Open Access
ARTICLE
CONDUCTION, CONVECTION, AND RADIATION IN A CLOSED CAVITY WITH A LOCAL RADIANT HEATER
Geniy V. Kuznetsov, Alexander E. Nee*
National Research Tomsk Polytechnic University, Tomsk, 634050, Russia
* Corresponding Author: Email:
Frontiers in Heat and Mass Transfer 2018, 10, 1-9. https://doi.org/10.5098/hmt.10.26
Abstract
This study deals with the numerical investigation of combined heat transfer via conduction, laminar natural convection, and surface radiation in a
closed rectangular cavity with a radiant heating source. Unsteady two-dimensional equations of mass, momentum, and energy conservation for
complex heat transfer process under study were formulated in terms of the vorticity – stream function – temperature variables and solved by means of
the finite difference method on a uniform grid. Developed numerical code was validated against two benchmark problems of convective and
convective-radiative heat transfer. When analyzing complex heat transfer regularities, we varied the following parameters: dimensionless time
5 ≤ τ ≤ 800, Rayleigh number 6·10
4 ≤
Ra ≤ 4·10
6, conduction-radiation number 19.71 ≤
Nr ≤ 78.84, surface emissivity 0.2 ≤
ε ≤ 0.9, emitter
length 0.1 ≤
D ≤ 1 , walls thickness 0.05 ≤
M ≤ 0.25. According to the results of mathematical modelling, it was found that the radiant parameters
significantly affected the formation of differential and integral characteristics of conjugate heat transfer. Along with that the convective Nusselt
number was slightly changed in geometrical and physical conditions under study. An increase in the walls thickness led to a reduce in the
temperature of the air cavity. However, the effect of wall thickness on the convective and radiative Nusselt numbers was not significant.
Keywords
Cite This Article
Kuznetsov, G. V., Nee, A. E. (2018). CONDUCTION, CONVECTION, AND RADIATION IN A CLOSED CAVITY WITH A LOCAL RADIANT HEATER.
Frontiers in Heat and Mass Transfer, 10(1), 1–9.