The aim of this work is to study the hydrothermal and irreversibility characteristics in forced convection flow of
Ag-MgO/water hybrid nanofluid through a sinusoidal hairpin heat-exchanger, numerically. The impact of nanoadditive
concentration (φ), Reynolds number (Re) and amplitude of the sinusoidal tube are investigated on the
heat-exchanger performance form both the first law and second law points of view. The considered performance
matrices are heat transfer rate, total heat transfer coefficient, heat-exchanger effectiveness, pressure loss,
pumping power as well as the irreversibilities due to flow friction and heat transfer. The findings indicated that
boosting the Re and φ causes an enhancement in the heat transfer, while the reverse is true about the remaining
performance aspects. In addition, it was found that the irreversibility due to flow friction intensifies by boosting
either Re or φ. Moreover, the outcomes revealed that the heat transfer is the main source of irreversibility in the
flow of hybrid nanofluid (NF) inside a sinusoidal hairpin heat-exchanger. Furthermore, it was reported boosting
the amplitude results in a decrease in the performance index of the heat-exchanger.