Numerical Study of Swirling Jet Streams Based on Modern Turbulence Models

This article examines a swirling jet based on a two-fluid turbulence model. This task, despite its simplicity, is quite a difficult task for many turbulence models. Because anisotropic turbulence is observed in swirling flows. Therefore, many modern RANS models are not able to describe such flows even qualitatively. The two-fluid model used in this work has been developed recently. Pioneering work shows that the basis for constructing this model is the possibility of representing a turbulent flow as a heterogeneous mixture of two liquids. Approach was proposed by Spaulding. The idea of the approach is to represent turbulence as the interpenetrating motion of two fluids, with the pulsating nature of the turbulent flow being caused by the relative moverment of them. For each fluid, it's own equation of motion is written, which leads to a closed system of equations. These studies also show that the developed two-fluid model is able to adequately describe complex anisotropic turbulence. To numerically implement the equations of a turbulent axisymmetric swirling jet, a uniform staggered calculation grid and a control volume method were used, and velocity correction was carried out using a simple method. The numerical results obtained are compared with experimental data from the ERCOFTAC database. It is shown that the results of the two-fluid model, despite the use of a rather rough computational grid, are in satisfactory agreement with experimental data.