Transient Mixed Flow Modeling in Closed Conduits: A Case Study of Water Tunnel of Golab

Document Type : Research Paper


1 Senior Engineer at Lar Consulting Engineers Co

2 Assistant Professor, Civil Engineering Department, Iran University of Science and Technology

3 Associate Professor, Civil Engineering Department, Amir Kabir University of Technology

4 Senior Engineer at Lar Consulting Engineers Co.


Transient mixed flow occurs under particular conditions in closed conduits, in which both free-surface and pressurized flow come into existence simultaneously. Depending on the origin of the mixed flow, systems experiencing this phenomenon may encounter several problems. Successful simulation of mixed flows is, therefore, necessary to predict and overcome the encountered problems. Different methods are suggested for the simulation of the mixed flows. In this research, transient mixed flow in closed conduits has been analyzed by slot method. The model is further used for the prediction of transient mixed flow in a real-world pipeline system. The results are then used for devising some operational guidelines.


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