Discrete Phase Modelling of Sediment Transport and Scouring of Suspended Particles in Dam Spillway

One of foremost issue arise in the dam management and dam reliability assessment is the sedimentation of suspended particles. Sedimentation affected the energy production and efficiency, storage, discharge capacity, and flood attenuation capabilities. In this paper, the sediment transport and scouring in the dam spillway structure was modelled using finite volume method (FVM) based software, ANSYS. The trajectory of suspended particles in the water flow was formulated based on the discrete phase model (DPM). To access the simulation model, particle image velocimetry (PIV) experiment using scaled-down dam spillway model was conducted. The discrepancy between the findings attained from simulation and PIV experiment is less than 4.89%, inferred the numerical model was acceptable. It was found that the maximum scouring rate and maximum deposition rate are respectively 4.20×10−9 kg/s and 2.00×10−6 kg/s. As such, it was empirically approximated the dam maintenance should be scheduled once every 8.9 years, based on sole consideration on resolving the scouring and deposition of suspended particles. This work demonstrated the viability of DPM based numerical simulation in study the fluid-particle interaction of sediment transport problem, particularly for the application of dam reliability.