MHD micropolar nanofluid flow through an inclined channel with entropy generation subjected to radiative heat flux, viscous dissipation and multiple slip effects

PurposeMiniaturization with high thermal performance and lower cost is one of the advanced developments in industrial science chemical and engineering fields including microheat exchangers, micro mixers, micropumps, cooling microelectro mechanical devices, etc. In addition to this, the minimization of the entropy is the utilization of the energy of thermal devices. Based on this, in the present investigation, micropolar nanofluid flow through an inclined channel under the impacts of viscous dissipation and mixed convection with velocity slip and temperature jump has been numerically studied. Also the influence of magnetism and radiative heat flux is used.Design/methodology/approachThe nonlinear system of ordinary differential equations are obtained by applying suitable dimensionless variables to the governing equations, and then the Runge–Kutta–Felhberg integration scheme is used to find the solution of velocity and temperature. Entropy generation and Bejan number are calculated via using these solutions.FindingsIt is established to notice that the entropy generation can be improved with the aspects of viscous dissipation, magnetism and radiative heat flux. The roles of angle of inclination (α), Eckert number (Ec), Reynolds number (Re), thermal radiation (Rd), material parameter (K), slip parameter (δ), microinertial parameter (aj), magnetic parameter (M), Grashof number (Gr) and pressure gradient parameter (A) are demonstrated. It is found that the angle of inclination and Grashof number enhances the entropy production while it is diminished with material parameter and magnetic parameter.Originality/valueElectrically conducting micropolar nanofluid flow through an inclined channel subjected to the friction irreversibility with temperature jump and velocity slip under the influence of radiative heat flux has been numerically investigated.

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Entropy generation in magneto nanofluid flow with Joule heating and thermal radiation

World Journal of Engineering ◽

10.1108/wje-06-2019-0166 ◽

2020 ◽

Vol 17 (1) ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Mohamed Almakki ◽

Hiranmoy Mondal ◽

Precious Sibanda

Keyword(s):

Thermal Radiation ◽

Viscous Dissipation ◽

Entropy Generation ◽

Joule Heating ◽

Transfer Model ◽

Nanofluid Flow ◽

Content Type ◽

Flow Equations ◽

Micropolar Nanofluid ◽

The Impact

Purpose This paper aims to investigate entropy generation in an incompressible magneto-micropolar nanofluid flow over a nonlinear stretching sheet. The flow is subjected to thermal radiation and viscous dissipation. The energy equation is extended by considering the impact of the Joule heating term because of an imposed magnetic field. Design/methodology/approach The flow, heat and mass transfer model are solved numerically using the spectral quasilinearization method. An analysis of the performance of this method is given. Findings It is found that the method is robust, converges fast and gives good accuracy. In terms of the physically significant results, the authors show that the irreversibility caused by the thermal diffusion the dominants other sources of entropy generation and the surface contributes significantly to the total irreversibility. Originality/value The flow is subjected to a combination of a buoyancy force, viscous dissipation, Joule heating and thermal radiation. The flow equations are solved numerically using the spectral quasiliearization method. The impact of a range of physical and chemical parameters on entropy generation, velocity, angular velocity, temperature and concentration profiles are determined. The current results may help in industrial applicants. The present problem has not been considered elsewhere.

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Second law analysis on Hall effect of natural convection flow through vertical channel in the presence of uniform heat source/sink

International Journal of Numerical Methods for Heat &amp Fluid Flow ◽

10.1108/hff-10-2019-0767 ◽

2020 ◽

Vol 30 (10) ◽

pp. 4403-4423

Author(s):

A. Roja ◽

B.J. Gireesha

Keyword(s):

Heat Flux ◽

Heat Source ◽

Viscous Dissipation ◽

Joule Heating ◽

Radiative Heat ◽

Vertical Channel ◽

Radiative Heat Flux ◽

Content Type ◽

Uniform Heat ◽

Source Sink

Purpose Microfluidics is one of the extensive elaborated technologies in thermal and engineering fields due to its wide range of applications, such as micro heat exchangers, micro mixture and microchannel heat sinks, which is used to develop a large number of microscopic devices and systems. Enhancement of thermal energy using verity of nanoliquids is one of the challenges in these applications of microfluidics. Therefore, using single wall carbon nanotubes for enhancement of thermal energy in microchannel is the main purpose of this study. Hall effect of natural convection flow in a vertical channel with slip and temperature jump condition is considered. The impacts of radiative heat flux, uniform heat source/sink, viscous dissipation and joule heating are also taken into account. Design/methodology/approach Suitable non-dimension variables are applied to the governing equations to reduce the system into ordinary differential equations. The reduced nonlinear system is then solved numerically using Runge–Kutta–Fehlberg fourth–fifth-order method along with shooting technique. The impact of different pertinent parameters on numerical solutions of primary velocity, secondary velocity, temperature, entropy generation and Bejan number is comprehensively discussed in detail. Also, the obtained numerical results are compared with existing one which perfectly found to be in good agreement. Findings It is established that, with the aspects of Joule heating, viscous dissipation, radiative heat flux and uniform heat source/sink, the production in the entropy can be improved. Further, it is found that the increasing ratio of wall ambient temperature difference and nanoparticle volume fraction leads to enhance the entropy generation. The same effect reverses with increasing values of fluid wall interaction parameter (FWIP) and rare faction. The irreversibility ratio enhances with larger values of nanoparticle volume fraction and decelerates with increment values of FWIP. Originality/value The impact of single wall carbon nanoliquid in a vertical channel flow by using radiative heat flux, heat source/sink, joule heating and viscous dissipation is first time investigated. Further, the influence of Hall current is explored in detail.

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Finite element analysis of micropolar nanofluid flow through an inclined microchannel with thermal radiation

Multidiscipline Modeling in Materials and Structures ◽

10.1108/mmms-11-2019-0198 ◽

2020 ◽

Vol 16 (6) ◽

pp. 1521-1538 ◽

Cited By ~ 1

Author(s):

N.S. Shashikumar ◽

Madhu Macha ◽

B.J. Gireesha ◽

Naikoti Kishan

Keyword(s):

Finite Element ◽

Thermal Radiation ◽

Entropy Generation ◽

Joule Heating ◽

Volume Fraction ◽

Entropy Generation Rate ◽

Nanofluid Flow ◽

Content Type ◽

Micropolar Nanofluid ◽

Flow Through

PurposeIn recent years, microfluidics has turned into a very important region of research because of its wide range of applications such as microheat exchanger, micromixers fuel cells, cooling systems for microelectronic devices, micropumps and microturbines. Therefore, in this paper, micropolar nanofluid flow through an inclined microchannel is numerically investigated in the presence of convective boundary conditions. Heat transport of fluid includes radiative heat, viscous and Joule heating phenomena.Design/methodology/approachGoverning equations are nondimensionalized by using suitable dimensionless variables. The relevant dimensionless ordinary differential systems are solved by using variational finite element method. Detailed computations are done for velocity, microrotation and temperature functions. The influence of various parameters on entropy generation and the Bejan number is displayed and discussed.FindingsIt is established that the entropy generation rate increased with both Grashof number and Eckert number, while it decreased with nanoparticle volume fraction and material parameter. Temperature is decreased by increasing the volume fraction of Ag nanoparticle dispersed in water.Originality/valueAccording to the literature survey and the best of the author’s knowledge, no similar studies have been executed on micropolar nanofluid flow through an inclined microchannel with effect of viscous dissipation, Joule heating and thermal radiation.

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Dynamic consequences of nonlinear radiative heat flux and heat generation/absorption effects in cross-diffusion flow of generalized micropolar nanofluid

Case Studies in Thermal Engineering ◽

10.1016/j.csite.2021.101451 ◽

2021 ◽

pp. 101451

Author(s):

M. Ijaz Khan ◽

Kamel Al-Khaled ◽

Sami Ullah Khan ◽

Taseer Muhammad ◽

Hassan Waqas ◽

...

Keyword(s):

Heat Flux ◽

Heat Generation ◽

Radiative Heat ◽

Radiative Heat Flux ◽

Diffusion Flow ◽

Cross Diffusion ◽

Micropolar Nanofluid ◽

Nonlinear Radiative Heat Flux

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Nonlinear radiative heat flux in Oldroyd-B nanofluid flow with Soret and Dufour effects

Applied Nanoscience ◽

10.1007/s13204-019-01028-y ◽

2019 ◽

Vol 10 (8) ◽

pp. 3103-3113 ◽

Cited By ~ 6

Author(s):

Tasawar Hayat ◽

Madiha Rashid ◽

Ahmed Alsaedi

Keyword(s):

Heat Flux ◽

Radiative Heat ◽

Radiative Heat Flux ◽

Nanofluid Flow ◽

Soret And Dufour Effects ◽

Nonlinear Radiative Heat Flux

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Effect of viscous dissipation on forced convection for laminar flow through a straight regular polygonal duct using BEM method

International Journal of Numerical Methods for Heat &amp Fluid Flow ◽

10.1108/hff-09-2017-0371 ◽

2018 ◽

Vol 28 (1) ◽

pp. 220-238 ◽

Cited By ~ 16

Author(s):

Tomasz Janusz Teleszewski ◽

Slawomir Adam Sorko

Keyword(s):

Heat Flux ◽

Nusselt Number ◽

Laminar Flow ◽

Forced Convection ◽

Viscous Dissipation ◽

Wall Temperature ◽

Bulk Temperature ◽

Brinkman Number ◽

Content Type ◽

Flow Through

Purpose The purpose of this paper is to investigate the effect of the viscous dissipation of laminar flow through a straight regular polygonal duct on forced convection with constant axial wall heat flux with constant peripheral wall temperature using the boundary element method (BEM). Design/methodology/approach Both the wall heating case and the wall cooling case are considered. Applying the velocity profile obtained for the duct laminar flow and the energy equation with the viscous dissipation term is solved exactly for the constant wall heat flux using the BEM. The numerical values are obtained by means of a computer program, written by the authors in Fortran. The results of the BEM approach are verified by analytic models. Nusselt numbers are obtained for flows with a different number of sides of a regular polygonal duct and Brinkman numbers. Findings When the difference in temperature between the wall temperature and the fluid bulk temperature changes the sign, then the functions of the Nusselt number with the Brinkman number generated some singularities (BrqLs). For the Brinkman number referring to the total wall linear power, with the increasing value of the number of sides of a regular polygonal duct, BrqLs decreases in the range of 3 ≤ n < ∞. If the BrqL < BrqLs, it is possible to note that, in general, the Nusselt number is higher for cross-sections having a lower value of the number of sides of a regular polygonal duct. For BrqL > BrqLs, this rule is reversed. Originality/value This paper illustrates the effects of viscous dissipation on laminar forced convective flow in regular polygon ducts with a different number n of sides. A compact relationship for the Nusselt number vs the Brinkman number referring to the temperature difference between the wall temperature and the fluid bulk temperature and the Brinkman number, which is based on the total wall linear power, have been proposed.

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