Accuracy in evaluating heat transfer coefficient by RANS CFD simulations in a rectangular channel with high aspect ratio - Part 2: channel with ribbed walls

Abstract In this paper, a Computational Fluid-Dynamics (CFD) analysis on heat transfer characteristic using Reynolds Averaged Navier-Stokes (RANS) equations rectangular channel with ribbed surfaces is presented. Several numerical simulations have been carried out convective of an air flow through 1:10 aspect ratio, 120 mm wide, 840 long, 90° ribs. Ribs square cross section 4 side and three different values dimensionless pitch, namely, 10, 20 40. Results global coefficient, i.e., averaged over the whole channel, compared to experimental data obtained in same geometry boundary conditions. Agreement between discussed for pitches considered. As expected, comparisons show decreasing reliability increasing complexity. The aim work find suitable configuration CFD model RANS that will permit authors apply it range pitches.