Effects of superheated steam on non-equilibrium condensation in ejector primary nozzle

• Wet steam model for non-equilibrium condensation in Laval nozzle was built.
• Validation of simulation data with experiment results.
• Effects of superheated steam on condensation in nozzle were fully studied.
• Increase of superheat attenuates condensation shock and enhances steam stability.

In order to reduce the non-equilibrium condensation occurring in ejector primary nozzle, wet steam model was adopted to investigate the relationship between steam superheated level and non-equilibrium condensation within ejector primary nozzle. Simulation data of axial static pressure along primary nozzles were validated with experimental data reported in literature. The non-equilibrium condensation process from homogeneous nucleation to droplet growth stage and the resulting products were carefully studied. Moreover, six inlet superheated levels from 5 K to 30 K with the increment of 5 K were compared, and simulation results showed that the increase of superheated level from 5 K to 30 K causes 40.22% delay in the location and 43.92% reduction in the intensity of the condensation shock. Furthermore, there is about 24.30% liquid mass fraction decrease when the superheated level raises to 30 K and total entropy generation increases slowly with the increase of superheated level.