A two‐layer model for studying 2D dissolved pollutant runoff over impermeable surfaces. Issue 5 (17th May 2021)

• Record Type: Journal Article
• Authors: Zhang, Taotao; Xiao, Yang; Liang, Dongfang; Tang, Hongwu; Xu, Junzeng; Yuan, Saiyu; Wang, Nairu; Luan, Bin
• Is Part Of: Hydrological processes. Volume 35:Issue 5(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-05-17
• Subjects: dissolved pollutant -- impermeable surfaces -- pollutant transport -- rainfall runoff -- rainfall simulation; Hydrology -- Periodicals; Hydrology -- Research -- Periodicals; Hydrologic models -- Periodicals; Hydrological forecasting -- Periodicals; 631.432
• DOI: 10.1002/hyp.14152
• Languages: English
• ISSNs: 0885-6087

Abstract

Abstract: Dissolved pollutants in stormwater are a main contributor to water pollution in urban environments. However, many existing transport models are semi‐empirical and only consider one‐dimensional flows, which limit their predictive capacity. Combining the shallow water and the advection–diffusion equations, a two‐dimensional physically based model is developed for dissolved pollutant transport by adopting the concept of a 'control layer'. A series of laboratory experiments has been conducted to validate the proposed model, taking into account the effects of buildings and intermittent rainfalls. The predictions are found to be in good agreement with experimental observations, which supports the assumption that the depth of the control layer is constant. Based on the validated model, a parametric study is conducted, focusing on the characteristics of the pollutant distribution and transport rate over the depth. The hyetograph, including the intensity, duration and intermittency, of rainfall event has a significant influence on the pollutant transport rates. The depth of the control layer, rainfall intensity, surface roughness and area length are dominant factors that affect the dissolved pollutant transport. Finally, several perspectives of the new pollutant transport model are discussed. This study contributes to an in‐depth understanding of the dissolved pollutant transport processes on impermeable surfaces and urban stormwater management. Abstract : A two‐dimensional two‐layer transport model for dissolved pollutant was proposed and validated by a series of experiments considering the effects of buildings and intermittent rainfalls. The assumption of a constant control layer depth is applicable for the areas with buildings and intermittent rainfall events. The depth of the control layer, rainfall intensity, surface roughness and area length are dominant factors that affect the dissolved pollutant transport.