Comparison of turbulence models in simulating axisymmetric jet flow

Abstract

The present work is a comparison of various turbulence models available in ANSYS-Fluent in simulating an axisymmetric jet flow. A large domain is chosen for simulation of the jet flow with an intention to avoid errors due to the computational boundaries. The simulations are carried out at a fixed Reynolds number for facilitating comparisons. This work considers various first-order closure models such as standard k-epsilon model, standard k-omega model, RNG k-epsilon, Realizable variants of k-epsilon model, SST k-omega model, and a second-order closure model namely Reynolds stress model. The simulated results are compared with reference literature to understand the applicability of models using various parameters such as inverse mean axial velocity decay, turbulence intensity, turbulent kinetic energy, and streamlines. Large variations are found in all the parameters between first and second-order turbulence closure models. The streamlines also show reverse flow patterns near the nozzle for second order turbulence model. The first-order closure models are found to be better than the second-order closure models in predicting the flow field of axisymmetric jets.