Entropy Generation and Optimization of Laminar Forced Convection Air Cooling in a Horizontal Channel Containing Heated Sources

Abstract

A forced convection air-cooling of two identical heat sources mounted in a horizontal channel is numerically studied. Four effects of Reynolds number, separation distance, height and width of the components on the flow structure and heat transfer inside the channel have been examined. The entropy generation minimization method (EGM) is employed to optimize the heat transfer and fluid flow in the channel. The flow field is governed by the Navier-Stokes equation and the thermal field by the energy equation. The finite volume method and the SIMPLER algorithm are used to solve the continuity, momentum, energy and entropy generation equations. Results show that the mean Nusselt number increases with increase of the following parameters: Reynolds number, separation distance, height and width of the components. However, these parameters increase the total entropy generation, and thus provokes the degradation of the fan energy. The optimal values of separation distance, height and width heat source are: [(Sopt= 1 with W=0.25, C=0.25, Re=50, η=1.134), (Copt=0.3 with W=0.25, S=0.25, Re=100, η=0.895) and (Wopt= 0.1 S=0.25, C=0.25, Re=200, η=1.004)], respectively, where η is the optimization factor (=Num/S T * ) and is defined as the ratio of Nusselt number to the total entropy generation. Finally, the optimal and the best configuration for maximum heat transfer and minimum entropy generation is observed at Re=50, S=1, C=0.25 and W=0.25.

Performance Analysis and Optimization of Regenerative Gas Turbine Power Plant using RSM

“…The model is empirically developed via regression from various response values or simulations. The numerical simulation outcomes were evaluated using the outcome of the surface interpolation process utilizing the subsequent second-order polynomial equation [29][30][31]:…”

“…where x i is the i th individual parameter of the empty encoded value, the uncoded value of the i th independent parameter is indicated by X i * similarly, at the middle point, the uncoded value of the i th individual parameter is designated by x ij , and the variation in the step value has been described as ∆X i [31].…”

Natural convection cooling process from two identical porous‐covering electronic components

“…The entropy generation induced by forced convection air cooling process from heated sources in a channel was numerically analyzed by Bensouici and Bensouici. 4 They observed that the increase of separation distance, height, and width of the components cause an increase in the total entropy generation and the average Nusselt number. Davalath and Bayazitoglu 5 studied the forced convection from several heat-conducting rectangular bodies in a channel.…”

A computational analysis of heat transport irreversibility phenomenon in a magnetized porous channel

“…The results showed that the MHD effects lessened the convective heat transport leading to further increment in conductive heat transport, the aspect ratio of the enclosure has considerably affected the temperature, concentration and velocity profiles. Bensouici and Bensouici (2017) have numerically applied the entropy generation minimization theory to optimize the heat transfer and the liquid motion in a horizontal channel to lessen the energy loss and to promote the cooling of heat sources. They obtained that a better configuration for highest heat transfer and minimum entropy was reached for the optimal Re number, separation distance, width and height of heat source, which are equal to 50, 1, 0.25 and 0.25, respectively.…”