RESUMO

The present work is an experimental study of the evolution of swirl with the well defined characteristic of solid-body rotation introduced at an initial station into the turbulent flow in a pipe. The swirl is generated by a specially designed device based on the principle of a rotating honeycomb so that the experimentally realized flow exhibits the characteristic of solid-body rotation over essentially the whole pipe cross section. The evolution of the various components of the mean velocity vector and Reynolds stress tensor in this flow is measured by 3-D LDV employing the refractive index matching technique at rotation numbers of up to one. The results draw attention to some outstanding features of the turbulence in this flow.