Numerical investigation of supersonic jet using a two-fluid turbulence model

In the present work, numerical simulation of an axisymmetric jet at a Mach number of 1.63 under temperature-matched conditions was performed using an improved two-fluid turbulence model. The proposed model includes an additional transport equation for the relative molar velocity, which enables a more accurate representation of Reynolds stress anisotropy, compressibility effects, and structural changes in high-speed shear layers. To evaluate its predictive capabilities, the model was validated against NASA benchmark experimental data. Distributions of axial velocity and radial profiles of turbulent characteristics were obtained in the cross-sections x/D = 2–16. The results demonstrate excellent agreement with experimental measurements, including accurate prediction of jet core decay, mixing layer growth, and turbulence suppression at high Mach numbers. Comparison with conventional RANS approaches shows that the developed model provides superior performance in descri-bing anisotropic turbulence and compressible flow dynamics. The obtained results confirm the effectiveness of the two-fluid model for simulating high-speed jet flows and its applicability in aerospace engineering, nozzle gas-dynamic calculations, and aeroacoustic prediction problems.