In this paper we assume that the blood is to be a Non-Newtonian and incompressible and Homogeneous fluid. An investigation has been done for the resistance to flow across mild stenosis situated symmetrically on steady blood flow through arteries with uniform or non-uniform cross section. An analytical solution for Power law fluid has been obtained. For the physiological insight of the problem various parameters systemic and pulmonary artery are taken and the study reveals that as the height of the stenosis increases in uniform or non-uniform portion of the artery, the resistance parameter and shear stress also steadily increases, whereas, flow rate decreases steadily and we analyze some cases between flux, pressure gradient and radius and give some significant results.
Mathematical Modeling of Bingham Plastic Model of Blood Flow Through Stenotic...IJERA Editor
The aim of the present paper is to study the axially symmetric, laminar, steady, one-dimensional flow of blood through narrow stenotic vessel. Blood is considered as Bingham plastic fluid. The analytical results such as pressure drop, resistance to flow and wall shear stress have been obtained. Effect of yield stress and shape of stenosis on resistance to flow and wall shear stress have been discussed through tables and graphically. It has been shown that resistance to flow and the wall shear stress increase with the size of stenosis but these increase are, however, smaller due to non-Newtonian behaviour of the blood.
PHYSIOLOGICAL NON-NEWTONIAN BLOOD FLOW THROUGH SINGLE STENOSED ARTERYIwate University
Abstract. A numerical simulation to investigate the Non-Newtonian modeling effects on physiological flows in a three dimensional idealized artery with a single stenosis of 85% severity is given. The wall vessel is considered to be rigid. Oscillatory physiological and parabolic velocity profile has been imposed for inlet boundary condition. Determination of the physiological waveform is performed using a Fourier series with sixteen harmonics. The investigation has a Reynolds number range of 96 to 800. Low Reynolds number k − ω model is used as governing equation. The investigation has been carried out to characterize two Non-Newtonian constitutive equations of blood, namely, (i) Carreau and (ii) Cross models. The Newtonian model has also been investigated to study the physics of fluid. The results of Newtonian model are compared with the Non-Newtonian models. The numerical results are presented in terms of velocity, pressure, wall shear stress distributions and cross sectional velocities as well as the streamlines contour. At early systole pressure differences between Newtonian and Non-Newtonian models are observed at pre-stenotic, throat and immediately after throat regions. In the case of wall shear stress, some differences between Newtonian and Non-Newtonian models are observed when the flows are minimum such as at early systole or diastole. In general, the velocities at throat regions are highest at all-time phase. However, at pick systole higher velocities are observed at post-stenotic region. Downstream flow of all models creates some recirculation regions at diastole.
Casson flow of blood through an arterial tube with overlapping stenosisiosrjce
The objective of the present analysis is to study the effect of overlapping stenosis on blood flow
through an artery by taking the blood as Casson type non-Newtonian fluid. The expressions for flux and
resistance to flow have been studied here by assuming the stenosis is to be mild. The results are shown
graphically for different values of yield stress, stenosis length, stenosis height and discussed.
Simulation of Physiological Non-Newtonian Blood Flow through 3-D Geometry of ...Iwate University
Abstract: A numerical simulation has been performed to investigate blood flow behavior of three dimensional idealized carotid arteries. Non-Newtonian flow has been taken for the simulation. The wall of the vessel is considered to be rigid. Physiological and parabolic velocity profile has been imposed for inlet boundary condition. Reynolds number at the inlet has been ranged approximately from 86to 966 for the investigation. Low Reynolds number k-w model has been used as governing equation. The investigations have been carried out to characterize the flow behavior of blood. The numerical results have been presented in terms of wall shear stress distributions, streamlines contours and axial velocity contours. However, highest wall shear stress has been observed in the bifurcation area. Unexpectedly, transient or unstable flow has created flow disturbance regions in the arteries. Moreover, the disturbance of flow has risen as the severity of stenosis in the artery has been increased.
A One-Dimensional Model of a False AneurysmIJRESJOURNAL
ABSTRACT:A false aneurysm is a hematoma, i.e. collection of blood outside of a blood vessel, that forms due to a hole in the wall of an artery. This represents a serious medical condition that needs to be monitored and, under certain conditions, treated urgently. In this work a one-dimensional model of a false aneurysm is proposed. The new model is based on a one-dimensional model of an artery previously presented by the authors and it takes into account the interaction between the hematoma and the surrounding muscle material. The model equations are derived using rigorous asymptotic analysis for the case of a simplified geometry. Even though the model is simple it still supports a realistic behavior for the system consisting of the vessel and the hematoma. Using numerical simulations we illustrate the behavior of the model. We also investigate the effect of changing the size of the hematoma. The simulations show that our model can reproduce realistic solutions. For instance we show the typical strong pulsation of an aneurysm by blood entering the hematoma during the work phase of the cardiac cycle, and the blood returning to the vessel during the resting phase. Also we show that the aneurysm grows if the pulse rate is increased due to, e.g., a higher work load.
Mathematical Modeling of Bingham Plastic Model of Blood Flow Through Stenotic...IJERA Editor
The aim of the present paper is to study the axially symmetric, laminar, steady, one-dimensional flow of blood through narrow stenotic vessel. Blood is considered as Bingham plastic fluid. The analytical results such as pressure drop, resistance to flow and wall shear stress have been obtained. Effect of yield stress and shape of stenosis on resistance to flow and wall shear stress have been discussed through tables and graphically. It has been shown that resistance to flow and the wall shear stress increase with the size of stenosis but these increase are, however, smaller due to non-Newtonian behaviour of the blood.
PHYSIOLOGICAL NON-NEWTONIAN BLOOD FLOW THROUGH SINGLE STENOSED ARTERYIwate University
Abstract. A numerical simulation to investigate the Non-Newtonian modeling effects on physiological flows in a three dimensional idealized artery with a single stenosis of 85% severity is given. The wall vessel is considered to be rigid. Oscillatory physiological and parabolic velocity profile has been imposed for inlet boundary condition. Determination of the physiological waveform is performed using a Fourier series with sixteen harmonics. The investigation has a Reynolds number range of 96 to 800. Low Reynolds number k − ω model is used as governing equation. The investigation has been carried out to characterize two Non-Newtonian constitutive equations of blood, namely, (i) Carreau and (ii) Cross models. The Newtonian model has also been investigated to study the physics of fluid. The results of Newtonian model are compared with the Non-Newtonian models. The numerical results are presented in terms of velocity, pressure, wall shear stress distributions and cross sectional velocities as well as the streamlines contour. At early systole pressure differences between Newtonian and Non-Newtonian models are observed at pre-stenotic, throat and immediately after throat regions. In the case of wall shear stress, some differences between Newtonian and Non-Newtonian models are observed when the flows are minimum such as at early systole or diastole. In general, the velocities at throat regions are highest at all-time phase. However, at pick systole higher velocities are observed at post-stenotic region. Downstream flow of all models creates some recirculation regions at diastole.
Casson flow of blood through an arterial tube with overlapping stenosisiosrjce
The objective of the present analysis is to study the effect of overlapping stenosis on blood flow
through an artery by taking the blood as Casson type non-Newtonian fluid. The expressions for flux and
resistance to flow have been studied here by assuming the stenosis is to be mild. The results are shown
graphically for different values of yield stress, stenosis length, stenosis height and discussed.
Simulation of Physiological Non-Newtonian Blood Flow through 3-D Geometry of ...Iwate University
Abstract: A numerical simulation has been performed to investigate blood flow behavior of three dimensional idealized carotid arteries. Non-Newtonian flow has been taken for the simulation. The wall of the vessel is considered to be rigid. Physiological and parabolic velocity profile has been imposed for inlet boundary condition. Reynolds number at the inlet has been ranged approximately from 86to 966 for the investigation. Low Reynolds number k-w model has been used as governing equation. The investigations have been carried out to characterize the flow behavior of blood. The numerical results have been presented in terms of wall shear stress distributions, streamlines contours and axial velocity contours. However, highest wall shear stress has been observed in the bifurcation area. Unexpectedly, transient or unstable flow has created flow disturbance regions in the arteries. Moreover, the disturbance of flow has risen as the severity of stenosis in the artery has been increased.
A One-Dimensional Model of a False AneurysmIJRESJOURNAL
ABSTRACT:A false aneurysm is a hematoma, i.e. collection of blood outside of a blood vessel, that forms due to a hole in the wall of an artery. This represents a serious medical condition that needs to be monitored and, under certain conditions, treated urgently. In this work a one-dimensional model of a false aneurysm is proposed. The new model is based on a one-dimensional model of an artery previously presented by the authors and it takes into account the interaction between the hematoma and the surrounding muscle material. The model equations are derived using rigorous asymptotic analysis for the case of a simplified geometry. Even though the model is simple it still supports a realistic behavior for the system consisting of the vessel and the hematoma. Using numerical simulations we illustrate the behavior of the model. We also investigate the effect of changing the size of the hematoma. The simulations show that our model can reproduce realistic solutions. For instance we show the typical strong pulsation of an aneurysm by blood entering the hematoma during the work phase of the cardiac cycle, and the blood returning to the vessel during the resting phase. Also we show that the aneurysm grows if the pulse rate is increased due to, e.g., a higher work load.
Shear stress Effects on Left Coronary Artery Saran A K
Throughout the last decade, many studies have found the effect of shear stress on coronary vasculature. Ischaemic Heart Disease is a leading cause of death worldwide, killing an Indian every minute. The most common cause of myocardial ischemia is Atherosclerosis and on the basis of several data, atherosclerosis appears to be more prevalent in the left coronary arterial system compared to the right. The reason for this has remained an enigma for a long while but can be explained by using shear stress. Now, we will see how the shear stress breaks the coronary circuit
In the first part of this study, we identified the existence of a diastolic interval in which intracoronary resistance at rest is equivalent to time-averaged resistance during FFR measurements. We hypothesize that pressure measurements obtained selectively at this specific interval of the cardiac cycle would allow a new pressure-derived index of stenosis severity that does not require pharmacologic vasodilation; we term this the instantaneous wave-free ratio (iFR). In the second part of the study, this hypothesis was tested in a larger population by comparing iFR and FFR measurements.
The property of automaticity of the sinus node is responsible foe the impulse initiation and travels along the cardiac tissue as depolarizations which result in its contraction. So, when activated, the heart is a concentrated locus of time varying potentials in the body. These voltage fluctuations can be measured by the placement of electrodes on the surface of the body. This forms the basis of electrocardiography. In this presentation we will see the basics, the lead systems and the principles behind recording of ECG.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
In this presentation we will discuss normal doppler parameters in portal and hepatic veins and hepatic artery. We will discuss the pathologies regarding hepatic, and portal veins and hepatic artery.
we will discuss Role of sonography in TIPS evaluation.
we will discuss the role of Doppler in post op follow up of hepatic transplant.
More: http://www.pinoybix.org
Lesson Objectives:
Phases of Matter
Density and Specific Gravity
Pressure in Fluids
Atmospheric Pressure and Gauge Pressure
Pascal’s Principle
Measurement of Pressure; Gauges and the Barometer
Buoyancy and Archimedes’ Principle
Fluids in Motion; Flow Rate and the Equation of Continuity
Bernoulli’s Equation
Applications of Bernoulli’s Principle: from Torricelli to Airplanes, Baseballs, and TIA
Viscosity
Flow in Tubes: Poiseuille’s Equation, Blood Flow
Surface Tension and Capillarity
Pumps, and the Heart
Assessment of Intermediate Coronary Artery Lesion with Fractional Flow Reserv...Premier Publishers
Fraction flow reserve (FFR) is considered the gold standard for assessing intermediate coronary lesions. Retrospective data analyses showed variable relationship between intravascular ultrasound (IVUS) parameters and FFR results. This study aimed to determine the optimal minimum lumen area (MLA) by IVUS that correlates with FFR and to assess the correlation between two modalities in assessing intermediate coronary lesions. Methods: Fifty eight intermediate coronary lesions mainly located in proximal and mid segments of large main coronary vessels with RVD (3-4mm) were analyzed using both IVUS and FFR to assess the significance of coronary stenting and to determine the optimal IVUS-MLA that correlates with FFR value < 0.8. Results: IVUS-MLA ranged from 2.5 to 4.2 mm2 had a highly significant positive correlation with FFR value < 0.8 (p < 0.0001). Using the ROC curve analysis, IVUS-MLA < 3.9 mm2 (84.2% sensitivity, 80% specificity, area under curve (AUC) = 0.68) was the best threshold value for identifying FFR <0.8>< 0.8 in coronary vessels with RVD (3-4mm). Different MLA cutoffs should be used for different vessel diameters.
Linearization of Thermo-Viscous Fluid in a Porous Slab Bounded Between two Fi...Editor IJMTER
In this paper the problem of the steady flow of a second order thermo-viscous fluid
through a porous slab bounded between two fixed permeable parallel plates is examined. There is a
constant injection at one plate and equal suction at the other plate. The two plates are kept at two
different temperatures and the flow is generated by a constant pressure gradient. The solutions of
governing equations of the flow with appropriate boundary conditions have been obtained
analytically.
Statistical analysis for measuring the effects of stenotic shapes and spiral ...Iwate University
Numerical simulations have been done for a statistical analysis to investigate the effect of stenotic shapes and spiral flows on wall shear stress in the three-dimensional idealized stenotic arteries. Non-Newtonian flow has been taken for the simulations. The wall of the vessel is considered to be rigid. Physiological, parabolic and spiral velocity profile has been imposed for inlet boundary condition. Moreover, the time-dependent pressure profile has been taken for outlet boundary condition. Reynolds number at the inlet has been ranged approximately from 86 to 966 for the investigation. Low Reynolds number k-w model has been used as governing equation. 120 simulations have been performed for getting the numerical results. However, the numerical results of wall shear stress have been taken for the statistical analysis. The simulations and the statistical analysis have been performed by using ANSYS-18.1 and SPSS respectively. The statistical analyses are significant as p-value in all cases are zero. The eccentricity is the most influencing factor for WSSmax. The WSSmin has been influenced only by the flow spirality. The stenotic length has an influence only on the WSSmax whereas the stenotic severity has an influence on the WSSmax and WSSave.
Shear stress Effects on Left Coronary Artery Saran A K
Throughout the last decade, many studies have found the effect of shear stress on coronary vasculature. Ischaemic Heart Disease is a leading cause of death worldwide, killing an Indian every minute. The most common cause of myocardial ischemia is Atherosclerosis and on the basis of several data, atherosclerosis appears to be more prevalent in the left coronary arterial system compared to the right. The reason for this has remained an enigma for a long while but can be explained by using shear stress. Now, we will see how the shear stress breaks the coronary circuit
In the first part of this study, we identified the existence of a diastolic interval in which intracoronary resistance at rest is equivalent to time-averaged resistance during FFR measurements. We hypothesize that pressure measurements obtained selectively at this specific interval of the cardiac cycle would allow a new pressure-derived index of stenosis severity that does not require pharmacologic vasodilation; we term this the instantaneous wave-free ratio (iFR). In the second part of the study, this hypothesis was tested in a larger population by comparing iFR and FFR measurements.
The property of automaticity of the sinus node is responsible foe the impulse initiation and travels along the cardiac tissue as depolarizations which result in its contraction. So, when activated, the heart is a concentrated locus of time varying potentials in the body. These voltage fluctuations can be measured by the placement of electrodes on the surface of the body. This forms the basis of electrocardiography. In this presentation we will see the basics, the lead systems and the principles behind recording of ECG.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
In this presentation we will discuss normal doppler parameters in portal and hepatic veins and hepatic artery. We will discuss the pathologies regarding hepatic, and portal veins and hepatic artery.
we will discuss Role of sonography in TIPS evaluation.
we will discuss the role of Doppler in post op follow up of hepatic transplant.
More: http://www.pinoybix.org
Lesson Objectives:
Phases of Matter
Density and Specific Gravity
Pressure in Fluids
Atmospheric Pressure and Gauge Pressure
Pascal’s Principle
Measurement of Pressure; Gauges and the Barometer
Buoyancy and Archimedes’ Principle
Fluids in Motion; Flow Rate and the Equation of Continuity
Bernoulli’s Equation
Applications of Bernoulli’s Principle: from Torricelli to Airplanes, Baseballs, and TIA
Viscosity
Flow in Tubes: Poiseuille’s Equation, Blood Flow
Surface Tension and Capillarity
Pumps, and the Heart
Assessment of Intermediate Coronary Artery Lesion with Fractional Flow Reserv...Premier Publishers
Fraction flow reserve (FFR) is considered the gold standard for assessing intermediate coronary lesions. Retrospective data analyses showed variable relationship between intravascular ultrasound (IVUS) parameters and FFR results. This study aimed to determine the optimal minimum lumen area (MLA) by IVUS that correlates with FFR and to assess the correlation between two modalities in assessing intermediate coronary lesions. Methods: Fifty eight intermediate coronary lesions mainly located in proximal and mid segments of large main coronary vessels with RVD (3-4mm) were analyzed using both IVUS and FFR to assess the significance of coronary stenting and to determine the optimal IVUS-MLA that correlates with FFR value < 0.8. Results: IVUS-MLA ranged from 2.5 to 4.2 mm2 had a highly significant positive correlation with FFR value < 0.8 (p < 0.0001). Using the ROC curve analysis, IVUS-MLA < 3.9 mm2 (84.2% sensitivity, 80% specificity, area under curve (AUC) = 0.68) was the best threshold value for identifying FFR <0.8>< 0.8 in coronary vessels with RVD (3-4mm). Different MLA cutoffs should be used for different vessel diameters.
Linearization of Thermo-Viscous Fluid in a Porous Slab Bounded Between two Fi...Editor IJMTER
In this paper the problem of the steady flow of a second order thermo-viscous fluid
through a porous slab bounded between two fixed permeable parallel plates is examined. There is a
constant injection at one plate and equal suction at the other plate. The two plates are kept at two
different temperatures and the flow is generated by a constant pressure gradient. The solutions of
governing equations of the flow with appropriate boundary conditions have been obtained
analytically.
Statistical analysis for measuring the effects of stenotic shapes and spiral ...Iwate University
Numerical simulations have been done for a statistical analysis to investigate the effect of stenotic shapes and spiral flows on wall shear stress in the three-dimensional idealized stenotic arteries. Non-Newtonian flow has been taken for the simulations. The wall of the vessel is considered to be rigid. Physiological, parabolic and spiral velocity profile has been imposed for inlet boundary condition. Moreover, the time-dependent pressure profile has been taken for outlet boundary condition. Reynolds number at the inlet has been ranged approximately from 86 to 966 for the investigation. Low Reynolds number k-w model has been used as governing equation. 120 simulations have been performed for getting the numerical results. However, the numerical results of wall shear stress have been taken for the statistical analysis. The simulations and the statistical analysis have been performed by using ANSYS-18.1 and SPSS respectively. The statistical analyses are significant as p-value in all cases are zero. The eccentricity is the most influencing factor for WSSmax. The WSSmin has been influenced only by the flow spirality. The stenotic length has an influence only on the WSSmax whereas the stenotic severity has an influence on the WSSmax and WSSave.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
ANALYSIS OF FLOW CHARACTERISTICS OF THE BLOOD THROUGH CURVED ARTERY WITH MIL...indexPub
Narrowing of the arteries caused by atherosclerosis reduces blood flow to the heart, which results shows ischemia, angina pectoris, cerebral strokes, and other coronary artery disease signs and symptoms. Curvature is seen in blood vessels at various locations. The stenotic surface provides an additional curvature and the point of maximum shear which varies with the cross-section. A cylindrical form of the Navier-Stokes equations in polar coordinate system have been extended to include dynamic curvature along the axial direction. The blood flow behavior of taking different values of blood parameters like viscosity, the radius of the artery, and the thickness of the stenosis has been studied with and without curvature by using an extended blood flow model with dynamic curvature. Moreover, the aspects of blood flow, such as dynamic curvature velocity profile, volumetric flow rate, pressure drop, and shear stress, have been studied in relation to blood flow around curved arteries with stenosis, variations in the radii of the artery, thickness of the stenosis, and viscosity. The information may reveal that by increasing the values of curvature, viscosity, and thickness of stenosis, velocity, and volumetric flow rate can be quickly reduced. Increasing the curvature, viscosity, and thickness of stenosis also results in an increase in shear stress and a pressure drop. The presence of curved stenotic arteries has a significant impact on the flow parameters, and it is crucial to know about these dynamics in order to study the cardiovascular system.
Murmurs from the Vascular Members: A Generalized Theoretical Outlook IIJSRJournal
Stenosis-induced turbulence can bring many insidious effects to bear on the vasculature. The sound generated in an arterial compartment due to fluctuating turbulent pressure and the distortions in the flow characteristics around a stenotic region leave much to be desired. As vascular sounds are generated locally in the peripheral blood vessels, they require near-field auscultation. It is commonplace in clinical practice to place premium on near-field auscultation, with little attention to events in the far field. Nevertheless, retrograde waves that travel some distance away from the vicinity of the acoustic source require attention. They create an incipient murmur that pervades from a distance well before the source point on impact with the advancing anterograde wave. This paper, a theoretical study on vascular murmurs, utilized the concept of acoustic power spectrum and Lighthill’s acoustic analogy in describing vascular murmurs. Apologies for far-field acoustic auscultation are made since in-situ-generated vascular sounds may travel beyond the near field.
Effect of Magnetic Field on Blood Flow (Elastico- Viscous) Under Periodic Bod...IOSR Journals
Aim of this study is to investigate the effect of magnetic field on blood flow in cylindrical artery through porous medium. In this paper blood is considered elastico viscous, Non Newtonian fluid and flow is assumed as fully developed and laminar. Laplace transforms and Finite Hankel Transforms are used to obtain the analytical expression for velocity profile, flow rate and fluid acceleration. The effect of magnetic field on velocity and fluid acceleration has been discussed with the help of graphs. It is found that velocity distribution, flow rate and fluid acceleration of blood in cylindrical artery decrease as magnetic field increases.
The International Journal of Engineering and Science (The IJES)theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Analytical Study of A Two-Phase Model For Steady Flow of Blood in A Circular ...IJERA Editor
The present paper deals with a mathematical model of blood flow through narrow circular tube. The model consists of a core region of suspension of all the erythrocytes assumed to be a power law fluid and a peripheral cell-depleted layer of plasma as a Newtonian fluid. The system of differential equations has been solved analytically. The expressions for velocity profile, Bluntness parameter, flow rate, the ratio of core hematocrit to discharge hematocrit (Hc/HD), apparent viscosity (μapp), and the ratio of tube hematocrit to discharge hematocrit (HT/HD) and shear stress at the wall have obtained. Some of them have been discussed through graphs.
Study on viscosity induced contrast in ultrasound color flow imaging of carot...IJECEIAES
Efficient imaging of blood flow disturbances resulted from carotid atherosclerosis plays a vital role clinically to predict brain stroke risk. Carotid atherosclerosis and its development is closely linked with raised blood viscosity. Therefore, study of viscosity changing hemodynamic effect has importance and it might be useful for improved examination of carotid atherosclerosis incorporating the viscosity induced contrast in conventional ultrasound imaging. This work considered the design of realistic models of atherosclerotic carotid artery of different stages and solved to compute the hemodisturbances using computational fluid dynamics (CFD) by finite element method (FEM) to investigate viscosity changes effect. Ultrasound color flow image of velocities of blood have been constructed using phase shift information estimated with autocorrelation of Hilbert transformed simulated backscattered radiofrequency (RF) signals from moving blood particles. The simulated ultrasound images have been compared with CFD simulation images and identified a good match between them. The atherosclerosis stages of the models have been investigated from the estimated velocity data. It has been observed that the blood velocities increase noticeably in carotid atherosclerotic growths and velocity distribution changes with viscosity variations. It is also found importantly that the viscosity induced contrast associated to atherosclerosis is detectable in ultrasound color flow imaging. The findings of this work might be useful for better investigation of carotid atherosclerosis as well as prediction of its progression to reduce the stroke risk.
Effect Of Elasticity On Herschel - Bulkley Fluid Flow In A TubeIJARIDEA Journal
Abstract— The impact of flexibility on Herschel-Bulkley liquid in a tube is researched. The issue is unraveled scientifically
for two unique sorts: one flux is computed taking the worry of the flexible tube into thought and the other flux is acquired by
considering the weight range relationship. Speed of the inelastic tube is additionally considered. The impact of various
parameters on flux and speed are talked about through charts. The outcomes acquired for the stream attributes uncover
many intriguing practices that warrant additionally contemplate on the non-Newtonian liquid stream wonders, particularly
the shear-diminishing marvels. Shear diminishing decreases the divider shear stretch.
Keywords— Elastic tube, Herschel-Bulkley Fluid, Inlet pressure, Outlet Pressure, Yield Stress.
Peristaltic flow of blood through coaxial vertical channel with effect of mag...ijmech
The present paper investigates the effects of peristaltic flow of blood through coaxial vertical channel with
effect of magnetic field: blood flow study.The effects of various physical parameters on axial velocity and
pressure gradient have been computed numerically. It is observed that the maximum velocity increases
with increase in Magnetic field (M) even though for phase shiptııııı/ 4 for all the two cases
= - 0.5,
= -1. However, opposite effects are noticed for
= 0.5,
= 1.
EFFECT OF NEGATIVE ANGLE CANNULATION DURING CARDIOPULMONARY BYPASS – A COMPUT...ijbesjournal
Creation of emboli in the aortic root and changes in flow distribution between supra-aortic arteries and descending aorta can lead to stroke and perfusion related tissue damage during cardiopulmonary bypass. A thorough understanding of how the angle of cannulation affects the overall success of cardiopulmonary bypass during cannulation of the ascending aorta is needed. Previous simulation research has observed the effect of outflow cannula position by changing the location of the cannulation site to the subclavian artery and other vessels, as well as positions for innovative cannula designs. The purpose of this study is to evaluate the success of the procedure while using a straight cannula, modulating the angle of cannulation below horizontal in the frontal plane. A simplified geometry of the aorta was used. The success of the procedure was quantified by observing wall shear stress, normal stress, intra-fluid shear stress, and flow distribution. A numerical study was performed to solve the Reynolds Averaged Naiver Stokes governing equations, which were used in conjunction with a constant density fluid to simulate blood, and a realizable two-layer k-ε turbulence model
Design and Analysis of Hydraulic Actuator in a Typical Aerospace vehicle | J4...Journal For Research
An Aerospace Vehicle is capable of flight both within and outside the sensible atmosphere. An Actuation System is one of the most important Systems of an Aerospace vehicle. This paper study involves detailed study of various controls Actuation System and Design of a typical Hydraulic Actuation Systems. An actuator control system concerned with electrical, electronic or electro mechanical. Actuator control systems may take the form of extremely simple, manually-operated start-and-stop stations, or sophisticated, programmable computer systems. Hydraulic Actuation System contains Electro Hydraulic Actuators, Servo Valves, Feedback Sensing elements, Pump Motor package, Hydraulic Reservoir, Accumulator, various safety valves, Filters etc. The main objective of this study involves design of Hydraulic Actuator and selection of various other components for the Actuation Systems of an Aerospace Vehicle. Design of the system includes design of Hydraulic actuator and also the Modeling and Analysis of actuator using sophisticated Software.
Experimental Verification and Validation of Stress Distribution of Composite ...Journal For Research
Now a day in all sector weight reduction is most important criteria for lowering the cost & high performance. For weight reduction composite material is good option to solve weight related problems. In this paper we describe analysis of composite glass fibre material with mild steel material comparison. For analysis purpose we can use FEA software. The objective of this paper is compare things like different loading conditions stress distribution etc.
Image Binarization for the uses of Preprocessing to Detect Brain Abnormality ...Journal For Research
Computerized MR of brain image binarization for the uses of preprocessing of features extraction and brain abnormality identification of brain has been described. Binarization is used as intermediate steps of many MR of brain normal and abnormal tissues detection. One of the main problems of MRI binarization is that many pixels of brain part cannot be correctly binarized due to the extensive black background or the large variation in contrast between background and foreground of MRI. Proposed binarization determines a threshold value using mean, variance, standard deviation and entropy followed by a non-gamut enhancement that can overcome the binarization problem. The proposed binarization technique is extensively tested with a variety of MRI and generates good binarization with improved accuracy and reduced error.
A Research Paper on BFO and PSO Based Movie Recommendation System | J4RV4I1016Journal For Research
The objective of this work is to assess the utility of personalized recommendation system (PRS) in the field of movie recommendation using a new model based on neural network classification and hybrid optimization algorithm. We have used advantages of both the evolutionary optimization algorithms which are Particle swarm optimization (PSO) and Bacteria foraging optimization (BFO). In its implementation a NN classification model is used to obtain a movie recommendation which predict ratings of movie. Parameters or attributes on which movie ratings are dependent are supplied by user's demographic details and movie content information. The efficiency and accuracy of proposed method is verified by multiple experiments based on the Movie Lens benchmark dataset. Hybrid optimization algorithm selects best attributes from total supplied attributes of recommendation system and gives more accurate rating with less time taken. In present scenario movie database is becoming larger so we need an optimized recommendation system for better performance in terms of time and accuracy.
IoT based Digital Agriculture Monitoring System and Their Impact on Optimal U...Journal For Research
Although precision agriculture has been adopted in few countries, the greenhouse based modern agriculture industry in India still needs to be modernized with the involvement of technology for better production and cost control. In this paper we proposed a multifunction model for smart agriculture based on IoT. Due to variable atmospheric circumstances these conditions sometimes may vary from place to place in large farmhouse, which makes very difficult to maintain the uniform condition at all the places in the farmhouse manually. Soil and environment properties are sensed and periodically sent to cloud network through IoT. Analysis on cloud data is done for water requirement, total production and maintaining uniform environment conditions throughout greenhouse farm. Proposed model is beneficial for increase in agricultural production and for cost control and real time monitoring of farm.
A REVIEW PAPER ON BFO AND PSO BASED MOVIE RECOMMENDATION SYSTEM | J4RV4I1015Journal For Research
Recommendation system plays important role in Internet world and used in many applications. It has created the collection of many application, created global village and growth for numerous information. This paper represents the overview of Approaches and techniques generated in recommendation system. Recommendation system is categorized in three classes: Collaborative Filtering, Content based and hybrid based Approach. This paper classifies collaborative filtering in two types: Memory based and Model based Recommendation .The paper elaborates these approaches and their techniques with their limitations. The result of our system provides much better recommendations to users because it enables the users to understand the relation between their emotional states and the recommended movies.
HCI BASED APPLICATION FOR PLAYING COMPUTER GAMES | J4RV4I1014Journal For Research
This paper describes a command interface for games based on hand gestures and voice command defined by postures, movement and location. The system uses computer vision requiring no sensors or markers by the user. In voice command the speech recognizer, recognize the input from the user. It stores and passes command to the game, action takes place. We propose a simple architecture for performing real time colour detection and motion tracking using a webcam. The next step is to track the motion of the specified colours and the resulting actions are given as input commands to the system. We specify blue colour for motion tracking and green colour for mouse pointer. The speech recognition is the process of automatically recognizing a certain word spoken by a particular speaker based on individual information included in speech waves. This application will help in reduction in hardware requirement and can be implemented in other electronic devices also.
A REVIEW ON DESIGN OF PUBLIC TRANSPORTATION SYSTEM IN CHANDRAPUR CITY | J4RV4...Journal For Research
As we know the population of Chandrapur City has increased so far in this years and with that has increased the vehicles causing high traffic volume & rise in pollution. But the transportation system in Chandrapur City is still the same. To reduce the traffic volume & pollution, we have to study & design the new transportation system in Chandrapur City. The system would be as similar to Nagpur City with the implementation of Star City Buses. In this Study we would first compare the speed of various vehicles. Collection of population details of Chandrapur City, approximate number of vehicles running on road, collection of data with respect to Ticket fares in Nagpur City- whether it is according to Kilometers or places to be reached, calculation of Ticket Fares for Chandrapur City on the basis data collected. By all these, the best mode of transport in City can be studied. On the basis of above data collected from various respected fields, we will then proceed for the Design part of urban transport system in Chandrapur City. For Design purpose, firstly we have to mark the centre of the City, when the centre is decided; we will then select the Bus Terminus. From centre of the city, we would prefer to select the routes of the Buses. One route will be for the city side like Jatpura Gate, Pathanpura Gate. One route will be for Ballarpur going road. The other one for Mul going road, then next for Nagpur road. We could decide as many routes once we get the clear idea about all data. By getting all this details, the next step is to design the destination points of Buses. Then we have to design about the Bus bays, to reduce congestion in the particular intersections or Stops of bus. After the design also can suggest for Bus lanes. Implementation of Bus Rapid Transit System (BRT system) is the main aim behind to develop transportation mode of City. The design of the Transport System can be designed with the help of various software’s like AutoCAD and Revit.
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Sandstones from seven different hydroelectric projects have been assessed to compare their water-related properties and engineering parameters and the comprehensive analysis has been presented. The study has been done by categorizing the sandstones in to three categories i.e. weak, moderate & strong sandstones. The study leads to four broad inferences: (1), there could be very large variation between two sandstones; e.g., here, sandstone S2, S4 & S5, vis-à-vis other two strong sandstones, is superior in all respects. (2), the four weak sandstones differ in respect of some – not all – properties and parameters. (3), none of the four weak sandstones is better than the other two in respect of all properties and parameters. (4), moderate sandstone shows higher values of shear strength parameters in comparison to all the sandstones (including stronger sandstones also) except S3 strong sandstone. In respect of individual properties, the grain density of all sandstones is similar, though their bulk densities, apparent porosity and water content show great variation. The weak, moderate and strong sandstones show qualitative difference in their uniaxial compressive strength and wave velocity (compression and shear, both); and the two are directly proportional. The study clearly demonstrates that there is no one-to-one correspondence between any two properties and parameters, but there is a diffused and/ or qualitative relationship between different sandstones, or certain properties and parameters of a particular variant.
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DakNet, is an ad hoc network and an internet service planted on the applied science, which uses wireless technology to provide an asynchronous digital connectivity, it is the intermediate of wireless and asynchronous service that is the beginning of a technical way to universal broadband connectivity. The major process is it provides the broadband connectivity as wider. This paper broadly describes about the technology, architecture behind and its working principles.
Line following is one of the most important aspects of Robotics. A Line Follower Robot is an autonomous robot which is able to follow either a black or white line that is drawn on the surface consisting of a contrasting color. It is designed to move automatically and follow the made plot line. The path can be visible like a black line on a white surface or it can be invisible like a magnetic field. It will move in a particular direction Specified by the user and avoids the obstacle which is coming in the path. Autonomous Intelligent Robots are robot that can perform desired tasks in unstructured environments without continuous human guidance. It is an integrated design from the knowledge of Mechanical, Electrical, and Computer Engineering. LDR sensors based line follower robot design and Fabrication procedure which always direct along the black mark on the white surface. The robot uses several sensors to identify the line thus assisting the bot to stay on the track. The robot is driven by DC motors to control the movements of the wheels.
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AN INTEGRATED APPROACH TO REDUCE INTRA CITY TRAFFIC AT COIMBATORE | J4RV4I1002Journal For Research
Coimbatore (11.0168°N,76.9558°E) is a fast developing cosmopolitan city with large number of industries and educational institutions. The development has lead to a large number of vehicles causing heavy traffic. The traffic congestion at Coimbatore has been a major problem which causes traffic jams and accidents. The major reason for traffic has been the mofussil buses that operate in the city. Around 1300 mofussil buses enter into the city, these buses play an important role in traffic congestion. The best solution is to construct a centralized bus stand at the outskirts of the city. This would reduce the traffic, accidents and also leads to development of the outskirts of the city. A suitable location near the city with sufficient road access to connecting cities has been chosen and the bus terminus has been designed, modeled with all facilities and features.
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Cyclone is the most commonly used device to separate dust particles from gas and dust flow. The performance of cyclone separator can be measured in terms of collection efficiency and pressure drop. Parameters like Inlet Flow velocity, the particle size distribution in feed, dimensions of inlet and outlet ducts and cyclone affects the performance of cyclone significantly. Various Mathematical models used for calculation of cut off diameter of separator, flow rate, target efficiency and no. of vortex inside the cyclone to design and study to check the performance of existing cyclone separator. Also new dimensions can be design with help of models. Here, in this study the efficiency achieved with Lapple model cumulatively 86.47%.
During past few years, brain tumor segmentation in CT has become an emergent research area in the field of medical imaging system. Brain tumor detection helps in finding the exact size and location of tumor. An efficient algorithm is proposed in this project for tumor detection based on segmentation and morphological operators. Firstly quality of scanned image is enhanced and then morphological operators are applied to detect the tumor in the scanned image. The problem with biopsy is that the patient has to be hospitalized and also the results (around 15%) give false negative. Scan images are read by radiologist but it's a subjective analysis which requires more experience. In the proposed work we segment the renal region and then classify the tumors as benign or malignant by using ANFIS, which is a non-invasive automated process. This approach reduces the waiting time of the patient.
USE OF GALVANIZED STEELS FOR AUTOMOTIVE BODY- CAR SURVEY RESULTS AT COASTAL A...Journal For Research
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2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
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EFFECTS OF STENOSIS ON POWER LAW FLUID FLOW OF BLOOD IN BLOOD VESSELS
1. Journal for Research| Volume 01| Issue 09 | November 2015
ISSN: 2395-7549
All rights reserved by www.journalforresearch.org 23
Effects of Stenosis on Power Law Fluid Flow of
Blood in Blood Vessels
Subhash Chandra Pragya Singh
Department of Mathematical Science Department of Mathematical Science
Indian Institute of Technology (Baranas Hindu University),
Varanasi 221002, India
Indian Institute of Technology (Baranas Hindu University),
Varanasi 221002, India
Rana Waleed Bhnam Hndoosh
Department of Software Engineering
College of Computers Sciences & Mathematics, Mosul University, Iraq
Abstract
In this paper we assume that the blood is to be a Non-Newtonian and incompressible and Homogeneous fluid. An investigation
has been done for the resistance to flow across mild stenosis situated symmetrically on steady blood flow through arteries with
uniform or non-uniform cross section. An analytical solution for Power law fluid has been obtained. For the physiological insight
of the problem various parameters systemic and pulmonary artery are taken and the study reveals that as the height of the
stenosis increases in uniform or non-uniform portion of the artery, the resistance parameter and shear stress also steadily
increases, whereas, flow rate decreases steadily and we analyze some cases between flux, pressure gradient and radius and give
some significant results.
Keywords: Resistance Parameter, Arterial Stenosis, Power Law Fluid, Wall Shear Stress, Flux, Pressure Gradient,
Pulmonary Artery, Flow Rate
_______________________________________________________________________________________________________
I. INTRODUCTION
Diseases in the blood vessels and in the heart, such as heart attack and stroke, are the major causes of mortality worldwide. The
underlying cause for these events is the formation of lesions, knows as atherosclerosis, in the large and medium sized arteries in
the human circulation.
The term stenosis or we can say that the deposit of cholesterol is the development of arteriosclerotic or other types of
abnormal tissue development. When stenosis is constructed in artery then blood flow is obstructed. Stenosis could affect one or
more segments of the human cardiovascular system studies on initiation and growth of stenosis (arteriosclerotic plaques) in the
human cardiovascular system have been carried out from several view-points. Arteriosclerosis is a common disease, which
severely influences human health. Our body is made up of miles and miles of hollow tubes. Many small and large hollow space
and even well establish and reinforce canals. It has been found that the initiation and localization of arteriosclerosis is closely
related to local heamodynamic factors. Due to these serious consequences, attention has been given in studies of blood flow in
stenosis region under different conditions. Different mathematical models have been studied by some researchers to explore the
various aspects of blood flow in stenosed artery (Smith et al. 2002 and Shukla et al. (1980a, b). Srivastava (2002) investigated
the effects of stenosis shape and red cell concentration (hematocrit) on blood flow characteristics due to the presence of stenosis.
Ponalagusamy (2007) considered a mathematical model for blood flow through stenosed arteries with axially variable peripheral
layer thickness and variable slip at the wall. Mishra et al. (2010) studied that as the height of the stenosis increases in blood
vessels, the shear stress and resistance parameter steadily increases whereas, flow rate decreases steadily.
Fig. 1: Blood Artery Fig. 2: Stenosis in Artery
2. Effects of Stenosis on Power Law Fluid Flow of Blood in Blood Vessels
(J4R/ Volume 01 / Issue 09 / 005)
All rights reserved by www.journalforresearch.org 24
Fig. 3: Bone in our Spines May Harden and Become Overgrown
As we age, the bone in our spines may harden and become overgrown. This can lead to a narrowing of the spinal canal, called
stenosis
Fig. 4: blocked in the right coronary artery Fig. 5: Development of atherosclerotic plaques
Fig. 6: Geometry of Tube with Multi Stenosis
In this paper, blood is assumed to be Non-Newtonian, incompressible and homogeneous fluid; cylindrical polar co-ordinate is
used, with the axis of symmetry of artery taken as Z -axis. The stenosis is mild and the motion of the fluid is laminar and steady.
The inertia term is neglected, as the motion is slow. No body force acts on the fluid and there is no slip at the wall.
II. NOMENCLATURE
Density of blood, Viscosity of blood, p Pressure, 1R Radius of uniform portion of tube, R z Radius of
obstructed portion of tube, R ns z Radius of obstructed portion of due to the nth
stenosis of tube, ns Amplitude of nth
stenosis, nL = Length of nth
stenosis, nd Location of nth stenosis, nl Length of uniform portion of tube, l Length of tube,
K Wall exponent parameter, Wall shear stress, 0 Measure of yield stress, e Strain late du
dr
, u Velocity of
3. Effects of Stenosis on Power Law Fluid Flow of Blood in Blood Vessels
(J4R/ Volume 01 / Issue 09 / 005)
All rights reserved by www.journalforresearch.org 25
fluid, cR Radius of the core region of the tube, Resistance to flow at the wall for the flow of blood, 0 Resistance to
flow at the wall for the flow of blood in uniform portion of tube, '
Resistance parameter
We assume the following non- dimensional quantities:
' ' ' ' ' ' ' '1 1
1 1
1 0
, , , , , , 'n n
n n n
R zd L l Rz z
Z d L l S R z R
l l l l l R l
III.BASIC EQUATIONS
In the present analysis, it is assumed that the stenosis develops in the arterial wall in an axially symmetric manner and depends
upon the axial distance z, and the height of its growth (figure 9). In such a case the radius of the artery, ,R z (by Young and
Tsai (1973a, b)) can be written as follows:
1 1 1 1 1 1;0 &sR Z R z R z d d L z l
1
1 1
1 1 1 1 1
1
2
1 cos ;
2 2
s
s L
R Z R z R z d d z d L
L
2 2 1 2 2 2; &sR Z R z R z l z d d L z l …… (1)
2
2 2
2 2 2 2 2
2
2
1 cos ;
2 2
s
s L
R Z R z R z z d d z d L
L
2
1
1 1;K z l
R Z R e l z l
………. (2)
For the steady flow through circular artery, the wall shear stress is given by,
22
rGdz
dp
r
… (3)
Where,
dp
G
dz
is the pressure gradient … (4)
The flow rate Q through the artery, is the sum of the flow through the core region and that in the peripheral region, i.e.,
core peripheralQ Q Q … (5)
Where the flow rate through the core and peripheral region respectively is given by
2
core c cQ u R
… (6)
2
c
R
peripheral
R
Q urdr
… (7)
Tne resistance to flow at the wall for the flow of blood can also be expressed as
Q
dp
Development of the Model:A.
The constitutive relationship for the power fluid is given by the relationship
n
e ; 1n … (8)
The velocity of the fluid through the tube thus can be expressed in terms of
2
n
rG du
dr
11
2 1
n
nnG nr
u C
n
… (9)
Where C is constant of integration.
Applying the boundary conditions 0; ,u r R we have
1
( 1)/
2 1
n nn
G nR
C
n
… (10)
Thus the velocity of the fluid in the tube is given by equation (11)
4. Effects of Stenosis on Power Law Fluid Flow of Blood in Blood Vessels
(J4R/ Volume 01 / Issue 09 / 005)
All rights reserved by www.journalforresearch.org 26
1
(n 1)/n ( 1)/
R
2 1
n
n nG n
u r
n
… (11)
The flow through the artery can be obtained from the basic equation
0
2
R
Q urdr
… (12)
For 1
,
2
n we get the expression of flow through the blood vessel as
2
5 2 ' '
1 1 1 1 1 2 22
5 5
20
P
Q R l Kl l l s L L
… (13)
Also the expression of wall shear stress through the blood vessel is given in equation (14)
2 2 2
3
' '1 1 22
1 1 1 1 1 2 2 22 2
1 2
3 3
{ } 1 1 ( )
2 2 2 2
kl L L
R l l l s L d s L d
L L
… (14)
For 1
,
3
n resistance to flow at the wall for the flow of blood is given by
3
16 6
0
48 2 2
l
cR R dz
The resistance to flow at the wall for the flow of blood in uniform portion of blood vessel is,
3
16 6
0 1
0
48 2 2
l
cR R dz
Thus the resistance parameter for the flow of blood in the blood vessel is expressed as
3' 6 ' ' 6 6 ' ' '
1 1 1 2 2 1 2 11 6 1 6 1 2c c cl L L s R L s R R l l L K l l … (15)
Effect of Wall Shear Stress:B.
Power law model
'
1S
K = 0.001 K = 0 K = - 0.001
.027 35.324 20.174 5.024
.034 38.354 23.20 8.050
.040 41.384 26.234 11.084
.046 44.414 29.264 14.114
.053 47.444 32.294 17.144
.060 50.474 35.324 20.174
Table 1: Variation of against '
1S for K = -0.001, 0, 0.001.
Effect of Flow Rate:C.
Power law model
'
1S Q
K = 0.001 K = 0 K = -0.001
.027 40.48 39.89 39.24
.034 40.41 39.77 39.21
.040 40.37 39.74 39.17
.046 40.33 39.72 39.12
.053 40.30 39.69 39.07
.060 40.25 39.64 39.04
Table 2: Variation of Q against '
1S for K = -0.001, 0, 0.001
Effect of Resistance Parameter:D.
Power law modal
'
2S '
K = -0.001 K = 0 K=0.001
.027 5.150996 5.0028200003 4.854644
.034 5.151416 5.0032400003 4.855064
.040 5.151776003 5.003600003 4.855424003
.046 5.152136 5.003960003 4.855784
.053 5.152556003 5.0043800003 4.856204003
5. Effects of Stenosis on Power Law Fluid Flow of Blood in Blood Vessels
(J4R/ Volume 01 / Issue 09 / 005)
All rights reserved by www.journalforresearch.org 27
.060 5.152976003 5.0048000003 4.856624003
.067 5.153126001 5.005200003 4.856927003
Table 3: Variation of '
against '
2S for K = -0.001, 0, 0.001
We assume one stenosis each in uniform and non- uniform portion of the artery (Figure 6). To observe explicitly the effect of
various parameters on resistance, wall shear stress and viscosity to the flow, the following function has been assumed for the
artery radius, which is non- uniform.
Fig. 7: Variation of against '
1s for various value of K
Fig. 8: Variation of Q against
'
1s for various value of K
Fig. 9: Variation of
'
against
'
2s for various value of K
Effect of Various Parameters on the Flow of Blood in Stented Blood Vessels:E.
In order to get a physiological insight into the effect of stenosis on the wall shear stress, flow rate and resistance parameter
against '
1S or '
2S or both, for different values of wall exponent parameter K, i.e. K>0(divergence of artery), K=0(uniform
portion of capillary) and K<0(convergence of veins), computations are made for power law model are shown in the below
sections.
Analysis:1)
In the Power law model developed, we observe that as the height of stenosis increases in the blood vessels, wall shear stress also
steadily increases for different values of wall exponent parameter, i.e. K>0(divergence of artery), K=0(uniform portion of
capillary) and K<0(convergence of veins). The mean arterial blood pressure (MAP) in arteries is around 100mm Hg, in the
capillaries the MAP is 25mm Hg and in the veins and venae-cavae its mean pressure falls progressively to about 0 mm Hg in the
systemic circulation. Similarly in the pulmonary circulation the MAP is 16 mm Hg, whereas, in the pulmonary capillary it is 7
6. Effects of Stenosis on Power Law Fluid Flow of Blood in Blood Vessels
(J4R/ Volume 01 / Issue 09 / 005)
All rights reserved by www.journalforresearch.org 28
mm Hg and in the pulmonary veins its mean pressure falls progressively to about 0 mm Hg like in systemic circulation. The
above model depict the physiological conditions like K>0, K=0 and K<0.
Analysis:2)
In the Power law model developed, we observe that as the height of the stenosis increases in the blood vessels, flow rate steadily
decreases for different values of wall exponent parameter, i.e., K<0(convergence of artery), K=0(uniform portion of artery) and
K>0(divergence of artery).
In the above model developed, we observe that as the height of stenosis increases in the blood vessels, resistance parameter
steadily increases for different values of wall exponent parameter, i.e. K<0(convergence of artery), K=0(uniform portion of
artery) and K>0(divergence of artery).
IV.DISCUSSION
Wall shear stress is an important factor in the study of blood flow. Accurate predictions of the distribution of the wall shear stress
are particularly useful for the understanding of the effect of blood flow on endothelial cells. However, the flow rate in the arteries
is affected much compared to veins, as arteries are resistance vessels, whereas veins are capacitance vessels. In hypertensive
patients, the sustained increased pressure in arteries will lead to remodeling of the blood vessels and heart, especially in the
resistance vessels where the pressure is very high. Arteries tend to become less elastic and stiff. In the model discussed, the
trends observed show that as the stenosis increases there is an increase in the MAP in the resistance vessels which may lead to
remodeling of the arteries. The remodeling is not prominent in capillaries and veins, where the resistance to flow is least
parameter compared to arteries. In the model developed above, we observe that Power law fluid model well suit for the
physiological data.
V. CONCLUSION
The study reveals that as the height of the stenosis increases in the uniform or non- uniform or both portions of the artery the
resistance to the flow also increases.
Physical Significance:A.
Model can help the user understand the spread of a disease and then specify the question that needs to be answered, and identify
important data needs, including regular surveillance and outbreak investigations. Which can help health officials focus on critical
factors.
ACKNOWLEDGEMENT
I am also thankful to my brother Mr. Sanjay Kumar for his moral support and belief in my abilities!
REFERENCES
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[2] Shukla, J. B., Parihar, R. S.; Rao, B. R. P. and Gupta, S.P. (1980b) “Effect of peripheral layer viscosity on peristaltic transport of a biofluid.” J. Fluid
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[7] Young, D. F. and Tsai, F. Y. (1973a) “Flow characteristic in model of arterial stenosis-I.” J. Biomechanics, 6: 395-410.
[8] Young, D. F. and Tsai, F. Y. (1973b) “Flow characteristic in model of arterial stenosis-II.” J. Biomechanics, 6: 547-599.
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