Simulation of blockage effects on scouring downstream of box culverts under unsteady flow conditions

Numerical Modeling of Downstream Scour in Circular Culverts: Impact of Inlet Blockages and Variable Flow Conditions

“…3 illustrates the boundary conditions, where a specified flow rate is set at the inlet, outflow at the outlet, and the top side designated with specified pressure. Meanwhile, the right and left sides, along with the bottom, are defined as wall boundaries (Günal et al 2019).…”

“…This variation is likely due to water spilling over the blockage barrier, particularly at higher levels of obstruction. As a result, in such instances, the velocity of the water was reduced in comparison to other scenarios, affecting the scouring dynamics (Günal et al 2019;Galán and González 2020;Othman et al 2021).…”

“…The application of numerical approaches via Flow-3D has proven effective, as evidenced by research that aligns numerical simulations closely with results from laboratory experiments. Günal et al (2019) delved into how the ratio of partial blockage affects scour processes downstream of box culverts under unsteady flow conditions, discovering a significant alignment between the results from laboratory experiments and numerical simulations via Flow-3D. On a related note, Kaywan et al ( 2021) assessed the efficacy of numerical models in forecasting scour depths downstream of box culverts under variable flow conditions, finding a reliable match between the predictions made by numerical models and actual experimental outcomes.…”

Impact of Flow in Pipe and Box Coverages on Open Channel’s Performance

“…From dimension analysis and multiple regression analysis, the hypothetical relationships can be as follow. (2) Where: (μ) is the dynamic water viscosity (Kg/m.s), (g) is the gravitational acceleration (m/s 2 ), (  ) is the water density (Kg/m 3 ), (Yu) is the upstream water depth in presence of coverage (m), (Yd) is the downstream water depth in presence of coverage (m), (Ys) is the water depth in the case where there is no coverage (m), (Q) is the water flow rate (L/s), (B) is blocking ratio, (Ar) is the relative wetted area of coverage, and equal (Ap) / (Awe) (where (Awe) is a wetted area of canal upstream coverage (m 2 ), and (Ap) is the area passing water through coverage of box section (m 2 )), (Vu) is water velocity upstream coverage (m/s), (Fru) is the Froude number of the flow upstream the coverage, (Frd) is the Froude number of the flow downstream the coverage, the heading up (hu) is the difference between the water depth upstream coverage and case of no coverage (m), and the head losses (hloss) is the difference between the upstream and downstream water depth for the same case. Tables (2 and 3) display the correlation matrix for the hypothetical relationships, which depicts the strength of the relationship between the independent and the dependent parameters for Pipecoverage and Box-coverage cross-sections.…”

“…The study revealed that the scour depth at high and low tailwater depths is 25% and 70% of the maximum scour depth, respectively. [2] investigated the scour parameters downstream box coverage using flow-3D software. The results were compared to those obtained from a laboratory in Sorouien, and the comparison indicated that the maximum scours depth was higher in all cases whenever the partially blocked condition was present.…”