Re-Transport Mechanisms Of Fallen Pollen By Surface-Creep And Saltation
The cedar pollinosis is a very serious problem in Japan. The prevalence of this pollinosis is considered more than 20% among the Japanese. In the point of avoiding pollen exposure, it is important to clarify the pollen transport mechanisms. In particular, in urban areas of Japan, the house has been built to be nearly in contact with another. If the fallen pollen on the roof is re-transported and falls down to the lower level, the exposure amount will increase drastically. Accordingly, in this study, we focus on the re-transport mechanisms of the fallen pollen on surfaces and carried out the wind tunnel experiments by using test particles to clarify the pollen exposure from roofs. The test particles are carried by the wind, and move (creep) along or jump (saltate) repeatedly on the surface. Consequently, we discuss the followings in this paper: the optical measurement of surface-creep and saltation behavior of the test particles, the generality of the flow field in this study and the possible conditions of re-transport from a surface.
Keywords- Flow Visualization, Multi-phase Flow, Particle Tracking Velocimetry, Pollen Transportation