This paper presents the numerical study of forced convective heat transfer with the help of nanofluids for various duct cross sections, namely circular, square, triangular, serpentine and elliptical are taken into consideration. The CFD analysis is carried out in a turbulent regime with Reynolds number (Re) in the range of 3000−9000 and a volume fraction of 1%. Nanofluids have shown considerable augmentation in the base fluid’s heat transfer and thermal conductivity. A single-phase model predicts the Nusselt number (Nu), Nu enhancement factor, friction factor and thermohydraulic performance factor. The highest Nusselt number and friction factor enhancement were noticed for similar hydraulic diameter and heat input for serpentine geometry. Due to the higher friction factor in the serpentine duct, the highest value of THPP was reported for elliptical geometry.