PERIODICALLY DEVELOPED FLOW AND HEAT-TRANSFER IN A RIBBED DUCT

Periodic fully developed flow and heat transfer results for a ribbed duct were obtained experimentally and numerically, using the nonlinear and standard k-epsilon turbulence models. Predicted recirculation lengths and maximum Nusselt number locations agreed well with the measured values. Both models performed poorly in the separated region just behind the ribs, where the Reynolds stresses were grossly underpredicted, the flow temperatures were overpredicted, and the mean velocity magnitudes were generally underpredicted. The local Nusselt numbers were underpredicted by both models. The nonlinear model predicted more realistic Reynolds stresses in the core flow region immediately above the ribs than the standard k-epsilon model.