An experimental study of the effect of baffle blocks distance from a gate on the hydraulic jump length and energy dissipation

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

Mir Mahmood Valinia ¹ , Seyed Ali Ayyoubzadeh ² , Mehdi Yasi ³

1 - Former M.Sc. Student, Department of Water Structures Engineering, University of Tarbiat Modares, Tehran, Iran
2 - Associated Professor, Department of Water Structures Engineering, University of Tarbiat Modares, Tehran, Iran
3 - Associated Professor, Department of Water Engineering, University of Urmia, Urmia, Iran

Received: 2014-02-01 Accepted : 2014-06-07 Published : 2014-06-21

Keywords: energy dissipation, floor block, jump length, sluice gate,

Abstract :

An experimental study was conducted to investigate the effect of blocks distance from the sluice gate on hydraulic jump characteristics. A number of 36 tests in a range of Froude numbers, relative tailwater depths and blocks distances from the gate were considered. Dimensional analysis was used to interpret the results and the effect of each parameter. The obtained results showed that the blocks distance from the gate has negligible influence on energy dissipation and also on relative energy dissipation. Increasing in Froude numbers from 6.4 to 8 resulted in increasing the relative energy dissipation nearly 8%. However, once relative tailwater depths increased from 5.26 to 7.36, the energy dissipation was considerably decreased, i.e. about 34%. Results of energy dissipation efficiency showed that the blocks distance from a gate has no clear effect on this parameter, but it was decreased with increasing Froude number and decreasing relative tailwater depth. Furthermore, the results showed that the relative jump length was increased about 115% when the relative blocks distance increased from 0.18 to 0.54.