Abstract
It has been pointed out that the turbulent structures near a free surface have a close relationship with coherent vortices, and that those characteristics are greatly affected by the presence of the free surface. Furthermore, mass transfer across an air-water interface is a fundamental and very important process in environmental and geophysical problems. Therefore, three different turbulent conditions were considered; namely, bottom shear driven turbulence, wind shear driven turbulence, and combined wind/stream driven turbulences. The aim of this study is to evaluate the relationship between the turbulence structure near the interface and the gas transfer process across the air-water interface. As a results, the mechanism of gas transfer across the air-water interface is well explained by a small-eddy model.
