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1.
Sci Rep ; 14(1): 1474, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233420

RESUMEN

The current investigation examines the peristaltic flow, in curved conduit, having complaint boundaries for nanofluid. The effects of curvature are taken into account when developing the governing equations for the nano fluid model for curved channels. Nonlinear & coupled differential equations are then simplified by incorporating the long wavelength assumption along with smaller Reynolds number. The homotopy perturbation approach is used to analytically solve the reduced coupled differential equations. The entropy generation can be estimated through examining the contributions of heat and fluid viscosities. The results of velocity, temperature, concentration, entropy number, and stream functions have been plotted graphically in order to discuss the physical attributes of the essential quantities. Increase in fluid velocity within the curved conduit is noticed for higher values of thermophoresis parameter and Brownian motion parameter further entropy generation number is boosted by increasing values of Grashof number.

2.
Sci Rep ; 14(1): 1475, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233426

RESUMEN

The magnetic force effects and differently shaped nano-particles in diverging tapering arteries having stenoses are being studied in current research via blood flow model. There hasn't been any research done on using metallic nanoparticles of different shapes with water as the base fluid. A radially symmetric but axially non-symmetric stenosis is used to depict the blood flow. Another significant aspect of our research is the study of symmetrical distribution of wall shearing stresses in connection with resistive impedance, as well as the rise of these quantities with the progression of stenosis. Shaping nanoparticles in accordance with the understanding of blood flow in arteries offers numerous possibilities for improving drug delivery, targeted therapies, and diagnostic imaging in the context of cardiovascular and other vascular-related diseases. Exact solutions for different flow quantities namely velocity, temperature, resistance impedance, boundary shear stress, and shearing stress at the stenosis throat, have been assessed. For various parameters of relevance for Cu-water, the graphical results of several types of tapered arteries (i.e. diverging tapering) have been explored.


Asunto(s)
Arterias , Nanopartículas , Humanos , Constricción Patológica , Arterias/fisiología , Hemodinámica , Agua , Modelos Cardiovasculares , Velocidad del Flujo Sanguíneo , Simulación por Computador , Estrés Mecánico
3.
Sci Rep ; 14(1): 518, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38177658

RESUMEN

A novel mathematical analysis is established that summits the key features of peristaltic propulsion for a non-Newtonian micropolar fluid with the electroosmosis and heat transfer enhancement using nanoparticles. In such physiological models, the channel have a symmetric configuration in accordance with the biological problem. Being mindful of this fact, we have disclosed an integrated analysis on symmetric channel that incorporates major physiological applications. The creeping flow inference is reviewed to model this realistic problem. Flow equations are model using cartesian coordinates and simplified using long wave length and low Reynolds number approximation. Nonlinear linear couple equations are solving numerically. We have studied the variation in the properties of nanofluid developed by two different types of nanoparticles (i.e. Cu and Ag nanoparticles). Graphical illustrations are unveiled to highlight the physical aspects of nanoparticles and flow parameters. The exploration demonstrates that the micro-rotation of the nano-liquid elements enhances the thermal conductivity of the fluid movement. The effect of micropolar fluid parameters on mean flow and pressure variables is also presented.

4.
Sci Rep ; 13(1): 21891, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38082095

RESUMEN

In the present article we consider the physical model of two-dimensional Casson hybrid nanofluids flow, which is magnetized and thermally radiative, laminar, incompressible inside the channel. Flow equations have been modelled for two dimensional axial and radial velocity components [Formula: see text] along [Formula: see text] and [Formula: see text] along the [Formula: see text]. There exists temperature [Formula: see text] which is constant for upper and lower walls. The Casson nanofluids model with nano type particles includes heat transfer effect between two stretched and shrinking walls of the channel was constructed. The continuity, momentum and energy equations are modelled in cartesian coordinates system. The finite element technique is used to evaluate numerical solutions for velocity, temperature, Skin friction and Nusselt number. It is evident that the hybrid Casson nanofluids exhibit opposite behaviors in the stretching and shrinking cases near the upper and lower walls of the channel. It is also observed that in the stretching case, increasing the values of the Casson parameter leads to a rise in both shear stress and heat transfer rate for both plates of the channel. However, the results contradict this trend in the shrinking case. Understanding the thermal characteristics of magnetized hybrid fluids can be applied to the design of advanced cooling systems in engineering applications, biomedical fluid dynamic, in energy system this study can be applied to improve the efficiency of energy systems where fluid flow and heat transfer play crucial roles. Further use of nanofluids suggests a connection to nanotechnology, and the study may have implications for the development of advanced nanomaterial-based heat transfer fluids.

5.
Sci Rep ; 13(1): 18491, 2023 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-37898684

RESUMEN

A novel mathematical analysis is established that summits the key features of Cilia propulsion for a non-Newtonian Couple Stress fluid with the electroosmosis and heat transfer. In such physiological models, the conduit may have a symmetric or asymmetric configuration in accordance with the biological problem. Being mindful of this fact, we have disclosed an integrated analysis on symmetric in addition to asymmetric conduits that incorporates major physiological applications. The creeping flow inference is reviewed to model this realistic problem and exact solutions are computed for both the conduit cases. Graphical illustrations are unveiled to highlight the physical aspects of cilia propulsion on symmetric in addition to asymmetric conduit and an inclusive comparison study is conveyed. The flow profile attains higher values for an asymmetric conduit in relation to the symmetric. Likewise, the pressure rise and pressure gradient also score high for asymmetric conduit in relation to the symmetric conduit. A visual representation of flow inside symmetric as well as asymmetric conduit is provided by streamline graphs and temperature profile as well.

6.
Sci Rep ; 13(1): 11801, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37479868

RESUMEN

The main focus of this article is to mathematically formulate the microfluidics-based mechanical system for nanofluids. A 50:50 mixture of propylene glycol (PG) and water is used as a heat transfer fluid because of its tremendous anti-freezing properties, and nontoxicity and it is safe to be utilized at the domestic level. Titanium dioxide (titania) nanoparticles are suspended in the working fluid to enhance its heat transfer ability. The fluid flow is induced by electroosmosis in a microtube, which is further assisted by cilia beating. The impacts of Joule heating and non-linear thermal radiation are also considered. The simplification of the dimensionless system is done under lubrication theory and the Debye-Hückel linearization principle. The nonlinear system of equations is executed for a numerical solution by adopting the symbolic mathematical software Maple 17 using the command "dsolve" along with the additional command "numeric" to get the numerical solution. This command utilizes a low-ordered method along with accuracy-enhancing schemes such as the deferred correction technique and Richardson extrapolation to get a numerical answer of desired accuracy, where we can choose the accuracy level and mesh points according to our requirements. The detailed analysis of results obtained from the numerical treatment of the considered problem indicates that the efficiency of the PG + water enhances due to the suspension of the nanoparticles and heat is rapidly removed from the system. Further, the velocity of the fluid is augmented by decreasing the thickness of the electric double layer and raising the strength of the electric field in the forwarding direction.

7.
Heliyon ; 9(5): e15699, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37153439

RESUMEN

The purpose of the current article is to explore the impact of thermal stratification and medium porosity on gravity-coerced transport of hybrid carbon nanotubes down an upright extending sheet inspired by a constant applied magnetic field along with heat transfer investigation in existence of thermal radiation, viscous dispersal, and joule heating effect. Rectangular coordinates are chosen for the mathematical interpretation of the governing flow problem. Homothetic analysis is employed for the sake of simplification process. The reduced system of coupled nonlinear differential equations is dealt numerically by dint of computational software MATLAB inbuilt routine function Bvp4c. The numerical investigation is carried out for the distinct scenarios namely, ( i ) Presence of favorable buoyancy force, ( i i ) Case of purely forced convection and ( i i i ) Presence of opposing buoyancy force. Significant Findings: The key findings include that the presence of hybrid carbon nanotubes and medium porosity contributes significantly to upsurging surface shear stress magnitude whereas, external magnetic field and velocity slip effects in an altered manner. The present study may be a benchmark in study of fueling process in space vehicles and space technology.

8.
Sci Rep ; 13(1): 3231, 2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36828864

RESUMEN

This article is mainly focused on the viscous flow of cu-water/Methanol suspended nanofluids towards a three-dimensional stretching sheet reformed by magnetohydrodynamic phenomenon. The viscous effect is considered as temperature dependent with water treated as a base fluid. Similarity conversions are employed to set forth the non-linear equations of this physical problem. An innovative model for 3D analysis for cu-water/Methanol nanofluid with an irregular viscosity is presented in the present study. Reynold's model of viscosity is considered in the present study. Moreover, shooting technique is employed to elaborate the non-linear coupled governing equations with the relevant boundary conditions. The physical interpretation of these numerical calculations is presented through a graphical specimen of velocity, Nusselt number, temperature, and skin friction etc. The results of present model are showing quality harmony with the results of existing model. This model is being used for manipulating and designing the surfaces such as stretching/shrinking wrapping and panting devices in nanotechnology. The results also show the significant changes in flow characteristics with changing the value of stretching parameter. It is observed that with an increasing in nanoparticles volume fraction boundary layer thickness decreases. Further, it is also observed that with an increase in viscosity parameter, temperature increases because here we are considering temperature dependent viscosity.

10.
Microvasc Res ; 145: 104435, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36115732

RESUMEN

Pumping devices with the electrokinetics phenomena are important in many microscale transport phenomena in physiology. This study presents a theoretical and numerical investigation on the peristaltic pumping of non-Newtonian Sutterby nanofluid through capillary in presence of electromagnetohydrodynamics. Here blood (Sutterby fluid) is taken as a base fluid and nanofluid is prepared by the suspension of graphene oxide nanoparticles in blood. Graphene oxide is extremely useful in the medical domain for drug delivery and cancer treatment. The modified Buongiorno model for nanofluids and Poisson-Boltzmann ionic distribution is adopted for the formulation of the present problem. Constitutive flow equations are linearized by the implementation of approximations of low Reynolds number, large wavelength, and the Debye-Hückel linearization. The numerical solution of reduced coupled and nonlinear set of equations is computed through Mathematica and graphical illustration is presented. Further, the impacts of buoyancy forces, thermal radiation, and mixed convection are also studied. It is revealed in this investigation that the inclusion of a large number of nanoparticles alters the flow characteristics significantly and boosts the heat transfer mechanism. Moreover, the pumping power of the peristaltic pump can be enhanced by the reduction in the width of the electric double layer which can be done by altering the electrolyte concentration.

11.
Front Chem ; 10: 1021303, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36304747

RESUMEN

We analyze the steady laminar incompressible boundary-layer magnetohydrodynamic impacts on the nanofluidic flux over a static and mobile wedge in the existence of an applied magnetic field. The Falkner-Skan wedge flow model is taken into consideration. Reynolds' model is considered to introduce temperature-dependent viscosity. As in real life, most fluids have variable viscosity. The executive partial differential equations are converted into a set-up of ordinary differential equations by means of a similarity conversion. Numerical solutions are computed for the converted set-up of equations subjected to physical boundary conditions. The specific flow dynamics like velocity profile, streamlines, temperature behavior, and coefficient of local skin friction are graphically analyzed through numerical solutions. It is concluded that the laminar boundary-layer separation from the static and moving wedge surface is altered by the applied external electric field, and the wedge (static or moving) angle improves the surface heat flux in addition to the coefficient of skin friction. Furthermore, it is found that the methanol-based nanofluid is a less-efficient cooling agent than the water-based nanofluid; therefore, the magnitude of the Nusselt number is smaller for the water-based nanofluid. It is also observed that the addition of only 1% of these nanoparticles in a base fluid results in an enhancement of almost 200% in the thermal conductivity.

12.
Afr Health Sci ; 21(3): 1117-1123, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35222574

RESUMEN

PURPOSE: The interpretation & correlation of the different laboratory parameters in positive dengue cases in order to evaluate that which laboratory test is more significant for diagnosis of Dengue. METHODS: Prospective examination of samples (patients' serum) for dengue virus of different genotype by using multiplex anti-dengue IgM, IgG. We have done NS-1 test by (ICT) immunochromatographic devices, and complete blood picture (CBC) by Sysmex XP-100. RESULT: Detection of Viral RNA in 100 patients showed effects in the total of 73 (73.0%) samples. This graphical comparison shows the whole positive cases including dengue NS-I antigen, dengue serology (IgM & IgG), total 62 positive cases of NS-I are detected, 10 positive cases of dengue IgM and 9 positive cases of IgG detected, in which Complete Blood Test (CBC) shows remarkable reduction in Platelets (32 cases) and Leucopenia in (24 positive cases). CONCLUSION: In this research, it is concluded that the diagnosis of dengue cases is preliminary limited to initial stages i.e. CBC or sometimes dengue NS-I, as dengue IgM severity is more effective than that of Dengue NS-I & IgG. Many patients who had negative results in CBC and NS-1 testing, became positive when IgM and IgG serology testing has been done.


Asunto(s)
Virus del Dengue , Dengue , Anticuerpos Antivirales , Dengue/diagnóstico , Dengue/epidemiología , Brotes de Enfermedades , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Inmunoglobulina G , Inmunoglobulina M , Estudios Prospectivos , Sensibilidad y Especificidad
13.
Microvasc Res ; 132: 104062, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32828761

RESUMEN

Pumping devices with the electrokinetics phenomena are important in many microscale transport phenomena in physiology. This study presents a theoretical and numerical investigation on the peristaltic pumping of non-Newtonian Sutterby nanofluid through capillary in presence of electromagnetohydrodynamics. Here blood (Sutterby fluid) is taken as a base fluid and nanofluid is prepared by the suspension of graphene oxide nanoparticle in blood. Graphene oxide is extremely useful in the medical domain for drug delivery and cancer treatment. The modified Buongiorno model for nanofluids and Poisson-Boltzmann ionic distribution is adopted for the formulation of the present problem. Constitutive flow equations are linearized by the implementation of approximations low Reynolds number, large wavelength, and the Debye-Hückel linearization. The numerical solution of reduced coupled and nonlinear set of equations is computed through Mathematica and graphical illustration is presented. Further, the impacts of buoyancy forces, thermal radiation, and mixed convection are also studied. It is revealed in this investigation that the inclusion of a large number of nanoparticles alters the flow characteristics significantly and boosts the heat transfer mechanism. Moreover, the pumping power of the peristaltic pump can be enhanced by the reduction in the width of the electric double layer which can be done by altering the electrolyte concentration.


Asunto(s)
Capilares/fisiología , Campos Electromagnéticos , Grafito/química , Microcirculación , Modelos Cardiovasculares , Nanopartículas , Flujo Pulsátil , Animales , Velocidad del Flujo Sanguíneo , Simulación por Computador , Humanos , Análisis Numérico Asistido por Computador , Factores de Tiempo
14.
Biomech Model Mechanobiol ; 19(5): 1925-1933, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32125543

RESUMEN

In the present investigation, we have studied the effects of heat transfer on the peristaltic flow considering the Phan-Thien-Tanner fluid model. The fluid is flowing in a uniform circular tube in the form of wave motion. The inner walls of the tube are considered to be ciliated with small hair-like structures. Exact solutions have been derived for velocity, temperature and pressure gradient. Mechanical properties of the fluid, such as velocity, temperature, pressure rise and pressure gradient, have been discussed graphically. Trapping phenomena due to the variation of physical parameters have been deliberated. It has been observed that when the viscous forces are greater than the elastic forces, the velocity of the fluid flow significantly decreases, thermal conductivity of the fluid improves and the pressure gradient along the tube increases.


Asunto(s)
Cilios/fisiología , Calor , Modelos Biológicos , Peristaltismo , Reología , Presión
15.
Comput Methods Programs Biomed ; 146: 1-9, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28688478

RESUMEN

BACKGROUND AND OBJECTIVES: This paper aims to investigate the unsteady flow of two types of nanofluids i.e Copper water nanofluids and Silver water nanofluids) through finite length non-uniform channel driven by peristaltic sinusoidal wave propagations. METHODS: The governing equations are reduced in linear form using dimensional analysis and considering the low Reynolds number and large wavelength approximations. The time dependent temperature field, axial velocity, transverse velocity and pressure difference are obtained analytically in closed form solution. Trapping phenomenon is also discussed with the help of contour plots of stream function. A comparative study of pure water (Newtonian fluid), Copper water nanofluids and Silver water nanofluids under the influence of relevant physical parameters is made in graphical form and also discussed. The effects of absorption parameter and Grashof number on velocity profiles, temperature profiles and pressure distribution along the length of channel are examined. RESULTS CONCLUSIONS: The computational results reveal that the velocity profile is maximum for Silver water nanofluids however, it is least for Copper water nanofluids. It is also concluded the temperature profile is more for pure water in comparison to Silver water and Copper water nanofluids. This model is applicable to design, micro-peristaltic pumps which help in Nanoparticle-based targeted drug delivery and to transport the sensitive or corrosive fluids, sanitary fluids, slurries and noxious fluids in nuclear industry.


Asunto(s)
Cobre/análisis , Nanoestructuras/análisis , Reología , Plata/análisis , Agua/análisis , Presión
16.
Comput Methods Programs Biomed ; 136: 21-9, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27686700

RESUMEN

BACKGROUND AND OBJECTIVES: With ongoing interest in CNT nanofluids and materials in biotechnology, energy and environment, microelectronics, composite materials etc., the current investigation is carried out to analyze the effects of variable viscosity and thermal conductivity of CNT nanofluids flow driven by cilia induced movement through a circular cylindrical tube. Metachronal wave is generated by the beating of cilia and mathematically modeled as elliptical wave propagation by Blake (1971). METHODS, RESULTS AND CONCLUSIONS: The problem is formulated in the form of nonlinear partial differential equations, which are simplified by using the dimensional analysis to avoid the complicacy of dimensional homogeneity. Lubrication theory is employed to linearize the governing equations and it is also physically appropriate for cilia movement. Analytical solutions for velocity, temperature and pressure gradient and stream function are obtained. The analytical results are numerically simulated by using the Mathematica Software and plotted the graphs for velocity profile, temperature profile, pressure gradient and stream lines for better discussion and visualization. This model is applicable in physiological transport phenomena to explore the nanotechnology in engineering the artificial cilia and ciliated tube/pipe.


Asunto(s)
Nanotecnología , Conductividad Térmica , Biotecnología , Calor , Modelos Teóricos
17.
Comput Methods Programs Biomed ; 134: 43-51, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27480731

RESUMEN

BACKGROUND AND OBJECTIVES: The present investigation is associated with the contemporary study of viscous flow in a vertical tube with ciliary motion. METHODS/RESULTS/CONCLUSIONS: The main flow problem has been modeled using cylindrical coordinates; flow equations are simplified to ordinary differential equations using longwave length and low Reynold's number approximation; and exact solutions have been obtained for velocity, pressure gradient and temperature. Results acquired are discussed graphically for better understanding. Streamlines for the velocity profile are plotted to discuss the trapping phenomenon. It is seen that with an increment in the Grashof number, the velocity of the governing fluids starts to decrease significantly.


Asunto(s)
Cilios/fisiología , Nanopartículas del Metal/química , Modelos Teóricos , Gráficos por Computador
18.
Comput Methods Programs Biomed ; 132: 45-55, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27282226

RESUMEN

BACKGROUND AND OBJECTIVES: In the present article, I have studied the blood flow of a Walter's B fluid through a tapered artery with a stenosis. The problem is modeled in cylindrical coordinates system. METHODS RESULTS CONCLUSIONS: The analytical solutions have been carried out using regular perturbation method by taking α as perturbation parameter. The expressions for velocity, resistance impedance, wall shear stress and shearing stress at the stenosis throat have been evaluated. The graphical results of different types of tapered arteries (i.e. converging tapering, diverging tapering, non-tapered artery) have been examined for different parameters of interest.


Asunto(s)
Arterias/fisiología , Modelos Teóricos , Flujo Sanguíneo Regional
19.
Comput Methods Programs Biomed ; 130: 22-30, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27208518

RESUMEN

The peristaltic flow of a copper oxide water fluid investigates the effects of heat generation and magnetic field in permeable tube is studied. The mathematical formulation is presented, the resulting equations are solved exactly. The obtained expressions for pressure gradient, pressure rise, temperature, velocity profile are described through graphs for various pertinent parameters. It is found that pressure gradient is reduce with enhancement of particle concentration and velocity profile is upturn, beside it is observed that temperature increases as more volume fraction of copper oxide. The streamlines are drawn for some physical quantities to discuss the trapping phenomenon.


Asunto(s)
Cobre/química , Nanopartículas/química , Agua/química , Calor
20.
Proc Inst Mech Eng H ; 230(9): 817-828, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30213252

RESUMEN

The human intestinal tract is a long, curved tube constituting the final section of the digestive system in which nutrients and water are mostly absorbed. Motivated by the dynamics of chyme in the intestine, a mathematical model is developed to simulate the associated transport phenomena via peristaltic transport. Rheology of chyme is modelled using the Nakamura-Sawada bi-viscosity non-Newtonian formulation. The intestinal tract is considered as a curved tube geometric model. Low Reynolds number (creeping hydrodynamics) and long wavelength approximations are taken into consideration. Analytical solutions of the moving boundary value problem are derived for velocity field, pressure gradient and pressure rise. Streamline flow visualization is achieved with Mathematica symbolic software. Peristaltic pumping phenomenon and trapping of the bolus are also examined. The influence of curvature parameter, apparent viscosity coefficient (rheological parameter) and volumetric flow rate on flow characteristics is described. Validation of analytical solutions is achieved with a MAPLE17 numerical quadrature algorithm. The work is relevant to improving understanding of gastric hydrodynamics and provides a benchmark for further computational fluid dynamic simulations.

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