Numerical simulation of hydrothermal features of Cu-H2O nanofluid natural convection within a porous annulus considering diverse configurations of heater

The purpose of the current study is to numerically investigate the effects of shape factors of nanoparticles on natural convection in a fluid-saturated porous annulus developed between the elliptical cylinder and square enclosure. A numerical method called the control volume-based finite element method is implemented for solving the governing equations. The modified flow and thermal structures and corresponding heat transfer features are investigated. Numerical outcomes reveal very good grid independency and excellent agreement with the existing studies. The obtained results convey that at a certain aspect ratio, an increment in Rayleigh and Darcy numbers significantly augments the heat transfer and average Nusselt number. Further, enhancement of Rayleigh number increases the velocity of nanofluid, while that of aspect ratio of the elliptical cylinder shows the opposite trend

Investigation of heat transfer for cooling turbine disks with a non-Newtonian fluid flow using DRA

A non-Newtonian viscoelastic fluid flow passes through the porous wall of an axisymmetric channel on a turbine disc for cooling application. The present article solves the couple equations (momentum and heat transfer) of a non-Newtonian fluid flow in an axisymmetric channel with a porous wall for turbine cooling applications by using the Duan–Rach Approach (DRA). The precious achievement of the present work is introducing a new and efficient approximate analytical technique that this method allows us to find a solution without using numerical methods to evaluate the undetermined coefficients. The approximate analytical investigation is carried out for different values of the embedding parameters namely: Reynolds number, Prandtl number, injection Reynolds number and power law index. The DRA results indicate that Nusselt number has direct relationship with Reynolds number, Prandtl number and power law index. Also the results were compared with numerical solution in order to verify the accuracy of the proposed method. It is seen that the current results in comparison with the numerical ones are in excellent agreement

Micropolar nanofluid flow and heat transfer between penetrable walls in the presence of thermal radiation and magnetic field

Flow and heat transfer of MHD micro-polar nanofluid in a channel with penetrable walls and considering thermal radiation impact are investigated. A similarity transformation is utilized to transmute the governing momentum and energy equations into non-linear ordinary differential equations with the appropriate boundary conditions. The gained non-linear ordinary differential equations are solved by Duan–Rach Approach (DRA). This method allows us to detect a solution without applying numerical methods to evaluate the unspecified coefficients. The impacts of diverse active parameters such as the micro-polar parameter, the magnetic parameter, the volume fraction of nanofluid and the radiation parameter on the velocity and temperature profiles are examined. Furthermore, the value of the Nusselt number is calculated and presented through figures. Keywords: Micro-polar nanofluid, Penetrable channel, MHD, Thermal radiation, Duan-Rach Approach (DRA

Magnetohydrodynamic Nanofluid Natural Convection in a Cavity under Thermal Radiation and Shape Factor of Nanoparticles Impacts: A Numerical Study Using CVFEM

In this study, the natural convection of a magnetohydrodynamic nanofluid in an enclosure under the effects of thermal radiation and the shape factor of nanoparticles was analyzed numerically using the control-volume-based finite element method (CVFEM). Columns, spheres, and lamina are examples of the nanoparticle shapes used in the investigation. The study of nanofluid flow and heat transfer was accomplished with an extensive range of nanofluid volume fractions, radiation parameters, Hartmann numbers, Rayleigh numbers, and nanoparticle shape factors. Also, the correlation between the average Nusselt number and the influencing parameters of the current study was determined. The findings demonstrate that laminar nanoparticles have a more notable impact on the average and local Nusselt numbers than the other nanoparticle shapes

Hydrothermal and entropy production analyses of magneto-cross nanoliquid under rectified Fourier viewpoint: A robust approach to industrial applications

The present article has been groomed to explore the boundary-driven magnetized flow of cross nanoliquid over thin needle subject to auto catalysis chemical reactions. In addition to it, the effect of entropy optimization model is incorporated and transportation of heat under non-uniform heat source/sink, Cattaneo-Christov heat flux (rectified Fourier) viewpoint (CCHF), and non-linear thermal radiation is also taken into account. Furthermore, the Brownian and thermophoresis aspects of nanoliquid are invoked. The dimensionless governing equations are solved by apposite shooting scheme. The outcomes of the present study via demonstrated graphs and numerical benchmarks seem to indicate that controlled Sakiadis and Blausius flow pattern of cross nanofluids is attained due to incremented magnetic field strength. Temperature ratio parameter contributes the upgradation of thermal boundary layer thickness and homogenous reaction rate leads to the diminution of nanoparticles concentration. The relative values of needle velocity and the velocity of cross nanofluid are most important factor for the regulation of viscous drag force and rate of heat transportation. Augmented Weissenberg parameter and Reynolds number are the prime factor for the uplift of the flow field and the related layer thickness. Furthermore, the existence of CCHF could result in augmentation in Nusselt

Ternary hybrid nanofluid natural convection within a porous prismatic enclosure with two movable hot baffles: An approach to effective cooling

Natural convection heat transfer in a porous prismatic enclosure emplacing two movable hot baffles may well be executed in this research. The domain may be loaded with ternary hybrid nanofluid and the governing energy and Navier-Stokes equations might well be solved using finite element approach. The simulation is devised for a wide range of Darcy number, Rayleigh number, non-dimensional length between hot baffles. Examination of the influence of flow and thermal fields through isotherms, vertical and horizontal velocities, streamlines and Nusselt and Bejan numbers is carried out lucidly. Water + Carbon Nanotube (cylindrical)+ Al2O3(spherical)+ Graphene (platelet) is regarded as heat transfer medium within the enclosure. Results indicate that amplification of Darcy number upgrades vertical and horizontal velocities up to 88.51% and 83.77%, respectively, streamlines up to 88.12% as well as Nusselt numbers and isotherms effectively. Augmented Rayleigh number gives rise to intensification of isotherms, vertical and horizontal velocities, and streamlines while it exhibits reverse effect for average Bejan number. Moreover, rise of non-dimensional length between hot baffles from 0.4 to 0.6 leads to the encumbrance of maximum streamline, horizontal and vertical velocities by 11.32%, 8.6% & 5.12% respectively and lifts up average Bejan number by 24.17%

Statistical approach on optimizing heat transfer rate for Au/Fe3O4-blood nanofluid flow with entropy analysis used in drug delivery system

The current study focuses on utilizing an advanced statistical concept for optimizing rate of heat transfer in a micropolar nanofluid flow within a squeezing channel. The study employs RSM to plan experiments and analyze the role of distinct constraints on HT performance. Moreover, the inclusion of dissipative heat due to the interaction of applied magnetic field along with thermal radiation enriches the study. The proposed designed model is transformed to its non-dimensional form using appropriate similarity rules and then numerical simulation is presented to solve the set of formulated problem. However, the irreversibility process of the system is assessing by incorporating the entropy analysis. The validation along with the characteristic of the contributing factor is presented via the solution of the present design. The outcomes reveals that enhanced volume fraction generally increases viscosity of the fluid which resulted in a strong retardation in the fluid velocity. However, the entropy rate augments with an increasing Br. The results provide the optimal conditions for HTR for both of the nanofluids, which is relevant for applications in drug delivery systems. The advancement in optimizing HTR using RSM and the regression analysis using ANOVA (analysis of variance) may have potential implications for biomedical engineering