Comparison of DSMC and experimental results of H₂O supersonic condensed jets

In this work we use the direct simulation Monte Carlo-Bhatnagar-Gross-Krook (DSMCBGK) condensation method to simulate water homogeneous condensation in free expanding jets at stagnation pressures of 12 to 1000 mbar. When condensation starts to occur at the stagnation pressure of 96 mbar, as the stagnation pressure increases, the degree of condensation also increases which causes the rotational temperature to increase instead to decrease. We compare with the simulated gas and cluster number densities, cluster size for different stagnation pressures along the plume centerline. The simulated rotational temperature profiles agree well with measurements. We also perfomed an MD simulation of water condensation in a one-dimensional free expansion. The expansion was found to follow the one-dimensional insentropic expansion theory. A larger cluster of average size 21 was tracked down through time, and calculation of its average internal temperature as well as comparison of its radial distribution functions with values measured for solid amorphous ice clusters lead to believe this cluster was in the solid rather than liquid form.