Experimental Study of the Downstream Scouring Pattern of Submerged Jets in Single and Compound Arrangements

Subject Areas : Subjects

dena bidar ¹ (دانشجوی کارشناسی ارشد مهندسی رودخانه دانشگاه صنعتی خاتم الانبیاء بهبهان)
seyed amin asghari pari ² (دانشیار دانشگاه صنعتی خاتم الانبیاء بهبهان)
seyed mohsen sajadi ³ (استادیار دانشگاه شهید چمران اهواز)

Received: 2015-05-22 Accepted : 2017-10-20 Published : 2018-04-21

Keywords: densimetric Froude number, Keywords: Scouring of submerged jet, angle, arrayed arrangement, single arrangement,

Abstract :

The objective of this experiment, which was performed in the flume of the KWPA Sedimentation Laboratory, was to study the scour patterns formed by the submerged jets of different shapes arranged singly or arrayed at different spacing and angles with different discharges. The experimental study consisted of 4 scenarios: The shape of jets in the single and arrays arrangement and the spacing and angles in the arrayed setup. All effective parameters on submerged jets performance were studied and the dimensionless relationships were derived according to the dimensional analysis. Then dimensions of scour patterns in downstream of jets were recorded. The results indicated that the best performance for scour development was related to diamond shaped jet, in the single arrangement; however, the shape of jet was not an effective parameter in the arrayed arrangements. Furthermore by increasing the horizontal distances between the arrayed jets, all of the scour dimensions (except width) were decreased. Additionally, decreasing the angles between the crossing arrayed jets caused a significant reduction in the scour pattern dimensions.
Keywords: Scouring of submerged jet, densimetric Froude number, angle, arrayed arrangement, single arrangement

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