Numerical Analysis of Turbulent Flow in a U-Bend with Rectangular Cross Section

Abstract

When using CFD for the designing of fluid equipment, turbulence model is frequently used. However the accuracy of analysis is not sufficient in some cases when complicated flow separation is occurred. Therefore, it is important to select appropriate turbulence model and consider boundary layer development. In this study, we conducted numerical analyses for turbulent flow in a square sectioned U-bend duct in which flow separation is occurred due to strong curvature and tested two turbulence models and two inlet boundary conditions. Then we compared computations and measurements and it was revealed that separation region tended to be overpredicted under uniform inlet flow conditions regardless of turbulence model.