Modeling the effect of concrete block angles on hydraulic jump length and conjugate depths in the stilling basin (USBR III)

One of the common methods for dissipating kinetic energy of the stream downstream is the aqueous structures of concrete blocks in the stilling basin. Parameters such as shape, jump length, ratio of secondary depth to primary depth and the amount of energy loss are among the important parameters that have a great impact on the cost of relaxation pond structure. It is rectangular and in each position ۵ positioning angles (α = ۱۰-۵۰) degrees are considered for the blocks, which are obtained to achieve the best simulation mode and turbulence model to describe the turbulence terms, respectively, of the two-phase flow of water and Mixture model and four turbulence models were used. In this study, modeling the effect of concrete block angles along the hydraulic jump and conjugate depths in the stilling basin (USBR III) was performed using ANSYS CFX software. Model Turbulence Model (SST k-ω) we have obtained some results based on the ۵۰ models tested: Increasing the angle of position of the blocks up to ۳۰ degrees in convergent mode reduces the jump length by an average of ۴۰% and reduces the secondary depth ratio it is ۱۰%. Also, according to the depths of the most optimal conjugate, the flow profiles in the stilling basins with angles ۳۰ degrees of convergence and divergence.۱