Numerical Analysis of Turbulent Flow in a 90-Degree Bend Pipe with a Half-Trip

Abstract

Numerical analysis has been performed for turbulent flow in a 90-degree bend pipe with half-tip ribs by using an algebraic Reynolds stress model and boundary fitted coordinate system. Calculated results are compared with the experiment in order to confirm the validity of the presented model and clarify the mechanism of drag reduction. It has been found that the calculation can reproduce reasonably the measured velocity profiles including secondary flow vectors. Besides, calculated results suggest that drag reduction must be caused by the secondary flow of the second kind which is produced by anisotropic turbulence through half-trip rib.