Theoretical Exploration of Exponential Heat Source and Thermal Stratification Effects on The Motion of 3-Dimensional Flow of Casson Fluid Over a Low Heat Energy Surface at Initial Unsteady Stage

AbstractWithin the last few decades, experts and scientists dealing with the flow of non-Newtonian fluids (most especially Casson fluid) have confirmed the existence of such flow on a stretchable surface with low heat energy (i.e. absolute zero of temperature). This article presents the motion of a three-dimensional of such fluid. Influence of uniform space dependent internal heat source on the intermolecular forces holding the molecules of Casson fluid is investigated. It is assumed that the stagnation flow was induced by an external force (pressure gradient) together with impulsive. Based on these assumptions, variable thermophysical properties are most suitable; hence modified kinematic viscosity model is presented. The system of governing equations of 3-dimensional unsteady Casson fluid was non-dimensionalized using suitable similarity transformation which unravels the behavior of the flow at full fledge short period. The numerical solution of the corresponding boundary value problem (ODE) was obtained using Runge-Kutta fourth order along with shooting technique. The intermolecular forces holding the molecules of Casson fluid flow in both horizontal directions when magnitude of velocity ratio parameters are greater than unity breaks continuously with an increase in Casson parameter and this leads to an increase in velocity profiles in both directions.

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THERMAL TRANSPORT PHENOMENON IN PROCESSED MEAT HEATED BY LASER HEAT SOURCE

Journal of Mechanics in Medicine and Biology ◽

10.1142/s0219519408002553 ◽

2008 ◽

Vol 08 (01) ◽

pp. 17-25

Author(s):

SHUICHI TORII ◽

WEN-JEI YANG

Keyword(s):

Heat Source ◽

Thermal Wave ◽

Numerical Technique ◽

Internal Heat ◽

Internal Heat Source ◽

Conservation Equation ◽

Processed Meat ◽

Laser Heat ◽

Short Period ◽

Laser Heat Source

The present study deals with the effect of laser radiation on the propagation phenomenon of a thermal wave in processed meat subjected to symmetrical heating on both sides. Laser heating is modeled as an internal heat source with various time characteristics. The Cattaneo heat flux law, together with the energy conservation equation, is solved by a numerical technique based on an explicit scheme, i.e. MacCormack's predictor-corrector scheme. The study concludes that (1) if the absorption coefficient of the continuously operated laser heat source increases, then temperature overshoot occurs in processed meat within a very short period of time; (2) the overshoot and oscillation of thermal wave depend on the frequency of the heat source time characteristics; and (3) the criterion for the occurrence of thermal wave in a thin processed meat is the thickness of the order of about 1 mm.

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THERMAL-WAVE PROPAGATION PHENOMENON IN THIN FILMS HEATED WITH LASER HEAT SOURCE

Journal of Mechanics in Medicine and Biology ◽

10.1142/s0219519404001235 ◽

2004 ◽

Vol 04 (04) ◽

pp. 435-445 ◽

Cited By ~ 1

Author(s):

SHUICHI TORII ◽

WEN-JEI YANG

Keyword(s):

Thin Film ◽

Heat Source ◽

Thermal Wave ◽

Numerical Study ◽

Numerical Technique ◽

Internal Heat ◽

Time History ◽

Internal Heat Source ◽

Hyperbolic Heat Conduction ◽

Short Period

A numerical study is performed on the effect of laser radiation on the propagation phenomenon of a thermal wave in a very thin film subjected to a symmetrical heating on both sides. Laser heating is modelled as an internal heat source. The non-Fourier, hyperbolic heat conduction equation is solved by a numerical technique based on MacCormack's predictor-corrector scheme. Consideration is given to the time history of heat transfer behaviour before and after symmetrical collision of wave fronts from two sides of a film. It is disclosed that (i) if the absorption coefficient of the laser increases, temperature overshoot causes in a very thin film within a very short period of time, and (ii) the overshoot and oscillation of thermal wave depend on the frequency of the heat source time characteristics. This trend becomes minor in a thick film.

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Second law analysis of MHD natural convection slip flow of Casson fluid through an inclined microchannel

Multidiscipline Modeling in Materials and Structures ◽

10.1108/mmms-11-2019-0189 ◽

2020 ◽

Vol 16 (6) ◽

pp. 1435-1455 ◽

Cited By ~ 2

Author(s):

B.J. Gireesha ◽

A. Roja

Keyword(s):

Heat Source ◽

Viscous Dissipation ◽

Entropy Generation ◽

Joule Heating ◽

Internal Heat ◽

Internal Heat Source ◽

Casson Fluid ◽

Content Type ◽

Flow Through ◽

Source Sink

PurposeMicrofluidics is one of the interesting areas of the research in thermal and engineering fields due to its wide range of applications in a variety of heat transport problems such as micromixers, micropumps, cooling systems for microelectromechanical systems (MEMS) micro heat exchangers, etc. Lower cost with better thermal performance is the main objective of these devices. Therefore, in this study, the entropy generation in an electrically conducting Casson fluid flow through an inclined microchannel with hydraulic slip and the convective condition hves been numerically investigated. Aspects of viscous dissipation, natural convection, joule heating, magnetic field and uniform heat source/sink are usedDesign/methodology/approachSuitable non-dimensional variables are used to reduce the non-linear system of ordinary differential equations, and then this system is solved numerically using Runge-Kutta-Fehlberg fourth fifth order method along with shooting technique. The obtained numerical solutions of the fluid velocity and temperature are used to characterize the entropy generation and Bejan number. Also, the Nusselt number and skin friction coefficient for various values of parameters are examined in detail through graphs. The obtained present results are compared with the existing one which is perfectly found to be in good agreement.FindingsIt is established that the production of the entropy can be improved with the aspects of joule heating, viscous dissipation and internal heat source/sink. The entropy generation enhances for increasing values of Casson Parameter (β) and Biot number (Bi). Furthermore, it is interestingly noticed that the enhancement of Reynolds number and uniform heat source/sink shows the dual behaviour of the entropy generation due to significant influence of the viscous forces in the region close to the channel walls. It was observed that increasing behaviour of the heat transfer rate for enhancement values of the Eckert number and heat source/sink ratio parameter and the drag force are retarded with higher estimations of Reynolds number.Originality/valueEntropy generation analysis on MHD Casson fluid flow through an inclined microchannel with the aspects of convective, Joule heating, viscous dissipation, magnetism, hydraulic slip and internal heat source/sink has been numerically investigated.

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