An experimental and numerical study investigating sediment transport position in the bed of sewer pipes in Karbala

Abstract

The complex phenomenon of sedimentation in urban areas is well studied using numerical models. Because they may be used to mimic sediment flow, obstructions, and drainage system optimization, the simulations are useful in urban planning and design. By merging ANSYS Fluent with Rocky, researchers were able to track the motion of sediment particles of various sizes and speeds. The sizes of the sediment particles were measured using a sieve after being collected from the streets of Karbala. The particle sizes established by the sieve analysis were used in both the computational and experimental procedures. Varied particle sizes and velocities, including 0.1, 0.2, 0.3, 0.35, 0.4, and 0.49 m/s, as well as varied particle sizes, including 0.4, 0.6, 0.8, 0.1, and 1.2 mm, were investigated. Numerical analysis showed that 1.2 mm-sized particles sedimented between 10 and 148 cm from the input pipe’s X coordinate at a rate of 0.49 m/s. A maximum sedimentation distance of 380 cm was also observed for particles with a diameter of 1 mm. Sediment did not include 0.4 mm-sized objects flowing at the same speed. The findings demonstrated that particle size and velocity significantly impacted the quantity of drag and lift forces acting on the particles. As the particle size increased, the drag force increased, which led to more sedimentation. The particle positions along the X coordinate (pipe bed) showed a declining trend. Overall, this work offers crucial insights for understanding sediment transport in urban drainage systems by illuminating the connection between velocity, particle size, and sedimentation behaviour.

Keywords

• sedimentation
• velocity of water
• sewer pipe