LAUSR

Abstract Expansion of the condensing copper vapor into vacuum from a high-temperature source is studied for transient and near-continuum flow regimes within the direct simulation Monte Carlo method. Kinetic approach, which assumes cluster formation/decay description via monomer-cluster reactions with corresponding cross-sections, is employed. Clusters observed in calculations are of subnanoscale size. Impact of condensation on gas-dynamic jet parameters is significant for the regimes for which the terminal mole cluster fraction in the jet exceeds 1%. For such regimes both velocities and translation temperatures of clusters and monomers, are close to each other, while cluster internal temperature is higher than the translational vapor temperature. Characteristic clusterization modes are revealed depending on the intensity of the cluster formation process in the source domain and in the jet. Obtained values of the internal dimer temperature and average cluster size in the jet far field are in a good agreement with the experimental data and known scaling laws.