LES Analysis of Gas Flow and Mixing Process in an Unsteady Jet

The flow and mixing process of unsteady jets are fundamentally analyzed by large eddy simulations. The effects of nozzle velocity and turbulence intensity on the turbulent eddy structure and mixing process between the nozzle fluid and ambient fluid were investigated. The results show that a toroidal-shaped vortex, which emerges around the jet tip, primarily accelerates the entraining flow. Furthermore, the difference of jet density affects the shape of toroidal vortex formed near jet tip and the air entrainment. Jet with lower density is less entrained and suppresses turbulent mixing.