Modeling the Performance of Sediment Detention Ponds. Volume 2. The Basin Model Based on Advection-Diffusion and Reactor Mixing Concepts

摘要

An algorithm is presented to model the movement of sediment in detention ponds. The cornerstone of this algorithm is the coupling of reactor theory concepts with advection-diffusion processes. Reactor theory concepts are used for (1) determining residence times of sediment particles, and (2) calculation of mixing in the horizontal plane. Advection-diffusion processes are used to model (1) the settling characteristics of sediment, and (2) the turbulent diffusion of sediment. Also incorporated in the pond model is a bad scour routine based on the statistical properties of turbulent lift forces. Empirical coefficients for the bed scour routine are evaluated by using previously published results. Experimental data were gathered on a pilot scale pond to measure turbulent flow characteristics and to test the accuracy of the proposed algorithm.