Numerical simulation of the interactions among multiple turbulent swirling jets mounted in unbalanced positions

• The interaction of multiple swirling jets mounted with unbalanced positions has been investigated.
• Standard, RNG k−ɛk−ɛ and Reynolds Stress Model (RSM) turbulence models have been used for the numerical computations.
• The RSM produces fairly accurate results.
• The interaction between swirling jets induces a redistribution of temperature in the mixing zone.
• The optimization of key parameters greatly improves the quality of the thermal homogenization.

In this study, we numerically examined the interactions among multiple swirling jets mounted in unbalanced positions. The formulation was based on the Reynolds average Navier–Stokes equations. In this study, turbulence was modeled using different turbulence models, i.e., k−ɛk−ɛ standard, renormalization group, and Reynolds stress model (RSM) to make comparisons. This study was conducted under uniform thermal conditions for each configuration. The working fluid was the air, the Reynolds number was fixed at Re0=3.104Re0=3.104, and the swirl number calculated from the measured velocity data was 1.33. We performed this study using the finite-volume FLUENT computational fluid dynamics solver. For most of the configurations analyzed, the results obtained using the RSM model agreed better with the experimental data compared with the standard turbulence model. The analysis of the flow features with moderate mesh refinement showed that the interactions between the swirling jets redistributed the temperature in the mixing zone as well as promoting the radial spread of the resultant jet. As expected, the development of the central jet improved thermal homogenization. More importantly, our results showed that changing the position between the central and peripheral jets greatly affected the quality of the thermal homogenization of the atmosphere.