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In the last two decades, heat transfer study on discrete heat sources has become a subject of increased interest due to advances in the electronics industry. Increased power dissipation is the most significant feature of new generation electronic devices and more significant heat flux densities are obtained as a result of miniaturization. Consequently, the assumption of cooling of electronic devices has increased interest in the analysis of fluid flow and heat transfer in discrete heating situations. Previous works have studied the natural, mixed, and forced convection in inclined channels due to their practical applications such as electronic systems, high performance heat exchangers, chemical process equipments, combustion chambers, environmental control systems and so on. An interesting study was reported on the fluid flow and heat transfer characteristics associated with cooling an in-line array of discrete protruding heated blocks in a channel by using a single laminar slot air jet (Arquis et al., 2007). Numerical experiments were carried out for different values of jet Reynolds number, channel height, slot width, spacing between blocks, block height, and block thermal conductivity. The effects of variation of these parameters were detailed to illustrate important fundamental and practical results that are relevant to the thermal management of electronic packages. In general, the effective cooling of blocks was observed to increase with the increase of Reynolds number and the decrease of channel height. Circulation cells that may appear on the top surface of the downstream blocks were shown to decrease the value of Nusselt number for these blocks. The values of surface averaged Nusselt number attained their maximum at the block just underneath the impinging air jet, decreased for the downstream blocks, and approximately reached a constant value after the third block. A numerical study (Madhusudhana & Narasimham, 2007) was carried out on conjugate mixed convection arising from protruding heat generating ribs attached to substrates forming a series of vertical parallel plate channels. A channel with periodic boundary conditions in the transverse direction was considered for analysis where identical disposition and heat generation of the ribs on each board were assumed. The governing equations were discretised using a control volume approach on a staggered mesh and a pressure correction method was employed for the pressure–velocity coupling. The solid regions were considered as fluid regions with infinite viscosity; and the thermal coupling between the solid and fluid regions was taken into account by the harmonic thermal |
