Effects of rotation and swirl on turbulent pipe flow

Abstract

Direct numerical simulation (DNS) has been carried out to study the combined effects of rotation and induced swirl on the fully developed turbulent pipe flow at Reynolds number Reb = 4900, based on the bulk velocity and the pipe diameter. The swirl is induced by a body force in the tangential momentum equation, which produces a tangential velocity field in the near wall region. Results from a single swirl along with five different strengths of rotation are considered. The serial finite difference DNS code used by Sahoo et al. [1] has been made parallel by using MPI library. The grid used consists of 128 × 96 × 512 grid points in −, r− and z− directions, instead of 65×97×65, used by Sahoo et al. [1]. The effects of rotation and swirl on turbulent structures are investigated in detail.