A dual-phase-lag (DPL) transient non-Fourier heat transfer analysis of functional graded cylindrical material under axial heat flux

This study introduces an analysis of high-order dual-phase-lag (DPL) heat transfer equation and its thermodynamic consistency. The frameworks of extended irreversible thermodynamics (EIT) and traditional second law are employed to investigate the compatibility of DPL model by evaluating the entropy production rates (EPR). Applying an analytical approach showed that both the first- and second-order approximations of the DPL model are compatible with the traditional second law of thermodynamics under certain circumstances. If the heat flux is the cause of temperature gradient in the medium (over diffused or flux precedence (FP) heat flow), the DPL model is compatible with the traditional second law without any constraints. Otherwise, when the temperature gradient is the cause of heat flux (gradient precedence (GP) heat flow), the conditions of stable solution of the DPL heat transfer equation should be considered to obtain compatible solution with the local equilibrium thermodynamics. Finally, an insight inspection has been presented to declare precisely the influence of high-order terms on the EPRs.

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The exact analytical solution of the dual-phase-lag two-temperature bioheat transfer of a skin tissue subjected to constant heat flux

Scientific Reports ◽

10.1038/s41598-020-73086-0 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Hamdy M. Youssef ◽

Najat A. Alghamdi

Keyword(s):

Heat Flux ◽

Analytical Solution ◽

Exact Analytical Solution ◽

Constant Heat Flux ◽

Bioheat Transfer ◽

Skin Tissue ◽

Phase Lag ◽

Dual Phase ◽

Constant Heat ◽

Two Temperature

Abstract This work is dealing with the temperature reaction and response of skin tissue due to constant surface heat flux. The exact analytical solution has been obtained for the two-temperature dual-phase-lag (TTDPL) of bioheat transfer. We assumed that the skin tissue is subjected to a constant heat flux on the bounding plane of the skin surface. The separation of variables for the governing equations as a finite domain is employed. The transition temperature responses have been obtained and discussed. The results represent that the dual-phase-lag time parameter, heat flux value, and two-temperature parameter have significant effects on the dynamical and conductive temperature increment of the skin tissue. The Two-temperature dual-phase-lag (TTDPL) bioheat transfer model is a successful model to describe the behavior of the thermal wave through the skin tissue.

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A meshless radial basis function based method for modeling dual-phase-lag heat transfer in irregular domains

Computers & Mathematics with Applications ◽

10.1016/j.camwa.2020.12.018 ◽

2021 ◽

Vol 85 ◽

pp. 1-17

Author(s):

Ji Lin ◽

Hao Yu ◽

Sergiy Reutskiy ◽

Yuan Wang

Keyword(s):

Heat Transfer ◽

Radial Basis Function ◽

Basis Function ◽

Phase Lag ◽

Dual Phase ◽

Irregular Domains ◽

Radial Basis

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Heat Transfer Analysis of Laminar Pulsating Flow in a Rectangular Channel Using Infrared Thermography

Journal of Heat Transfer ◽

10.1115/1.4052686 ◽

2021 ◽

Author(s):

Richard Blythman ◽

Sajad Alimohammadi ◽

Nicholas Jeffers ◽

Darina B. Murray ◽

Tim Persoons

Keyword(s):

Heat Transfer ◽

Heat Flux ◽

Analytical Solution ◽

Local Time ◽

Rectangular Channel ◽

Pulsating Flow ◽

Time Dependent ◽

Heat Transfer Analysis ◽

Flux Boundary Condition ◽

Hydrodynamic Behaviour

Abstract While numerous applied studies have successfully demonstrated the feasibility of unsteady cooling solutions, a consensus has yet to be reached on the local instantaneous conditions that result in heat transfer enhancement. The current work aims to experimentally validate a recent analytical solution (on a local time-dependent basis) for the common flow condition of a fully-developed incompressible pulsating flow in a uniformly-heated vessel. The experimental setup is found to approximate the ideal constant heat flux boundary condition well, especially for the decoupled unsteady scenario where the amplitude of the most significant secondary contributions (capacitance and lateral conduction) amounts to 1.2% and 0.2% of the generated heat flux, respectively. Overall, the experimental measurements for temperature and heat flux oscillations are found to coincide well with a recent analytical solution to the energy equation by the authors. Furthermore, local time-dependent heat flux enhancements and degradations are observed to be qualitatively similar to those of wall shear stress from a previous study, suggesting that the thermal performance is indeed influenced by hydrodynamic behaviour.

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