scholarly journals Computational Modelling of Blood Flow Development and Its Characteristics in Magnetic Environment

2013 ◽  
Vol 2013 ◽  
pp. 1-12
Author(s):  
Gopal Chandra Shit

Of concern in this paper is an investigation of the entrance length behind singularities in cardiovascular hemodynamics under magnetic environment. In order to get better interpretation of scan MRI images, the characteristics of blood flow and electromagnetic field within the circulatory system have to be furthermore investigated. A 3D numerical model has been developed as an example of blood flowing through a straight circular tube. The governing coupled nonlinear differential equations of magnetohydrodynamic (MHD) fluid flow are reduced to a nondimensional form, which are then characterized by four dimensionless parameters. With an aim to validate our numerical approach, the computational results are compared with those of the analytical solution available in the developed region far from the singularity. The hydraulic impedance by unit length within the developed flow region increases with the magnetic field. The time average entrance length with a greater precision on the unsteady case decreases with increasing magnetic field strength. The overall voltage characteristics do not depend on the developed flow field within the entry region.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Wajdi Alghamdi ◽  
Abdelaziz Alsubie ◽  
Poom Kumam ◽  
Anwar Saeed ◽  
Taza Gul

AbstractThe current study focuses on the laminar flow of copper and copper oxide ($${\text{Cu/blood}}$$ Cu/blood and $${\text{Cu}} + {\text{CuO/blood}}$$ Cu + CuO/blood ) hybrid nanoliquid, considering blood as a carrier fluid in a rectangular domain between two permeable channels. This study may manipulate for the purpose such as the drug delivery process, flow dynamic mechanism of the micro-circulatory system. In the proposed model, MHD and heat source/sink on the flow pattern have been studied. Furthermore, the sides of each channel are permeable, allowing the nanoliquid to escape, filter, squeezing and dilating with a fixed velocity. Appropriate transformations are incorporated to convert the governing partial differential equations and the boundary conditions suitable for computation. The elegant homotopy analysis method (HAM) is used to obtain analytic approximations for the resulting system of nonlinear differential equations. The features of flow characteristics such as velocity, and temperature profiles in response to the variations of the emerging parameters are simulated and examined with a physical explanation. The magnetic field plays a vital role in the blood flow and therefore the existing literature has been extending with the addition of magnetic field. Among the many outputs of the study, it is found that the pressure distribution decline with the accumulated values of the magnetic parameter at the center of the flow regime. The augmentation in the temperature distribution estimates the pH values and electric conductivity. Therefore, the $${\text{Cu}}\,\,{\text{and}}\,\,{\text{CuO}}$$ Cu and CuO hybrid nanofluids are used in this study for medication purposes. The magnetic field has an important role in the blood flow and therefore the extending study has been extending using the magnetic field. The heat emission/absorption term is added to the energy equation to maintain the homogeneous temperature for the blood flow. We expect that this work will provide efficient outputs for medical purposes such as drug delivery.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2147
Author(s):  
Roman Verkhovskii ◽  
Alexey Ermakov ◽  
Olga Sindeeva ◽  
Ekaterina Prikhozhdenko ◽  
Anastasiia Kozlova ◽  
...  

Drug carriers based on polyelectrolyte microcapsules remotely controlled with an external magnetic field are a promising drug delivery system. However, the influence of capsule parameters on microcapsules’ behavior in vivo is still ambiguous and requires additional study. Here, we discuss how the processes occurring in the blood flow influence the circulation time of magnetic polyelectrolyte microcapsules in mouse blood after injection into the blood circulatory system and their interaction with different blood components, such as WBCs and RBCs. The investigation of microcapsules ranging in diameter 1–5.5 μm allowed us to reveal the dynamics of their filtration by vital organs, cytotoxicity, and hemotoxicity, which is dependent on their size, alongside the efficiency of their interaction with the magnetic field. Our results show that small capsules have a long circulation time and do not affect blood cells. In contrast, the injection of large 5.5 μm microcapsules leads to fast filtration from the blood flow, induces the inhibition of macrophage cell line proliferation after 48 h, and causes an increase in hemolysis, depending on the carrier concentration. The obtained results reveal the possible directions of fine-tuning microcapsule parameters, maximizing capsule payload without the side effects for the blood flow or the blood cells.


2013 ◽  
Vol 4 (2) ◽  
pp. 215-226
Author(s):  
Sarfraz Ahmed

The flow of blood in human circulatory system can be controlled by applying appropriate magnetic field. It is also well known that non-Newtonian nature of blood significantly influences the flows, particularly in the cases where blood vessels are curved, branching or narrow etc. Stenosis refers to localized narrowing of an artery and is a frequent result of arterial disease and is caused mainly due to intravascular atherosclerotic plaque which develops at the arterial wall and protrudes into the lumen of the vessel. Such constrictions disturb normal blood flow through the artery. Here study is made on the flow of blood through a stenosed artery with the effect of slip at the boundary in presence of transverse magnetic field considering blood as Casson fluid (non- Newtonian fluid). The equations of motion has have been solved numerically. The effect of various parameters on the flow characteristics like Hartmann number, Reynolds number has been discussed. Numerical results were obtained for different values of the Hartmann number M and Reynolds number Re. It is observed that the fluid velocity decreases as the Hartmann number increases.


1984 ◽  
Vol 3 (1) ◽  
pp. 293-298
Author(s):  
Isaac Chen ◽  
Subrata Saha
Keyword(s):  

Author(s):  
C. Umadevi ◽  
G. Harpriya ◽  
M. Dhange ◽  
G. Nageswari

The flow of blood mixed with copper nanoparticles in an overlapping stenosed artery is reported in the presence of a magnetic field. The presence of stenosis is known to impede blood flow and to be the cause of different cardiac diseases. The governing nonlinear equations are rendered dimensionless and attempted under the conditions of mild stenosis. The analytical solutions for velocity, resistance to the flow, wall shear stress, temperature, and streamlines are obtained and analyzed through graphs. The obtained outcomes show that the temperature variation in copper nanoparticles concentrated blood is more and flow resistance is less when compared to pure blood. The investigations reveal that copper nanoparticles are effective to reduce the hemodynamics of stenosis and could be helpful in biomedical applications.


2020 ◽  
pp. 53-59
Author(s):  
N. O. Shushliapina ◽  
O. Ye. Cherniakova

The investigation of the vascular microcirculation system is important for diagnosis, assessment of the severity and nature of pathological processes in human body, monitoring the effectiveness of treatment. Monitoring the state of microcirculation in impaired respiratory function of the nose helps to study the subtle mechanisms of regulation of vascular−tissue relations. To do this, there were used the biomicroscopic methods to study capillary blood flow, one of the most relevant and promising is optical capillaroscopy of the nail bed. This method makes it possible to identify at the evidence level the peculiarities of the functioning of the peripheral circulatory system by the state of the capillary system and to evaluate the effectiveness of treatment by the rheological properties of blood in hematological practice. There were examined 145 patients by means of computer capillaroscopy to study the rate of capillary circulation in the patients with pathology of intranasal structures and nasal breathing disorders. All patients underwent a complete clinical examination, routine instrumental examinations, and computer capillaroscopy using a video capillaroscope with a visual magnification of up to 550 times. The obtained images were stored and processed according to a special software. During the characterization of the capillaroscopic picture there were evaluated: pathological tortuosity, change in the caliber of arterioles and venules, disorganization of the capillary network, the number of functioning capillaries. Changes in the speed and nature of capillary blood flow (accelerated, slow, stasis) were observed. The optical capillaroscopy method allows not only to visually assess the condition of microvessels, but also to determine such an important parameter as blood circulation, actually, it can replace the study of laser Doppler. Such data will be important in the diagnosis of respiratory and olfactory disorders and the formation of adequate tactics for their treatment. Key words: microcirculation, microcirculatory tract, capillary circulation, nasal obstruction, nasal breathing disorders, pathology of intranasal structures, computer capillaroscopy.


2020 ◽  
Vol 98 (2) ◽  
pp. 172-182 ◽  
Author(s):  
Kaleem Ullah ◽  
Nasir Ali

This paper investigates the streamline topologies and stability of stagnation points and their bifurcations for an asymmetric peristaltic flow. The asymmetry of channel is due to the propagation of peristaltic waves with different phases and amplitudes on the flexible channel walls. An exact analytic solution of the flow problem subject to the constraints of low Reynolds number and long wavelength is obtained in wave frame of reference moving with wave velocity. A system of nonlinear differential equations is established to locate and classify the stagnation points in the flow domain. Different flow situations, manifested in the flow field, are categorized as: backward flow, trapping, and augmented flow. The transition from one situation to the other corresponds to bifurcation, which is explored graphically through local and global bifurcation diagrams. This analysis discloses the stability status of stagnation points and ranges of involved parameters in which various flow conditions appear in the flow field. It is concluded that the trapping in an asymmetric peristaltic transport can be reduced by increasing the phase difference of the channel walls. It is also found that the augmented flow region shrinks and the trapping region expands by increasing the amplitude ratio of the channel walls.


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