抄録
This study is concerned with the discrepancies between the results of experimental measurements and molecular dynamics(MD) studies on the condensation coefficient of water. We consider that the presence of a noncondensing gas may increase the interface resistance and reduce the experimental condensation coefficient. One-dimensional condensing flow of water vapor has been analyzed by the direct simulation Monte Carlo(DSMC) method in the presence of a noncondensing gas. The results show that the condensing flow causes an accumulation of the noncondensing gas in the vicinity of the liquid surface that increases resistance and reduces condensation heat transfer rate. Even if the concentration of the noncondensing gas is low in the bulk phase, the noncondensing gas accumulates at high concentrations at the interface. This indicates the possibility that the low experimental condensation coefficients may be due to the existence of noncondensable gases.
