We numerically analyze the hydro-thermal characteristics of the flow of incompressible fluids in a triangular corrugated duct using finite element method (FEM). The outcomes in terms of streamlines, temperature contours and average Nusselt number ( \(\overline{Nu }\) ) are depicted for different Prandtl number (Pr) extending from 0.72 to 100 and Reynolds number (Re) extending from 5 to 200 at constant amplitude and wavelength of the duct. In the corrugated region, there is a formation of recirculation zones, the size of which is increased with Re. The value of \(\overline{Nu }\) increases with Pr and the rate of increase is more for higher Re and Pr. The rate of heat transfer compared to an equivalent plane duct is quantified by enhancement ratio (ER) which follows a non-monotonic trend with Pr at a lower value of Re and a monotonic variation at Re = 200. The combined rate of heat transfer and pressure drop variations are compared to those of straight channel in terms of performance factor (PF). At higher Re, PF increases with Pr, while at the lower value of Re, the behavior with Pr is non-monotonic.