عنوان مقاله [English]
نویسندگان [English]چکیده [English]
In this study the controlling of density current by obstacle and roughness has been investigated. Experiments were carried out in a flume with length of 780 cm with 3 variable lengths of insertion roughness (0.5, 1 and 1.5 m) in upstream, downstream, and two sides of obstacle, and 3 heights of roughness (0.5, 1 and 1.5 cm) for each setting. The height of obstacle was considered equal to the height of density current body. Also two concentrations of density current, 10 g/L () and 20 g/L () and two bed slopes, 0% and 2.5% were considered. A series of experiments was performed without using roughness. The results indicated that using roughness with obstacle had significant impact on the controlling of density current. So that without using roughness and just by using an obstacle with the height equal to density current body in the same concentrations and bed slopes, about 31% of density current was blocked. Whereas by using roughness with obstacle in some conditions 100% blocking of density current was obtained. Insertion of roughness in upstream of obstacle had relatively more impact (about 11%) on the controlling of density current as compared with the condition of roughness insertion in downstream of obstacle.