Surface Currents Effect in the Explicit Algebraic Reynolds Stress Turbulence Model for Simulation of Lateral Buoyant Jets in Cross-Flow

The interaction of turbulent shear flow with the free surface generates a thin vertical zone near the surface with a large outward velocity, known as surface current. In this study, numerical modeling of surface currents in laterally discharged buoyant surface jets in crossflow is investigated. The governing equations comprise the three-dimensional Unsteady Reynolds-Averaged Navier–Stokes (URANS) equations, closed by different linear and nonlinear turbulence models. It is found that the effect of turbulence models on improving free surface results is insufficient. A new term is proposed in the turbulence model’s Reynolds stress tensor to depict the surface current effect. The thermal scalar flux was calculated using the transfer equation with a free surface adjustment term. All existing coefficients in the newly defined terms and thermal scalar fluxes are determined by comparing numerical results with previous laboratory data.