Numerical simulation of energy loss in the chute with submerge cubic obstacle

Authors

1 M.Sc. Student, Department of Water Sciences Engineering, Shahid Chamran University, Ahvaz, Iran.

2 Professor of faculty of Water Science Engineering of Ahvaz Chamran University

3 AssistantProfessor, Water Sciences Engineering Faculty, Shahid Chamran University, Ahvaz, Iran.

Abstract

In this study, energy loss in chutes with cubic submerged obstacles is investigated. The advantages of this method over previous methods such as stepped spillway are the less risk of cavitation. FLUENT finite volume software was used for numerical computation which employs finite elements method to solve flow equations. The flow was considered turbulent and fluid was considered incompressible. The turbulent model of  was used in this study. In general, for the range of discharges in this study, the energy loss varies from 11% in 1:4 slopes to 66% in 1:5 ones for witness models. The results of energy loss in blocked-bed models showed a downward and linear trend with a relatively steep slope. However, the “relative energy loss” was shown to be the most in 1:4 slope and the least in 1:5 slope. Moreover, the energy loss relative to upstream energy varies from 83% in models with 1:4 slope to 45% in the blocked-bed models with 1:8 slopes. Furthermore, energy loss in blocked-bed models has been increased from 18 to 41 percent in comparison to the control models. At last, using multivariate regression, some equations was extracted to estimate energy loss.

Keywords

References

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