One of the most concerning issues for researchers is to predict the shape and dimensions of the scour pit near
hydraulic structures such as the base of bridges, weirs, valves and stilling basins due to both financial and human
hazards induced by destruction of the structure. As the scour issue has its own complexity in relation to the
multiplicity of effecting factors on it, in this study therefore, the results of laboratory analysis of local scour due to
submerged horizontal jets were compared with numerical simulation results from Flow-3D three-dimensional model
to test the potency of the numerical model. As a result, the model is proposed in place of the experimental model
which has its own drawbacks and high costs. In this study, we measure maximum scour depth in relative equilibrium
in 2 states and 6 test modes with different valve openings and tail water depth per different discharges. Comparison
of the results indicates about 11% error for Flow-3D numerical model in relation to the experimental model which by
considering the complexity of scour and deposition phenomena, is considered a good result.