2010 年 76 巻 772 号 p. 2075-2082
Three-dimensional direct numerical simulation (DNS) is applied to a gas-liquid two-phase flow with a non-mobile wavy gas-liquid interface, and the turbulence structure in boundary layers on both gas and liquid sides and the scalar transfer mechanism across the gas-liquid interface are investigated. The results show that the scalar transfer across the non-mobile wavy gas-liquid interface is mainly controlled by the longitudinal vortices related to bursting motions on the liquid side, whose mechanism is similar to those across the flat and realistic wind-driven gas-liquid interfaces. However, since the scalar transfer is strongly affected by the fixed interface configuration, the low-scalar-flux streaks observed in the cases of the flat and realistic wind-driven gas-liquid interfaces do not clearly appear. This means that in order to precisely predict the scalar transfer rate across the realistic wind-driven gas-liquid interface, the non-mobile wavy gas-liquid interface is not suitable to be employed.