Influence of gate plate slope on hydraulic characteristics of sluice gates

Subject Areas : Farm water management with the aim of improving irrigation management indicators

Rasoul Ilkhanipour Zeynali ¹ , Sayyed Habib Mousavi Jahromi ² , Sayyed Mahmoud Kashefipour Dezfouli ³ , Manouchehr Fathi Moghadam ⁴

1 - Ph.D Student, Department of Water Structures, Faculty of Water Science Engineering, Shahid Chamran University, Ahwaz, Iran
2 - Professor, Department of Water Structures, Faculty of Water Science Engineering, Shahid Chamran University, Ahwaz, Iran
3 - Professor, Department of Water Structures, Faculty of Water Science Engineering, Shahid Chamran University, Ahwaz, Iran
4 - Professor, Department of Water Structures, Faculty of Water Science Engineering, Shahid Chamran University, Ahwaz, Iran

Received: 2015-04-11 Accepted : 2015-09-21 Published : 2015-09-22

Keywords: contraction coefficient, radial gate, sluice gate slope, top hinged flap gate,

Abstract :

Gate plate slope has an important role on hydraulic characteristics of sluice gates. In the previous studies, the influence of gate plate slope on hydraulic characteristics of sluice gates has not investigated theoretically. By applying the results of this theoretical study, the theoretical relations for discharge characteristics of sluice gates will be obtained depend on the gate plate slope. These theoretical and simple relations can be used to radial and top hinged flap gates, instead of long and complicated empirical and dimensional analyses-based equations. In this order, Euler’s equation was used to relate the specific energy of inclined sluice gate with specific energy of vertical sluice gate in rectangular channels under free orifice-flow condition. The gate plate slope was considered in the streamwise component of the gravitational acceleration in Euler’s equation. The ratio of inclined to vertical sluice gates specific energies obtained depends on the gate plate slope. The equation allows for the gate plate inclinations into the upstream pool. By applying the relation for specific energies ratio along the surface streamline, the water depths ratio at the vena contracta obtained depends on the gate plate slope with assuming negligible energy loss and approach velocities. Experimental data were used to validate the proposed equation for water depths ratio at the vena contracta, which showed good agreement with the measured values. Also, other equations presented for contraction and discharge coefficients variation with the gate plate slope. The proposed relation for contraction coefficient developed to radial and top hinged flap gates.