抄録
A free-surface velocity divergence is highlighted as a key parameter of the gas transfer, because the accurate divergence value can be obtained with the advances of the PIV technique. However there still remain uncertainties about the relation between the free-surface divergence and the gas transfer velocity in open-channel flows such as natural rivers. In this study, we conducted a horizontal free-surface PIV in laboratory flume together with DO measurements. A new physical model of gas transfer parameterized by the free-surface velocity divergence is presented and this validity is examined intensively by comparison with present measured data.
