Numerical research on nitrogen spontaneous condensation in converging-diverging nozzle

Assuming a homogeneous flow without velocity slip between gas and liquid phases, 2-D numerical simulation for predicting nitrogen expansion flow with spontaneous condensation in a converging-diverging nozzle is accomplished via the non-equilibrium model of CFX. The mass transfer between two phases is calculated with the classical nucleation model and the standard Redlich Kwong state equation. The magnitude of nucleation rate, pressure and condensate mass fraction distributions, and condensation onset are comparatively analyzed to verify the validation of the model. Compared with the adiabatic expansion without condensation, the flow is heated by the latent heat and thermal conductivity between gas and liquid phases to heighten pressure and lower Mach number. A comparison between equilibrium condensation model and non-equilibrium condensation model shows better prediction of the latter for nitrogen expansion with spontaneous condensation. ©, 2015, Xi'an Jiaotong University. All right reserved.