Numerical study of entropy generation in a microchannel heat sink with fan-shaped cavity along with different ribs and secondary channels

The aim of this numerical work is to overcome the underlying challenges of flow friction, heat transfer associated irreversibility and to minimize the total entropy generation, causing a notable decline in cooling performance. The current research deals with these issues by developing a novel design of different rib structures arranged symmetrically inside fan shaped cavity arranged to the side walls with integration of secondary channels. The temperature dependent thermos-physical properties, laminar flow at Re from 136.3 to 588.4, has been employed to this numerical model in order to study the effect of secondary channel addition to the cavity and rib set in formation of secondary vortices. The results in these cases were examined for effect of design parameters on thermal, frictional irreversibilities using the analysis of variance (ANOVA) in response surface methodology (RSM) under minimization scale as performance factor, achieved in all rib cases on average R 2 of 96.6%, which demonstrates that statistical model developed is significant. The new heat sink design found highly effective in heat extraction, the comparative study of various rib structures showing a decreasing trend in at Re number (136.3 ≤ Re ≤ 326.12), this constant decrement trend is continued up to Re at 588.4 in the case of entropy generation due to heat transfer. Furthermore, parametric study reveals that associated pressure drop penalty with addition of secondary channel was proved much smaller in comparison to the only ribs and cavities, on analyzing it was found that geometric parameters combination α = 1.00, β = 1.25, γ = 0.045, ϕ = 0.250 employed in the case of rectangular rib, (FR-SC), forward triangular rib (FF-SC) are exhibiting lowest entropy generation number of 0.35, 0.36 respectively at Re= 326.12.