The effect of rib shape on the behavior of laminar flow of oil/MWCNT nanofluid in a rectangular microchannel

in this research, the laminar and forced flow and heat transfer of oil/multi-walled carbon nanotubes nanofluid in a microchannel have been numerically investigated. the studied geometrics is a two-dimensional rectangular microchannel with the proportion of length to height of 150 (l/d = 150). the purpose of this research is to investigate the effect of using rectangular, oval, parabolic, triangular and trapezoidal rib shapes on behavior and heat transfer of nanofluid flow in the rectangular microchannel. this research has been simulated in reynolds numbers of 1, 10, 50 and 100 and volume fractions of 0, 2 and 4% of nanoparticles by using finite volume method. the results of this research indicate that the existence of ribs enhances the friction factor and nusselt number, significantly. also, the shape of rib is one of the most important factors for determining the behavior and heat transfer of cooling fluid flows. among the investigated rib shapes, the parabolic rib, comparing to the augmentation of friction factor, has the best proportion of nusselt number enhancement.