Thermal, microrotation, electromagnetic field and nanoparticle shape effects on Cu-CuO/blood flow in microvascular vessels.

A thermal analysis of Cu-CuO/ blood nanofluids flow in asymmetric microchannel propagating with wave velocity is presented in this study. For the blood, a micropolar fluid model is considered to investigate the microrotation effects of blood flow. Thermal radiation effects and the influence of nanoparticle shape, electric double layer thickness, and electromagnetic fields on the flow are studied. Three types of nanoparticles shapes namely cylinder, bricks and platelets are taken into account. Governing equations are solved under the approximations of long wavelength, low Reynolds number, and Debye-Hückel linearization. Numerical computations are performed for the axial pressure gradient, axial velocity, spin velocity and temperature distribution. The effects of various physical parameters on flow and thermal characteristics are computed and their physical interpretation is also discussed. The outcomes indicate that the axial velocity of Cu-CuO/blood nanoparticles strongly depends on applied electromagnetic field and microrotation. The model's finding will be applicable in designing the smart electromagnetic micro pumps for the hemodialysis and lungs-on-chip devices for the pumping of the blood.

Unsteady micropolar nanofluid flow past a variable riga stretchable surface with variable thermal conductivity.

In this study, we considered the flow of a micropolar fluid over a vertical Riga sheet. The non linear stretching sheet is considered. The effects of variable thermal conductivity and radiation on the Riga sheet are taken into account. Additionally, we also debated the Brownian motion and thermophoretic. To simplify the partial differential equations, we converted them into dimensionless ordinary differential equations using suitable similarity variables and solved dimensionless system numerically using the bvp4c function. The impact of some intended parameters on the dimensionless velocity, microrotation, temperature, and concentration distributions graphically are presented and the numerical outcomes of physical quantities like skin friction, Nusselt number, Sherwood number, and couple stress have been presented in tabular form. The micropolar parameter increased which increased the couple stress and friction at surface. Because, the fluid rotation increased which increased friction at surface and also increased the couple stress. The transfer of mass decayed and transfer of heat heightened by larger values of variable thermal conductivity. Thermal conductivity improved which improved the heat transfer phenomena, so transfer of heat at surface becomes larger while also reducing the transfer of mass.

Cross-diffusive flow of MHD micropolar nanofluid past a slip stretching plate.

As a novel fluid of functional material, magnetohydrodynamic (MHD) micropolar fluid has the special properties of light, heat, magnetic and so on. It is of highly practical significance. The characteristics of flow, heat and mass transfer in MHD micropolar nanofluid boundary layer past a stretching plate are investigated based on the micropolar fluid theory in the present numerical work. In the presence of magnetic field, viscous dissipation and the cross-diffusion caused by Dufour effect and Soret effect are considered. First order slip velocity condition is employed. Mathematical models are built based on the assumptions. Collocation spectral method (CSM) via matrix multiplication is adopted to solve the two-dimensional dimensionless nonlinear partial governing equations. The program codes based on CSM is developed, validated and employed. The coupled effects of microrotation, Dufour effect, Soret effect, magnetic field as well as first order slip velocity boundary condition on the flow, heat and mass transfer are revealed. Besides, the variation trends of local Nusselt number and Sherwood number are analyzed in detail. The numerical results indicate that the fluid flow can be suppressed obviously in the consideration n of slip condition and magnetic field. As slip parameter δ and magnetic parameter M rise, the velocity in the boundary layer becomes lower gradually; further, both temperature and concentration increase. On the other hand, the opposite trend can be noticed with the effect of material parameter K. Moreover, Ec and Df augment the temperature; while, Sr leads to an upsurge in concentration. The temperature rises by about 79.73% with Dufour effect and Sh enlarges by a factor of about 38.15% with Soret effect. The concentration boundary layer decreases by about 37.50% is when K=5.0.

Mathematical analysis of nonlinear thermal radiation and nanoparticle aggregation on unsteady MHD flow of micropolar nanofluid over shrinking sheet.

Significance of study: Typical liquids aren't great for engineering because of their low heat conductivity. To enhance heat transfer capabilities in industries as diverse as computers, pharmaceuticals, and molten metals, researchers and scientists have developed nanofluids, which are composed of nanoparticles distributed in a base fluid. Aim of study: Mathematical modeling of micropolar C u - H 2 O nanofluid driven by a deformable sheet in the stagnation area with nanoparticle aggregation, thermal radiation, and the mass suction action has been investigated in this paper. In this case, copper ( C u ) nanoparticles make up the nanofluid. Method: ology: We have used suitable transformations to arrive at a system of nonlinear ODEs, which we then solve numerically in MATHEMATICA using Runge-Kutta methods of the fourth order coupled with shooting approaches. Findings: Tables and graphs are used to examine the effects of immersed flow and display profiles of physical parameters of interest. This includes velocities, temperatures, skin friction, and Nusselt numbers. The average heat transfer rate increased to 17 . 725 % as the volume percentage of copper nanoparticles in micropolar nanofluid increased from 0.0 to 0.01 . Additionally, the results showed that the local Nusselt number of the micropolar nanofluid increased along with an increase in the unsteady and radiation parameters. However, its value is reduced in an undeniable fashion if a material parameter is present. The impact of radiation on the aggregation of nanoparticles is compared and contrasted with the effects of a non-radiative scenario, and the resulting fluctuations in Nusselt numbers are provided in tables. When the results of this study were compared to data that had already been published about some cases, a lot of agreement was found.

Nanoparticle Aggregation and Thermophoretic Particle Deposition Process in the Flow of Micropolar Nanofluid over a Stretching Sheet.

The purpose of this research is to investigate the consequence of thermophoretic particle deposition (TPD) on the movement of a TiO2/water-based micropolar nanoliquid surface in the existence of a porous medium, a heat source/sink, and bioconvection. Movement, temperature, and mass transfer measurements are also performed in the attendance and nonappearance of nanoparticle aggregation. The nonlinear partial differential equations are transformed into a system of ordinary differential equations using appropriate similarity factors, and numerical research is carried out using the Runge-Kutta-Felhberg 4th/5th order and shooting technique. The obtained results show that improved values of the porous constraint will decline the velocity profile. Improvement in heat source/sink parameter directly affects the temperature profile. Thermophoretic parameter, bioconvection Peclet number, and Lewis number decrease the concentration and bioconvection profiles. Increases in the heat source/sink constraint and solid volume fraction will advance the rate of thermal dispersion. Nanoparticle with aggregation exhibits less impact in case of velocity profile, but shows a greater impact on temperature, concentration, and bioconvection profiles.

Irreversibility analysis of an unsteady micropolar CNT-blood nanofluid flow through a squeezing channel with activation energy-Application in drug delivery.

BACKGROUND AND OBJECTIVE: Due to the low toxicity, unique physiochemical properties, and appropriate surface modifications, Carbon Nanotubes (CNTs) are used as target carriers in drug delivery systems. In the present problem, we have considered both single-walled and multi-walled CNTs to study the impact of irreversibility on the micropolar nanofluid flow through a squeezing channel with the base fluid blood. The blood is considered a micropolar fluid in the presence of different blood cells and their rotational nature. Further, blood is influenced by the external magnetic field parallel to the microrotation along with viscous and Joule dissipations. METHOD: Highly coupled and nonlinear partial differential equations are solved with Homotopy Analysis Method (HAM) after simplified equations using similarity transformation. Further, we have concluded the minimum squared residual errors to show the method's accuracy. A comparison made with the existing literature and shows a good agreement. RESULTS: The angular velocity of the fluid particles is enhanced by increasing the squeezing number. In the case of the squeezing, volume fraction has improved the viscous drag and is found high for MWCNT embedded nanofluid. The heat transfer rate is higher for the MWCNT embedded nanofluid than the SWCNT embedded nanofluid. A descent found in entropy generation boosts up with the Brinkman parameter while opposite phenomena appear for radiation and Hartman number and vortex viscosity. Both Bejan number and entropy generation profiles are restricted with an increase in vortex viscosity. CONCLUSION: SWCNTs are showed to be more effective and efficient than the MWCNTs in elevating velocity, temperature and irreversibility of the system. Outcomes of this problem will help to understand the implementation of the drug carrier and irreversibility phenomena during drug delivery.

Flow investigation of second grade micropolar nanofluid with porous medium over an exponentially stretching sheet.

This article mainly focuses on the influence of heat and mass transportation of micropolar second grade nanofluid toward porous medium of an exponentially stretched surface. The significance of activation energy and viscous dissipation with magnetic effect are taken into deliberated. Furthermore, to analyze the heat and mass transport scrutiny the concentration and thermal slip boundary conditions are assessed on the surface of the sheet. The convenient similarity variables are adopted to transfer the non-linear governing PDEs into the dimensionless ODEs and their corresponding boundary conditions also transformed. The nonlinear coupled ODEs are numerically solved by the usage of BVP4C MATLAB technique. The obtained numerical estimations are displayed graphically to display the significance of the various parameters against the velocity, temperature, microrotation, concentration distributions. It is noticed that larger estimations of micropolar and second grade parameter improves the fluid velocity consequently, while opposite trend is found for the higher estimation of porous medium parameter. Further, it is observed that the skin friction rate is boosted by the increment of ε and ß, whereas opposite trend is noted against the mass transfer rate and heat transfer rate.

Numerical analysis of water based CNTs flow of micropolar fluid through rotating frame.

BACKGROUND: In this article, the nanomaterial flow of micropolar fluid in rotating frame is considered. The SWCNT and MWCNT with base fluid namely pure water is also taken into account to analyze the flow behavior over stretching surface. Mathematical model have been constructed under the nanomaterial of micropolar fluid. METHOD: The governing equations have been developed in the form of system of partial differential equations. The partial differential equations are transformed into ordinary differential equations using similarity transformations. The transformed system has been solved through MAPLE software. RESULTS: The physical parameters like as thermal slip effects, velocity slip effects and magnetic hydrodynamics on the micropolar nanofluid are presented by tables and graphs. Surprisingly in the rotating parameter, F''(0) and - θ'(0) increases for higher values of the rotating parameter while opposite to be noted for G''(0). The Nusselt number and skin friction increases for higher values of micropolar parameter but MWCNT achieves higher heat transfer as associated to SWCNT.

Mathematical analysis of magnetohydrodynamic (MHD) flow of micropolar nanofluid under buoyancy effects past a vertical shrinking surface: dual solutions.

In this paper, we explore dual solutions of MHD flow, heat and mass transfer of micropolar nanofluid over a linear vertical shrinking surface with buoyancy effects, which was not considered in the previous works. The governing fluid flow equations of this problem are transformed into nonlinear boundary value problems (BVPs) of ordinary differential equations (ODEs) by applying similarity variables. The resultant BVPs are converted into initial value problems (IVPs) by using shooting method which then resolved by employing Runge Kutta of order four. The impacts of the governing parameters, such as suction parameter, material parameter, Richardson number, magnetic parameter, Prandtl number, thermophoresis and Brownian motion parameters on velocity, angular velocity, temperature, and concentration are illustrated graphically. The results indicate that the existence of a range of dual solutions and no-solutions. When Richardson number ( δ ) is increased, the reduction of the velocity of micropolar nanofluid has occurred in the second solution. The stability analysis on dual solutions, however, reveals that only the first solution is stable.