Longitudinal Dispersion due to Surcharged Manhole

Abstract

New data describing the longitudinal dispersion of a solute tracer due to a surcharged manhole structure are presented. The increase in both travel time and dispersion caused by this structure is quantified over ranges of discharge and surcharge. Discharge variations exhibit clear trends, whereas surcharge variations are less evident. The results are presented as both Taylor dispersion coefficients and values of parameters used in aggregated dead zone modeling. The limitations of using surcharged averaged parameters with each technique for describing mixing due to a surcharged manhole structure are illustrated. The study shows that the presence of manhole structures within urban drainage schemes has a significant effect on both the travel time and mixing processes of a solute. It is suggested that these processes should be included for the accurate modeling of urban drainage schemes.