Author(s): Serhat Kucukali
Linked Author(s): Serhat Kucukali
Keywords: Dissolved oxygen; Aeration; Boulder; Stream restoration
Abstract: In this experimental study, boulder-flow interaction associated with the self-aeration process has been investigated in a 0. 5 m wide flume. Experiments were performed with three different boulder arrangements (BA) and four different relative submergences of boulder (s) with the Reynolds number ranging from 5*103 to 5*104. It is shown that the presence of boulder (s) in a flow-field directly affects the local dissolved oxygen (DO) variations, by generating flow acceleration, hydraulic jump and plunging jet depending on the boulder arrangement, size and flow condition. Back edge of the boulder (s), where current is nonexistent or very weak (which creates a refuge from the flow to the aquatic biota in the nature), are characterized by less amount of DO levels relative to other local regions. When the boulder submergence ratio exceeded 1, maximum local aeration efficiency (Emax) tended to decrease rapidly. Furthermore, maximum local aeration efficiency and blockage ratio of the boulder (s) related positively and described by a power function.
Year: 2005