Numerical Simulation of Natural Convection in a Porous Cavity with Linearly Temperature Distributions Under the Local Thermal Nonequilibrium Condition

Abstract

A numerical investigation of the natural convection heat transfer in a rectangular cavity filled with a heat-generating porous medium by adopting the local thermal nonequilibrium (LTNE) model is reported in this paper. The top and bottom walls of the enclosure are adiabatic, the left wall is linearly cooled, and the right wall is cooled by a linear or uniform temperature profile. The results show that the isotherms for the fluid and solid phases become similar with the increase of the interphase heat transfer coefficient H; the increasing heat transfer between the two phases brings their temperatures closer to each other and thus the solid and fluid phases are in a state of the thermal equilibrium at higher values of H. For case A, the interphase heat transfer coefficient has little influence on the heat transfer rate of the solid phase of the porous cavity and the heat transfer profile of the solid phase (Nu sy ) is symmetrical with respect to the center point of line Y ¼ 0.5. For case B, the interphase heat transfer coefficient H has a significant effect on that at the right wall, and the total heat transfer of the heat-generating porous cavity is implemented by the right-side wall. The total heat transfer rate Q of case B is higher than that of case A at a high thermal conductivity ratio c (c ¼ 1, 10).

Nanofluid Transport in Porous Media: A Review

“…The results showed that, compared with the uniform boundary conditions, the sinusoidal boundary conditions can enhance the heat transfer rate of a porous cavity. Wu et al (2015b) numerically investigated a two-dimensional steady-state fluid flow and heat transfer problem inside an enclosure filled with a heat-generating porous medium by linearly thermal boundary condition. The study used the generalized non-Darcy model to describe the flow field.…”

Conjugate local thermal non-equilibrium heat transfer in a cavity filled with a porous medium: Analysis of the element location

“…The authors revealed that the overall heat transfer (Nusselt number) can be improved by imposing sinusoidal thermal boundary condition when compared to the case of a constant wall temperature. Wu et al [25] also analysed the effect non uniform wall temperature on the natural convection heat transfer in a cavity by considering a linear variation of the wall temperature. Other aspects of LTNE natural convection in a cavity, such as the effects of partially active wall with sinusoidal temperature [25], cavity aspect ratio [26], nanofluids [27] and cavity partially filled with porous media [28], have been addressed in the literature.…”

Numerical Study of Natural Convection in a Porous Cavity with Sinusoidal Thermal Boundary Condition

“…It is a well‐known fact that, owing to the widespread engineering applications, convective heat transfer in fluid‐saturated, heat‐generating porous enclosures has been a research topic of practical importance during the past three decades 1–10. Some of these applications are: management of radioactive waste storage, design and operation of nuclear reactor cores, cooling of electronic devices, design of chemical catalytic reactors, storage of agricultural and food products, etc.…”