Considering four various forms of baffle (plane, trapezoidal, triangular, and isosceles) with sixteen baffle configurations, numerical simulations of steady, incompressible turbulent air hydrothermal phenomena have been studied in a rectangular microchannel, which has a key role in modeling heat exchangers. The governing equations have been solved using the finite volume method and employing the SIMPLE algorithm. To study the turbulence phenomenon, the SST k− ω turbulence model has been used. All the forms of channel, flow structure, normalized velocity profile, normalized skin friction coefficient, normalized friction factor, local, average Nusselt number, and thermal enhancement factor have also been studied at different Reynolds numbers. Among all the baffles, it has been found that trapezoidal-triangular baffles provide the highest Nusselt number, and triangular-isosceles baffles provide the lowest thermal enhancement factor.