Numerical simulation of heat transfer and resistance pattern in channels with different ribs

Standard k-ε turbulence model and enhanced wall treatment were employed to investigate the flow-field, heat transfer and resistance coefficient in two-dimensional channels with different ribs (rectangular/trapezoidal/triangular/semi-circular cross section). The inflow Reynolds number varied from 5000 to 10000. All the ribs were uniformly spaced in channels with a pitch-to-height ratio of 4, a base width-to-height ratio of 2. The results indicate that local Nusselt numbers of the heated wall vary periodically along the flow direction for all channels. For larger Reynolds number, the resistance coefficient and average Nusselt number in the channel with triangular ribs are the largest ones compared with others. The channel with semi-circular ribs has the smallest resistance coefficient while the channel with rectangular ribs has the smallest average Nusselt number. The results presented in this paper can be a reference for engineering design.