Review of Reduced-Order Models for Homogeneous CO2 Nucleation in Supersonic and Hypersonic Expansion Flows

Several classical and non-classical reduced-order nucleation rate models are presented and compared to experimental values for the homogeneous nucleation rate of CO2
in supersonic nozzles. The most accurate models are identified and are used in simulations of a condensing supersonic expansion flow. Experimental results for the condensation onset point of CO2
in a variety of expansion facilities are presented and compared to simulations and to new data acquired at the SBR-50 facility at the University of Notre Dame.