Thermo-hydraulic and entropy generation analysis of recharging microchannel using water-based graphene-silver hybrid nanofluid

This work numerically investigates thermo-hydraulic and entropy generation characteristics of water-based graphene-silver (Gr-Ag) hybrid nanofluid with temperature-dependent properties in recharging microchannel (RMC). The thermal, hydraulic, and entropy generation characteristics in recharging microchannel are examined for different nanofluid volume concentrations and inlet velocity. The outcome of this study reveals that the utilization of Gr-Ag hybrid nanofluid in recharging microchannel enhances heat transfer performance. With an increase in both nanofluid volume concentration and fluid inlet velocity, substrate maximum temperature and thermal resistance decrease, whereas the uniformity in temperature distribution and average heat transfer coefficient enhanced. Moreover, the use of hybrid nanofluid in recharging microchannel shows higher pressure drop and requires more pumping power. Recharging microchannel (RMC) exhibits better overall performance compared to simple microchannel (SMC) with maximum performance factor value of 1.72. Further, frictional entropy generation increases, and thermal entropy generation decreases with increasing nanofluid volume concentration and inlet velocity. Both total entropy generation and Bejan number decrease with nanofluid volume concentration. Overall, the use of recharging microchannel (RMC) can be beneficial for high heat flux removal applications from both first and second law of thermodynamics perspective. Second, the utilization of water-based Gr-Ag hybrid nanofluid is beneficial when pumping power is not a constraint.

Automated summary

This study numerically investigates the thermo-hydraulic and entropy generation characteristics of water-based graphene-silver hybrid nanofluid in a recharging microchannel. The results show that using the hybrid nanofluid enhances heat transfer performance but also increases pressure drop and pumping power requirements.