Session3: Environmental Hydraulics
Title: DO RECOVERY PROCESS IN A SQUARE EMBAYMENT CONNECTED TO AN OPEN- CHANNEL FLOW
Michio Sanjou, Takaaki Okamoto
This study highlights a DO recovery process in embayment connected to a straight main-channel. Our field survey results in that the DO is larger in opened condition to the mainstream than that closed condition without no mass / momentum exchanges with the mainstream. Hence, the mass exchange between the mainstream and the embayment is decided by the embayment opening. To reveal the relation between DO recovery and embayment opening, we conducted laboratory experiments to measure time-variation of the DO value and horizontal velocity vectors in the model embayment. Finally, we proposed a prediction formula of the recovery time related to reaeration through free-surface and DO supply from main-channel.