The goal of this numerical investigation is to evaluate the impact of fin arrangement on the hydrothermal and irreversibility analysis of a biologically ecofriendly prepared water-Ag nanofluid flowing inside a microchannel heatsink. Three bifurcation microchannels heatsinks with straight channels, inline fins, and staggered fins are considered. Two-phase mixture method is used to model the nanofluid behaviour precisely. The influences of nanoparticle volume fraction (φ) and Reynolds number (Re) on the parameters of convective coefficient, CPU surface temperature, pumping power, heat transfer and fluid friction irreversibilities are examined. It was found that the hydrothermal characteristics and irreversibility behaviour of the heatsinks equipped with fins are better than those of the heatsink with straight channels. The results showed that the best overall first-law and second law performances respectively belong to the heatsink equipped with staggered (except for the φ = 0.1%, φ = 0.5% and Re = 500) and inline fins. Moreover, the application of water-Ag nanofluid in the studied heatsinks was more justifiable for high Re and φ. Finally, it was revealed that boosting both the Re and φ results in an augmentation in the second law performance of nanofluid in the studied heatsinks.
