Simulation of turbulent flow and forced convection in a triangular duct with internal ribbed surfaces

A three-dimensional problem of fully developed turbulent flow through an equilateral triangular duct with internal ribbed surfaces has been simulated numerically through two two-dimensional approaches: turbulent forced convection between two parallel plates with ribbed bottom surface and that in an equilateral triangular duct with smooth internal surfaces. Effects of the complicated geometry on the turbulent forced convection, as well as the formation of the secondary flows around the ribs and in the triangular duct's corners, are analyzed in detail. Comparisons between the calculated and experimental results have been carried out and it has been found that the geometry effect from the attached uniformly spaced ribs on the triangular duct's thermal performance is more significant than that from the duct's corners.