抄録
In case of the high humidity, mist particles occur near the cooling surface located in the moist air, so that the vapor concentration decreases and the temperature increase due to phase change of vapor i.e. condensation. Therefore the mist generation affects on both heat and mass transfer. In this present study, the diameter and velocity of the mist particles were measured simultaneously by using PDPA. The mist layer thickness was also optically measured. In addition, a set of boundary layer equations -continuity, momentum, energy and diffusion equation- was solved with satisfaction of the saturated condition, and were obtained analytically temperature and vapor concentration profile. As a result, the mist layer thickness is represented as a function of the Grashof number. And, the velocity of mist particle obtained experimentally agrees wel1 with the analytical velocity of natural convection without the mist formation. The mist particles with a large diameter exist near the frost surface, and the small mist particles distributes apart from the frost surface.
