Buoyancy effects on the supersonic steam jet injection into cocurrently and countercurrently flowing water

In this study, the hydrodynamics of the negatively buoyant supersonic steam jet injected into the water has been investigated based on the effects imparted by its density difference with the water in free and confined configurations. In case of both the upward and downward steam’s free injection, the steam jet-water flow has shown a clear deviation from the non-dimensionalized Boussinesq character. However, in the confined injection, the steam jet creates recirculation regions contributing to enhancing mixing with the water. The generation of recirculation regions owes to the existence of the low-pressure regions at the nozzle exit, baroclinic torque and buoyantly influenced flows, which is associated with the density difference between the steam and water and the shear between the two phases. The buoyancy affects the flow domains in a nonuniform manner. It affects the fluctuating quantities marginally in the jet-developing region, and in the middle section, however, its effect is dominant in the steam jet’s tip region.