A turbulent plane offset jet with small offset ratio

Abstract

 Mean velocities and turbulence characteristics of a turbulent plane offset jet with a small offset ratio of 2.125 have been studied using laser Doppler anemometry (LDA). Static pressure measurements highlight the importance of side plates in enhancing two-dimensionality of the jet. The spatial distributions of turbulence intensities and Reynolds shear stress show a high turbulence recirculating flow region close to the nozzle plate between the jet and the offset plate. The LDA results have been used to examine the capability of three different turbulence models (i.e. k–ɛ, RNG and Reynolds stress) in predicting the velocity field of this jet. While all three models are able to predict qualitatively the recirculation, converging and reattachment regions observed experimentally, the standard k–ɛ turbulence model predicts a reattachment length that best agrees with the experimentally determined value.