Hydraulic characteristics of the hydraulic jump on the stepped, reverse slope and roughness

In this research, the simultaneous effect of the stepped, reverse slope and roughness on hydraulic jumping characteristics at Froude number 4.98 has been investigated by using numerical simulation with Flow-3D software. Also, some different tabulated models such as RNG and k-epsilon have been employed to simulate the flow aft her the sluice gate. Numerical results indicated that the results of the vertical velocity profiles of the RNG turbulence model have more agreement with experimental tests due to different hydraulic conditions. Comparisons among results of the 3D numerical results and experimental tests like water surface profile, velocity profile, sequent depth ratio, rolling length and hydraulic jump length and energy loss ratio illustrated that the developed numerical model can simulate the flow in free flow. Finally, extracted hydraulic parameters from numerical simulation indicated that the impacts of the reverse slope and initial negative step of the bed have the significant impact on the increment of secondary depths of the hydraulic jump at the downstream of the sluice gate with 23.2 and 28.19%, respectively. Furthermore, increment of the roughness causes the decrement of the secondary depth by average of 9.81%. Also, the results of the energy loss indicated that removing the initial negative step can increase the energy loss; however, presence and increment of the reverse slope and roughness can increase the energy loss which indicate that the roughness and reverse slope can be employed as the countermeasures to control the hydraulic jump at the downstream of the sluice gate.