RANS Based Computational Fluid Dynamics Simulation of Fully Developed Turbulent Newtonian Flow in Concentric Annuli

Abstract

A computational fluid dynamics (CFD) simulation is performed via ansys–CFX for a fully developed turbulent flow in concentric annuli with two radius ratios (R1/R2 = 0.4 and 0.5) at three Reynolds numbers (Re = 8900, 26,600, and 38,700) in terms of the hydraulic diameter D and the bulk velocity Ub. Near-wall turbulence structures close to the inner and outer walls are characterized by analyzing the first-order and second-order statistics. Effects of transverse curvature and the Reynolds number on development of the turbulence structures are emphasized. This study demonstrates the ability to predict the asymmetric features of turbulent flows in annular pipes by using the Reynolds-Averaged Navier–Stokes (RANS) model. Estimation of viscous dissipation in the flow using a RANS model is compared with direct numerical simulation (DNS) results for the first time.