Representation of solute transport and mixing within a surcharged benched manhole using an Aggregated Dead Zone (ADZ) technique

Previous studies of the effects of manhole structures on the longitudinal dispersion of a soluble pollutant have been provided for unbenched manholes, concentrating on determining the dispersion effect by employing a rate of change of second moment of area of the temporal concentration distribution. This paper provides new results from over 350 individual experiments for a manhole structure containing benching with flow rates between 2 and 7.6 l/s. The effects of discharge and surcharge on both the solute travel time and the spreading of the solute slug are quantified. The results are used to estimate the parameters required to simulate the effects of the manhole on solute mixing using an Aggregated Dead Zone (ADZ) technique. Values of the mean parameters ale presented together with an initial assessment of the predictive capability of the technique. Copyright (C) 1996 IAWQ. Published by Elsevier Science Ltd.