Application of ANSYS-Fluent Software for Innovative Stepped Dissipation Blocks Arrangement in Ogee Spillway

Abstract

The Ogee Spillway is one of the most crucial flood control structures, and it is developed at the same time as dams. The Ogee Spillway's downstream portions experience scouring due to flow, a problem that persists in reality. This paper aims to investigate the hydraulic performance of stepped block dissipater using a three-dimensional simulation model. The dissipated block was given a new distribution that may be one, two, or three rows in the transverse arrangement at a right angle with the path lines. The numerical simulations for flow and scour were performed using the computational fluid dynamics (CFD) ANSYS-Fluent software. Under Froude numbers ranging from 2.75 to 9.25, the sequence depth and transverse velocity distribution were measured. According to the results, the employed blocks minimized flow rates and sediment scouring throughout the stilling basin in line with suggested distributions, particularly with the Fr 4.5-9.25 range. With values in the 0.95-0.98 range of Correlation Coefficient (R2) and 0.43-0.45 of Root Mean Square Error (RMSE) the coefficient and the comparison of the computational and experimental data looked to be in good agreement. The results proved that the stepped block configuration with (A1, A2, and A3) block distributions, where the A3 distribution appeared with good results of reducing flow velocities within the stilling basin following A1 and A2 distributions, especially with the range of Fr 4.5-8.5. Also, good stability of the hydraulic jump was observed when using A3, while this was difficult to achieve by using both A1 and A2.