Predicting Sedimentation in Urban Sewer Conduits

Sedimentation commonly occurs in urban drainage systems, disrupts flow, and is one of the major causes of inundation. The complicated phenomena that alter the cross-section of sewer conduits include transportation, precipitation, and sedimentation, and need to be analyzed for the proper design and efficient maintenance of urban drainage systems. In this study, the discharge capacity of urban drainage systems is simulated and analyzed by considering the pattern of flow of sediments in sewer conduits through a numerical analysis model. The sites of the highest and lowest accumulation of soil were examined as sedimentation occurred, as was discharge due to accumulation in sewer conduits. The purpose of this study is the examination of mathematical models for two-phase fluid flow analysis and the prediction of sedimentation in urban sewer conduits. An expression for the height of the sedimentation was obtained to assess the discharge capacity of urban drainage systems, and a model to predict accumulation in sewer conduits was developed using non-dimensional variables for inlet velocity, inlet particle volume fraction, and particle size. When subjected to linear regression analysis, the model yielded a high correlation coefficient (R2) of 0.899. This satisfied the aims of this study, to obtain a higher discharge capacity and a plan for the design of urban drainage systems.