Numerical Investigation of Turbulence Models for Free Jet Flow

Abstract

The turbulent jets with swirl are of particularly significant and practical interest in various fields of industry. The present numerical study concerns the comparison between three models of turbulence for the forecast of a turbulent free axi-symmetric jet with turbulence and his development. The software used was CFD code Fluent with his three turbulence models namely k-, k- and RSM. This different turbulence models are tested to better simulate and view the effectiveness of models in the description of the jet behaviour. The parameters of flow examined are the velocity profile of jet at Reynolds number of 22000. Comparisons between numerical predictions and experimental measurements taken from the technical literature for the case of natural jet development show that the numerical techniques of Computational Fluid Dynamics are an important tool for studying the jet’s behaviour. The results indicate that the RSM models is higher than the k- and k- models when looking at changes in velocity profile behaviour towards experimental profile, the k- model can be used for predicting re-circulating flows if we are interested in global settings only. The prediction obtained by k- model is far from experimental results. It is misadvised to use k- model for the jets analysis. The better numerical results were obtained by CFD code CFX, where results are in good agreement with the experimental results.