Flow rate coefficient in jap weir single-cycle by CFD

Subject Areas : hydraulic structures

Farhad  Misaghi ¹ (Assistant Professor, Department of Water Engineering ,University of Zanjan, Iran)
Alireza  Seddigh ² (Ms.c Hydraulic Structures, Shahid Chamran University, Ahvaz.)
AmirHossein  Amani ³ (Ms.c Irrigation and Drainage, University of Zanjan.)

Received: 2019-04-15 Accepted : 2021-05-19 Published : 2021-02-19

Keywords: Fluent software, Jap weir single cycle, discharge coefficient flow, turbulence models,

Abstract :

Labyrinth weir are a kind of multi-dimensional weirs that cause passing flow increment with two dimensions. This kind has more effective length than usual sharp tip weirs. In this regard, they can pass more flow than usual weirs for channel with similar width and height. In this study, effective geometrical parameters on single cycle labyrinth weir flow coefficient are measured by means of FLUENT software in three-dimensional way. To model turmoil, k-Ɛ model RNG method and to position free surface profile, VOF method are used. The results of numerical models are compared with those of rectangular weirs with same width. The results for specific H/P show that vertex angle increases with flow coefficient increase and rectangular weir performance of same width is less than single cycle labyrinth weirs, since in same width channel the interference of abscission blades is more severe than single cycle labyrinth weir and such an interference in vertex causes the flow coefficient decrease comparing with single cycle labyrinth weir. Moreover, single cycle labyrinth weir in less hydraulic loads has appropriate performance and ascending trend of flow coefficient.