Heat Transfer In Cavity Research Articles

EFFECT OF WALL CONDUCTION AND RADIATION ON NATURAL CONVECTION IN A RECTANGULAR CAVITY

Numerical results have been obtained for the effects of wall conduction and radiation heat exchange between surfaces on laminar natural-convection heat transfer in a two-dimensional rectangular cavity. Parametric heat transfer calculations have been performed and results are presented In graphic and tabular form. Local and average Nusselt numbers along the cavity walls are reported for a range of parameters of physical interest. The findings suggest that the local or the average Nusselt number may not be a meaningful parameter for use in conjugate heat transfer problems. The results indicate that natural-convection heat transfer in the cavity is reduced by heat conduction in the walls and radiation exchange among surfaces.

Finite Difference Analysis of Laminar Separated Forced Convection in Cavities

Results are presented for a comprehensive numerical analysis of the two-dimensional heat transfer in cavities of rectangular profiles. The walls of the cavity are held at a uniform temperature and calculations are carried out at various aspect ratios and Reynolds numbers in laminar flow. The numerical technique is based on a hybrid upwind/central differencing of the governing differential equations that are first integrated over control volumes surrounding the node points in a rectilineal, nonuniform grid system. Results indicate that while the average Nusselt number in the cavity is related to the Reynolds number raised to a power, the latter depends on the aspect ratio and varies between the cavity floor and the side walls. The influence of the upstream boundary layer thickness is found to be negligible. The numerical results are found to be well represented by the following equation: Nu¯t=0.0345(Res)0.46(w/s)−0.142