Homogeneous Condensation of Nitrogen in Hypersonic Wind Tunnels: A Semi-Empirical Model

摘要

A simplified density functional theory (DFT) is utilized to model nanoscale nitrogen droplets formed by homogeneous nucleation. The single unknown constant of the model is found using planar surface tension values and modern nucleation rate measurements from available literature. Resulting values for the free energy barrier, surface tension, and mean density of critical droplets are used in nucleation and droplet growth rate models to evaluate the condensation process in an axisymmetric Mach 10 nozzle. Good agreement is found between this semi-empirical model and published values, with a maximum deviation of 3.5 K in static temperature at condensation onset.