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A numerical method for liquid-vapor two-phase flows accompanied by condensation/ evaporation is proposed. The phase change model at the vapor-liquid interface, which had been theoretically derived by Sone and Onishi, is coupled with an interface capturing scheme. The model gives the condensation/evaporation rate as boundary conditions. The interface is captured by the volume-of-fluid method associated by the reconstruction scheme, and the scheme to obtain the pressure with consideration for thermodynamics in the vicinity of the interface is employed. These methods are coupled and arranged on the cylindrical coordinate system to appropriately deal with the liquid film flow around a cool cylinder in a natural convection of vapor. The development of a liquid film due to the condensation, the flow in a thin layer and a drop of the distilled liquid are successfully reproduced in our result. The influence of the volumetric conservation is confirmed by comparing the results of condensation case and a non-condensation case. Besides the Nusselt number is in good agreement with a theoretically estimated value.

The suspending particulate matter (PM 2.5 ) is a typical indicator of small particles in the atmosphere. Accordingly in order to monitor the air quality, sampling of PM 2.5 has been widely undertaken over the world, especially in the urban cities. On the other hand, it is known that the sun photometry provides us with the aerosol information, e.g. aerosol optical thickness (AOT), aerosol size information and so on. Simultaneous measurements of PM 2.5 and the AOT have been performed at a NASA/AERONET (Aerosol Robotics Network) site in urban city of Higashi-Osaka in Japan since March 2004, and successfully provided a linear correlation between PM 2.5 and AOT in separately considering with several cases, e.g. usual, anthropogenic aerosols, dust aerosols and so on. This fact suggests that the vertical distribution also should be taken into account separately for each aerosol type. In this work, vertical profiles of atmospheric aerosols are considered based on combination use of photometric data with AERONET, LIDAR (Light Detection and Ranging) measurements and model simulations.

We developed a practical method for the computation of liquid-vapor two-phase flows accompanied by phase change at the interface. In this paper, we propose an intrinsic improvement by introducing a boundary condition at the non-equilibrium interface, which was derived by Sone and Onishi (

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