Multi‐scale analysis for environmental dispersion in wetland flow under the effect of wind

Abstract

The present study emphasizes a multi‐scale analysis of an environmental dispersionin a fully developed shallow wetland flow under the wind effect, based on the momentum and mass transfer equations. From the classical momentum equation, the depth‐dominated velocity profile is derived for the wetland flow. The environmental dispersion is examined using Mei's multi‐scale analysis on moment equations of concentration in wetlands with wind‐induced effect. Further, the maximum velocity, thickness of separation layer with recirculation and its position are obtained. The increase of depth‐averaged velocity was observed for the larger contribution of conveyance capacity in wetland flows for the enhancement of wind direction. Also, the analytical result showed that the higher magnitude of environmental dispersion led to intensive dispersion process for the depth‐dominated wetland flow. Moreover, for the hierarchical composition of contaminant constituents, the duration and length of influenced region are associated with a certain standard water quality level in wetland.