Analysis of modified Fourier law and melting heat transfer in a flow involving carbon nanotubes

The dynamics of non-Newtonian liquids flow along with suspension of nanoparticles are pretty exciting with many industrial applications. In view of this, we examined Darcy-Forchheimer two-dimensional carbon nanotubes flow in light of a melting surface with warm nonlinear radiation, Cattaneo-Christov heat flux and slip condition. Similarity transformations are utilized to deal with the problem equations for non-dimensionality. Runge-Kutta-Felberg-45 method by adopting shooting scheme is applied for the simulation of the demonstrated equations. The thermal framework is investigated for all the implanted parameters whose impacts are appeared through various graphs. There exist fascinating outcomes because of the impacts of various constraints on various profiles. Results reveals that, velocity and corresponding thickness of the boundary layer declines for rising values of Forchheimer parameter and porosity parameter. Moreover, rate of declination of velocity gradient in MWCNT-water stream is slower than SWCNT-water stream. Also, inclined values of melting parameter display a diminishing pattern for the temperature field. Further, rate of declination in heat transfer of SWCNT-water stream is faster than MWCNT-water stream.

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Heat Transfer Enhancement by Coupling of Carbon Nanotubes and SiO2 Nanofluids: A Numerical Approach

Processes ◽

10.3390/pr7120937 ◽

2019 ◽

Vol 7 (12) ◽

pp. 937 ◽

Cited By ~ 2

Author(s):

Fitnat Saba ◽

Saima Noor ◽

Naveed Ahmed ◽

Umar Khan ◽

Syed Tauseef Mohyud-Din ◽

...

Keyword(s):

Heat Transfer ◽

Carbon Nanotubes ◽

Three Dimensional ◽

Numerical Approach ◽

Skin Friction Coefficient ◽

Squeezing Flow ◽

Hybrid Nanofluid ◽

Governing Equations ◽

Similarity Transformations ◽

Rotating Channel

This article comprises the study of three-dimensional squeezing flow of (CNT-SiO2/H2O) hybrid nanofluid. The flow is confined inside a rotating channel whose lower wall is stretchable as well as permeable. Heat transfer with viscous dissipation is a main subject of interest. We have analyzed mathematically the benefits of hybridizing SiO 2 -based nanofluid with carbon nanotubes ( CNTs ) nanoparticles. To describe the effective thermal conductivity of the CNTs -based nanofluid, a renovated Hamilton–Crosser model (RHCM) has been employed. This model is an extension of Hamilton and Crosser’s model because it also incorporates the effect of the interfacial layer. For the present flow scenario, the governing equations (after the implementation of similarity transformations) results in a set of ordinary differential equations (ODEs). We have solved that system of ODEs, coupled with suitable boundary conditions (BCs), by implementing a newly proposed modified Hermite wavelet method (MHWM). The credibility of the proposed algorithm has been ensured by comparing the procured results with the result obtained by the Runge-Kutta-Fehlberg solution. Moreover, graphical assistance has also been provided to inspect the significance of various embedded parameters on the temperature and velocity profile. The expression for the local Nusselt number and the skin friction coefficient were also derived, and their influential behavior has been briefly discussed.

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Inverse Solution of Radiative Heat Transfer in Two-Dimensional Irregularly Shaped Enclosures

10.1115/imece2000-1373 ◽

2000 ◽

Author(s):

Hakan Ertürk ◽

Ofodike A. Ezekoye ◽

John R. Howell

Keyword(s):

Heat Transfer ◽

Heat Flux ◽

Radiative Heat Transfer ◽

Radiative Heat ◽

Industrial Applications ◽

Dominant Mode ◽

Inverse Solution ◽

Solution Technique ◽

Complex Geometries ◽

Two Dimensional

Abstract An inverse solution technique is used to predict the necessary temperature and heat flux distributions of the heater section of a two-dimensional enclosure so the heater satisfies the specified heat flux and temperature distributions of design surfaces, while satisfying one thermal boundary condition for the other walls. Radiation is the dominant mode of heat transfer in systems where high temperatures are present; therefore, it is considered as the only mode of heat transfer in this study. The two-dimensional enclosures considered in this study are made up of straight segments, positioned so that they form irregularly shaped enclosures approximating situations for many of the real cases in industrial applications. The enclosure walls are gray, emitting diffusely and reflecting either diffusely or specularly. The medium inside the enclosure may be transparent, absorbing-emitting or absorbing-emitting and isotropically scattering. For the participating medium cases, the gray medium is considered as isothermal, homogeneous and isotropically scattering. The Monte Carlo method is used for formulation of radiative heat transfer. The method is preferred for its accuracy and ease of handling complex geometries and various surface and medium properties. The main contribution of this study is to solve inverse design problems for complex geometries that contain blockage and shading effects, as could be the case in many real industrial applications. The resulting system of equations, which includes Fredholm equations of the first kind, is known to be highly ill-conditioned in nature. The solution for this ill-conditioned system is handled by the conjugate gradient method, an iterative solution method, which obtains smooth and very accurate solutions in a few steps for linear systems.

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