rupture, clot formation, and embolism. In order to characterize the disturbed flow in the stenosed Carotid Artery, stereoscopic PIV measurements were performed in a transparent model with 50% stenosis under pulsatile flow conditions. Simulated ECG gating of the flowrate waveform provides external triggering required for volumetric reconstruction of the complex flow patterns. Based on the three-component velocity data in the lumen region, volumetric shear-stress patterns were derived.
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numerical analysis of the hemodynamic effect of plaque ulceration in the stenotic Carotid Artery Bifurcation
Proceedings of SPIE, 2009Co-Authors: Tamie L Poepping, Emily Y Wong, Jaques S Milner, David A Steinman, David W HoldsworthAbstract:The presence of ulceration in Carotid Artery plaque is an independent risk factor for thromboembolic stroke. However, the associated pathophysiological mechanisms - in particular the mechanisms related to the local hemodynamics in the Carotid Artery Bifurcation - are not well understood. We investigated the effect of Carotid plaque ulceration on the local time-varying three-dimensional flow field using computational fluid dynamics (CFD) models of a stenosed Carotid Bifurcation geometry, with and without the presence of ulceration. CFD analysis of each model was performed with a spatial finite element discretization of over 150,000 quadratic tetrahedral elements and a temporal discretization of 4800 timesteps per cardiac cycle, to adequately resolve the flow field and pulsatile flow, respectively. Pulsatile flow simulations were iterated for five cardiac cycles to allow for cycle-to-cycle analysis following the damping of initial transients in the solution. Comparison between models revealed differences in flow patterns induced by flow exiting from the region of the ulcer cavity, in particular, to the shape, orientation and helicity of the high velocity jet through the stenosis. The stenotic jet in both models exhibited oscillatory motion, but produced higher levels of phase-ensembled turbulence intensity in the ulcerated model. In addition, enhanced out-of-plane recirculation and helical flow was observed in the ulcerated model. These preliminary results suggest that local fluid behaviour may contribute to the thrombogenic risk associated with plaque ulcerations in the stenotic Carotid Artery Bifurcation.
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Medical Imaging: Image-Guided Procedures - Numerical analysis of the hemodynamic effect of plaque ulceration in the stenotic Carotid Artery Bifurcation
Medical Imaging 2009: Visualization Image-Guided Procedures and Modeling, 2009Co-Authors: Emily Y Wong, Tamie L Poepping, Jaques S Milner, David A Steinman, David W HoldsworthAbstract:The presence of ulceration in Carotid Artery plaque is an independent risk factor for thromboembolic stroke. However, the associated pathophysiological mechanisms - in particular the mechanisms related to the local hemodynamics in the Carotid Artery Bifurcation - are not well understood. We investigated the effect of Carotid plaque ulceration on the local time-varying three-dimensional flow field using computational fluid dynamics (CFD) models of a stenosed Carotid Bifurcation geometry, with and without the presence of ulceration. CFD analysis of each model was performed with a spatial finite element discretization of over 150,000 quadratic tetrahedral elements and a temporal discretization of 4800 timesteps per cardiac cycle, to adequately resolve the flow field and pulsatile flow, respectively. Pulsatile flow simulations were iterated for five cardiac cycles to allow for cycle-to-cycle analysis following the damping of initial transients in the solution. Comparison between models revealed differences in flow patterns induced by flow exiting from the region of the ulcer cavity, in particular, to the shape, orientation and helicity of the high velocity jet through the stenosis. The stenotic jet in both models exhibited oscillatory motion, but produced higher levels of phase-ensembled turbulence intensity in the ulcerated model. In addition, enhanced out-of-plane recirculation and helical flow was observed in the ulcerated model. These preliminary results suggest that local fluid behaviour may contribute to the thrombogenic risk associated with plaque ulcerations in the stenotic Carotid Artery Bifurcation.
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An in vitro system for Doppler ultrasound flow studies in the stenosed Carotid Artery Bifurcation.
Ultrasound in Medicine & Biology, 2002Co-Authors: Tamie L Poepping, N. Nikolov, N. Rankin, Mark Lee, David W HoldsworthAbstract:Abstract To investigate the correlation between disease severity and Doppler spectral measurements in the Carotid Artery Bifurcation, a unique in vitro system has been developed that mimics the human vasculature with respect to both anatomy and flow perfusion. Agar-based Carotid phantoms are perfused with a blood-mimicking fluid using a computer-controlled pump and realistic pulsatile flow waveform. A three-axis translational stage allows the lumen to be interrogated with a 0.6-μL Doppler sample volume at the desired spatial intervals using a semiautomated acquisition system, to collect 10 cardiac cycles of gated quadrature data at each site. Off-line analysis, including a 1024-point FFT, produces a 4-D ( i.e., time-varying 3-D) Doppler velocity data set with 1.3-cm/s velocity resolution and 12-ms temporal resolution. Using this system, in vitro flow in Bifurcations with both normal and stenosed lumen geometry (from 30% to 80% stenosis by NASCET criteria) can be studied, along with the effect of factors, such as stenosis geometry (concentric vs. eccentric) and flow rate, on the observed Doppler ultrasound (US) spectra and haemodynamic patterns. (E-mail: dholdswo@irus.rri.ca)
Karl Perktold - One of the best experts on this subject based on the ideXlab platform.
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Flow Characteristics in an Anatomically Realistic Compliant Carotid Artery Bifurcation Model
Computer Methods in Biomechanics and Biomedical Engineering, 1999Co-Authors: Gerhard Karner, Karl Perktold, Michael Hofer, Dieter LiepschAbstract:Abstract A numerical model for the pulsatile blood flow in an anatomically realistic compliant model of the human Carotid Artery Bifurcation has been developed. The geometric model has been generated on the basis of an optically digitized arterial cast. The effects of the geometrically realistic flow domain and of the wall distensibility on the flow characteristics are investigated. The description of the blood flow uses the time-dependent, three-dimensional, incompressible Navier-Stokes equations for non-Newtonian inelastic fluids. The calculation of the wall displacement uses geometrically non-linear shell theory. In an iteratively coupled approach the flow equations and the shell equations are numerically solved using the finite element method. The results show strongly skewed velocity profiles with high gradients at the internal and external divider walls downstream of the Bifurcation. Flow separation and recirculation occur in the regions at the outer walls of the branching during systolic flow decel...
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computer simulation of local blood flow and vessel mechanics in a compliant Carotid Artery Bifurcation model
Journal of Biomechanics, 1995Co-Authors: Karl Perktold, Gerhard RappitschAbstract:Abstract To investigate the effect of the distensible Artery wall on the local flow field and to determine the mechanical stresses in the Artery wall, a numerical model for the blood flow in the human Carotid Artery Bifurcation has been developed. The wall displacement and stress analysis use geometrically non-linear shell theory where incrementally linearly elastic wall behavior is assumed. The flow analysis applies the time-dependent, three-dimensional, incompressible Navier-Stokes equations for non-Newtonian inelastic fluids. In an iteratively coupled approach the equations of the fluid motion and the transient shell equations are numerically solved using the finite element method. The study shows the occurring characteristics in Carotid Artery Bifurcation flow, such as strongly skewed axial velocity in the Carotid sinus with high velocity gradients at the internal divider wall and with flow separation at the outer common-internal Carotid wall and at the Bifurcation side wall. Flow separation results in locally low oscillating wall shear stress. Further strong secondary motion in the sinus is found. The comparison of the results for a rigid and a distensible wall model demonstrates quantitative influence of the vessel wall motion. With respect to the quantities of main interest, it can be seen, that flow separation and recirculation slightly decrease in the sinus and somewhat increase in the Bifurcation side region, and the wall shear stress magnitude decreases by 25% in the distensible model. The global structure of the flow and stress patterns remains unchanged. The deformation analysis shows that the tangential displacements are generally lower by one order of magnitude than the normal directed displacements. The maximum deformation is about 16% of the vessel radius and occurs at the side wall region of the intersection of the two branches. The analysis of the maximum principal stresses at the inner vessel surface shows a complicated stress field with locally high gradients and indicates a stress concentration factor of 6.3 in the apex region.
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Flow and stress characteristics in rigid walled and compliant Carotid Artery Bifurcation models.
Medical & Biological Engineering & Computing, 1994Co-Authors: Karl Perktold, E. Thurner, Th. KennerAbstract:Computer simulation of pulsatile non-Newtonian blood flow has been carried out in different human Carotid Artery Bifurcation models. In the first part of the investigation, two rigid walled models are analysed, differing in the Bifurcation angle (wide angle and acute angle Bifurcation) and in the shape of both the sinus (narrow and larger sinus width) and the Bifurcation region (small and larger rounding of the flow divider), in order to contribute to the study of the geometric factor in atherosclerosis. The results show a significant difference in the wall shear stress and in the flow separation. Flow recirculation in the sinus is much more pronounced in the acute angle Carotid. An important factor in flow separation is the sinus width. In the second part of the study, flow velocity and wall shear stress distribution have been analysed in a compliant Carotid Artery Bifurcation model. In the mathematical model, the non-Newtonian flow field and the idealised elastic wall displacement are coupled and calculated iteratively at each time step. Maximum displacement of approximately 6% of the diastolic vessel diameter occurs at the side wall of the Bifurcation region. The investigation demonstrates that the wall distensibility alters the flow feld and the wall shear stress during the systolic phase. Comparison with corresponding rigid wall results shows that flow separation and wall shear stress are reduced in the distensible wall model.
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three dimensional numerical analysis of pulsatile flow and wall shear stress in the Carotid Artery Bifurcation
Journal of Biomechanics, 1991Co-Authors: Karl Perktold, Michael M Resch, Reinfried Odo PeterAbstract:Abstract To analyse the pulsatile flow field and the mechanical stresses in a three-dimensional Carotid Artery Bifurcation model, computer simulation is applied. The approximation of the Navier-Stokes equations uses a pressure correction finite element method. Numerical results are presented for axial and secondary flow velocity and wall shear stresses with special emphasis on the fluid dynamics in the Carotid sinus. This region is of major interest because it is affected preferentially by lesions. Detailed local flow studies as carried out here should lead to a further insight into the mechanisms of atherogenesis. The flow conditions used in the study were chosen according to Ku et al. ( Arteriosclerosis 5, 293–302, 1985). The results of this numerical analysis agree in the essential features with their experimental results.
David W Holdsworth - One of the best experts on this subject based on the ideXlab platform.
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numerical analysis of the hemodynamic effect of plaque ulceration in the stenotic Carotid Artery Bifurcation
Proceedings of SPIE, 2009Co-Authors: Tamie L Poepping, Emily Y Wong, Jaques S Milner, David A Steinman, David W HoldsworthAbstract:The presence of ulceration in Carotid Artery plaque is an independent risk factor for thromboembolic stroke. However, the associated pathophysiological mechanisms - in particular the mechanisms related to the local hemodynamics in the Carotid Artery Bifurcation - are not well understood. We investigated the effect of Carotid plaque ulceration on the local time-varying three-dimensional flow field using computational fluid dynamics (CFD) models of a stenosed Carotid Bifurcation geometry, with and without the presence of ulceration. CFD analysis of each model was performed with a spatial finite element discretization of over 150,000 quadratic tetrahedral elements and a temporal discretization of 4800 timesteps per cardiac cycle, to adequately resolve the flow field and pulsatile flow, respectively. Pulsatile flow simulations were iterated for five cardiac cycles to allow for cycle-to-cycle analysis following the damping of initial transients in the solution. Comparison between models revealed differences in flow patterns induced by flow exiting from the region of the ulcer cavity, in particular, to the shape, orientation and helicity of the high velocity jet through the stenosis. The stenotic jet in both models exhibited oscillatory motion, but produced higher levels of phase-ensembled turbulence intensity in the ulcerated model. In addition, enhanced out-of-plane recirculation and helical flow was observed in the ulcerated model. These preliminary results suggest that local fluid behaviour may contribute to the thrombogenic risk associated with plaque ulcerations in the stenotic Carotid Artery Bifurcation.
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Medical Imaging: Image-Guided Procedures - Numerical analysis of the hemodynamic effect of plaque ulceration in the stenotic Carotid Artery Bifurcation
Medical Imaging 2009: Visualization Image-Guided Procedures and Modeling, 2009Co-Authors: Emily Y Wong, Tamie L Poepping, Jaques S Milner, David A Steinman, David W HoldsworthAbstract:The presence of ulceration in Carotid Artery plaque is an independent risk factor for thromboembolic stroke. However, the associated pathophysiological mechanisms - in particular the mechanisms related to the local hemodynamics in the Carotid Artery Bifurcation - are not well understood. We investigated the effect of Carotid plaque ulceration on the local time-varying three-dimensional flow field using computational fluid dynamics (CFD) models of a stenosed Carotid Bifurcation geometry, with and without the presence of ulceration. CFD analysis of each model was performed with a spatial finite element discretization of over 150,000 quadratic tetrahedral elements and a temporal discretization of 4800 timesteps per cardiac cycle, to adequately resolve the flow field and pulsatile flow, respectively. Pulsatile flow simulations were iterated for five cardiac cycles to allow for cycle-to-cycle analysis following the damping of initial transients in the solution. Comparison between models revealed differences in flow patterns induced by flow exiting from the region of the ulcer cavity, in particular, to the shape, orientation and helicity of the high velocity jet through the stenosis. The stenotic jet in both models exhibited oscillatory motion, but produced higher levels of phase-ensembled turbulence intensity in the ulcerated model. In addition, enhanced out-of-plane recirculation and helical flow was observed in the ulcerated model. These preliminary results suggest that local fluid behaviour may contribute to the thrombogenic risk associated with plaque ulcerations in the stenotic Carotid Artery Bifurcation.
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An in vitro system for Doppler ultrasound flow studies in the stenosed Carotid Artery Bifurcation.
Ultrasound in Medicine & Biology, 2002Co-Authors: Tamie L Poepping, N. Nikolov, N. Rankin, Mark Lee, David W HoldsworthAbstract:Abstract To investigate the correlation between disease severity and Doppler spectral measurements in the Carotid Artery Bifurcation, a unique in vitro system has been developed that mimics the human vasculature with respect to both anatomy and flow perfusion. Agar-based Carotid phantoms are perfused with a blood-mimicking fluid using a computer-controlled pump and realistic pulsatile flow waveform. A three-axis translational stage allows the lumen to be interrogated with a 0.6-μL Doppler sample volume at the desired spatial intervals using a semiautomated acquisition system, to collect 10 cardiac cycles of gated quadrature data at each site. Off-line analysis, including a 1024-point FFT, produces a 4-D ( i.e., time-varying 3-D) Doppler velocity data set with 1.3-cm/s velocity resolution and 12-ms temporal resolution. Using this system, in vitro flow in Bifurcations with both normal and stenosed lumen geometry (from 30% to 80% stenosis by NASCET criteria) can be studied, along with the effect of factors, such as stenosis geometry (concentric vs. eccentric) and flow rate, on the observed Doppler ultrasound (US) spectra and haemodynamic patterns. (E-mail: dholdswo@irus.rri.ca)
Dem Danielle Palmen - One of the best experts on this subject based on the ideXlab platform.
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analysis of the axial flow field in stenosed Carotid Artery Bifurcation models lda experiments
Journal of Biomechanics, 1996Co-Authors: Frank J. H. Gijsen, Dem Danielle Palmen, Van Der Mhe Maurice Beek, Van De Fn Frans Vosse, Van Meh Rini Dongen, J Jan D JanssenAbstract:Laser Doppler anemometer (LDA) experiments were performed to gain quantitative information on the differences between the large-scale flow phenomena in a non-stenosed and a stenosed model of the Carotid Artery Bifurcation. The influence of the presence of the stenosis was compared to the effect of flow pulse variation to evaluate the feasibility of early detection of stenosis in clinical practice. Three-dimensional Plexiglass models of a non-stenosed and a 25% stenosed Carotid Artery Bifurcation were perfused with a Newtonian fluid. The flow conditions approximated physiological flow. The results of the velocity measurements in the non-stenosed model agreed with the results from previous hydrogen-bubble visualization. A shear layer separated the low-velocity area near the non-divider wall from the high-velocity area near the divider wall. In this shear layer, vortex formation occurred during the deceleration phase of the flow pulse. The instability of this shear layer dictated the flow disturbances. The influences of the mild stenosis, located at the non-divider wall, was mainly limited to the stability of the shear layer. No disturbances were found downstream of the stenosis near the non-divider wall. Using a pulse wave with an increased systolic deceleration time, the velocity distribution showed an extended region with reversed flow, a more pronounced shear layer and increased vortex strength. From these measurements it is obvious that the influence of the presence of a mild stenosis, mainly limited to the stability of the shear layer, can hardly be distinguished from the effects of a variation of the flow pulse. From this it can be concluded that methods for detection of mild stenosis, using solely the large-scale flow phenomena, as can be measured by ultrasound or MRI techniques, will hardly have any clinical relevance.
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Analysis of the axial flow field in stenosed Carotid Artery Bifurcation models—LDA experiments
Journal of Biomechanics, 1996Co-Authors: Frank J. H. Gijsen, Dem Danielle Palmen, Van De Fn Frans Vosse, Van Meh Rini Dongen, Van Der Mhe Maurice Beek, Jd Jan JanssenAbstract:Laser Doppler anemometer (LDA) experiments were performed to gain quantitative information on the differences between the large-scale flow phenomena in a non-stenosed and a stenosed model of the Carotid Artery Bifurcation. The influence of the presence of the stenosis was compared to the effect of flow pulse variation to evaluate the feasibility of early detection of stenosis in clinical practice. Three-dimensional Plexiglass models of a non-stenosed and a 25% stenosed Carotid Artery Bifurcation were perfused with a Newtonian fluid. The flow conditions approximated physiological flow. The results of the velocity measurements in the non-stenosed model agreed with the results from previous hydrogen-bubble visualization. A shear layer separated the low-velocity area near the non-divider wall from the high-velocity area near the divider wall. In this shear layer, vortex formation occurred during the deceleration phase of the flow pulse. The instability of this shear layer dictated the flow disturbances. The influences of the mild stenosis, located at the non-divider wall, was mainly limited to the stability of the shear layer. No disturbances were found downstream of the stenosis near the non-divider wall. Using a pulse wave with an increased systolic deceleration time, the velocity distribution showed an extended region with reversed flow, a more pronounced shear layer and increased vortex strength. From these measurements it is obvious that the influence of the presence of a mild stenosis, mainly limited to the stability of the shear layer, can hardly be distinguished from the effects of a variation of the flow pulse. From this it can be concluded that methods for detection of mild stenosis, using solely the large-scale flow phenomena, as can be measured by ultrasound or MRI techniques, will hardly have any clinical relevance.
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Analysis of the flow in stenosed Carotid Artery Bifurcation models—Hydrogen-bubble visualisation
Journal of Biomechanics, 1994Co-Authors: Dem Danielle Palmen, Van De Fn Frans Vosse, Jd Jan Janssen, Van Meh Rini DongenAbstract:Abstract This paper deals with the effect of geometric changes of mild stenoses on large-scale flow disturbances in the Carotid Artery Bifurcation. Hydrogen-bubble visualisation experiments have been performed in Plexiglas models of a non-stenosed and a 25% stenosed Carotid Artery Bifurcation. The flow conditions approximate physiological flow. The experiments show that shortly after the onset of the diastolic phase vortex formation occurs in the plane of symmetry. This vortex formation is found in a shear layer, which is formed in the Carotid sinus. The shear layer is located between a region with low shear rates at the non-divider wall and a region with high shear rates at the divider wall. In order to gain insight into the parameters that are important with respect to the stability of the shear layer, experiments have been performed in which the influence of the shape of the flow pulse, the Reynolds number (Re), the Womersley parameter (α) and the flow division ratio (γ) on the flow phenomena is studied. From these experiments it appears that the flow phenomena in the Carotid Artery Bifurcation are significantly influenced by Re, α the systolic acceleration (sa) and deceleration (sd) and the duration of the peak-systolic flow (Tmax). With these results a simplified flow pulse is chosen, with which the experiments in the non-stenosed and the 25% stenosed Bifurcation are performed. Comparison of the hydrogen-bubble profiles in the 0 and 25% stenosed models with similar flow conditions shows that the geometric change of the 25% stenosis only slightly influences the flow phenomena. The most striking influences are found in the stability of the shear layer. Quantitative experiments by means of laser Doppler anemometry measurements and numerical computations are needed to analyse the influence of the stenosis of the flow field more accurately.
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LDA measurements in a nonstenosed and a stenosed model of the Carotid Artery Bifurcation
Fifth International Conference on Laser Anemometry: Advances and Applications, 1993Co-Authors: Dem Danielle Palmen, Jd Jan Janssen, F.n. Van De Vosse, Frank J. H. Gijsen, M. E.h. Van DogenAbstract:In order to gain quantitative information of the velocity fields in non-stenosed and stenosed models of the Carotid Artery Bifurcation. Laser Doppler Anemometer (LDA) experiments have been performed. For this purpose a two component backscatter LDA system has been used. The experiments have been conducted in a 1:2.5 enlarged plexiglass model of the Carotid Artery Bifurcation. Both axial and secondary velocities were measured as a function of time at locations of interest. The data were ensemble averaged and analyzed in the frequency domain in order to find characteristic flow phenomena. For the frequency analyses, the transfer functions between velocities at specific sites in the Bifurcation and the input flow signal have been calculated for both the non-stenosed and the stenosed Bifurcation. Both from the results of the velocity fields and the transfer functions, it can be concluded that the main differences between the flow fields in the non-stenosed and the stenosed Bifurcation can be found in an area with high velocity and in a shear layer, which is located at the border between a region with low shear rates at the non-divider wall and a region with high shear rates at the divider wall. The values of the transfer function at these locations seem to be useful for the characterization of the influence of the stenosis.
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Experimental and numerical analysis of the flow in stenosed Carotid Artery Bifurcation models
1993Co-Authors: Dem Danielle Palmen, F.n. Van De Vosse, Frank J. H. Gijsen, Jd Jan JanssenAbstract:In order to gain quantitative information of the variety fields in non-stenosed and stenosed models of the Carotid Artery Bifurcation, Laser Doppler Anemometer (LDA) experiments and finite element computations have been performed. The experiments have been conducted in a 1:2.5 enlarged plexiglass model of the Carotid Artery Bifurcation. Both axial and secondary velocities were measured as a function of time at locations of interest. The date were ensemble averaged and analysed in the frequency domain in order to find characteristic flow phenomena. The numerical computations have been performed by means of a finite element method. Both the experiments and the computations show that a shear layer, which is located at the border between a region with low shear rates at the non-divider wall and a region with high shear rates at the divider wall, is present in the Carotid sinus. In this shear layer, flow disturbances are present at the onset of diastole. The main differences between the flow fields in the non-stenosed and the stenosed Bifurcation are not present downstream of the stenosis but can be found in the shear layer and the area with high velocity
Reinfried Odo Peter - One of the best experts on this subject based on the ideXlab platform.
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three dimensional numerical analysis of pulsatile flow and wall shear stress in the Carotid Artery Bifurcation
Journal of Biomechanics, 1991Co-Authors: Karl Perktold, Michael M Resch, Reinfried Odo PeterAbstract:Abstract To analyse the pulsatile flow field and the mechanical stresses in a three-dimensional Carotid Artery Bifurcation model, computer simulation is applied. The approximation of the Navier-Stokes equations uses a pressure correction finite element method. Numerical results are presented for axial and secondary flow velocity and wall shear stresses with special emphasis on the fluid dynamics in the Carotid sinus. This region is of major interest because it is affected preferentially by lesions. Detailed local flow studies as carried out here should lead to a further insight into the mechanisms of atherogenesis. The flow conditions used in the study were chosen according to Ku et al. ( Arteriosclerosis 5, 293–302, 1985). The results of this numerical analysis agree in the essential features with their experimental results.