“…Flows where the downstream water level affects the upstream water level and the downstream water level is higher than the gate opening are expressed as submerged flow. In the literature, there are many studies examining the flow characteristics for free flow (Silva and Rijo, 2017;Ferro, 2018;Petrila, 2002;Hoseini and Vatankhah, 2021;Dou et al, 2020) and submerged flow (Vaheddoost et al, 2021;Bijankhan et al, 2017;Sauida, 2014;Shayan and Farhoudi, 2013;Shaddehi and Bijankhan, 2020) after the gate and investigating the flow around the weir in various geometries (Haghiabi et al, 2021;Hu et al, 2018;Zounemat-Kermani and Mahdavi-Meymand, 2019;Zhang et al, 2018;Tullis, 2011). However, the number of studies is limited for situations where the gate and weir structure are used sequentially in channels that are not rectangular.…”