Structure of open-channel flows through an array of square cylinders
Résumé
The impact of obstacles on the hydrodynamic flow structure is of major interest since such flows are representative of flooded urban areas. This study focuses on a pattern depicting a single-family home and garden area, as found in recent suburban development. The purpose herein is to analyze the evolution of the velocity distribution for a densely built area as well as for emerged to slightly submerged situations, which represent various flood situations ranging from commonplace to extreme. Free-surface flows through an in-line distribution of square cylinders were investigated in a laboratory flume, in the aim of assessing the effect of relative submergence on the flow structure within the cylinder array. The results show that the lines of square cylinders channelize the flow. Moreover, the submerged case generated similar flow characteristics below the top of the cylinders, which drastically changed once the water flowed above the square cylinder level.