Fonctionnement hydraulique des structures réservoirs pour l'assainissement pluvial : étude des dispositifs de diffusion d'eau et modélisation du couple drain-milieu poreux

摘要

In order to reduce urban runoff flowrates and flooding risks, reservoir structures are more and more used. These "alternative technologies" for urban storm water management improve and control the runoff water quality during raining weather. The bibliographic study presents a fine analysis of the main mechanisms governing the hydraulic behaviour of these structures. The injection of rainwater coming from nearby impervious surfaces or catchments through these porous structures requires some diffusion devices to secure the homogeneous filling, so their functioning is not well known. In the first time, the steady rate water flow within a drain has been studied experimentally followed by a numerical modelling. The second part is devoted to the flow simulation through the porous materials, particularly within complex structures composed of cascade porous reservoirs. Finally, a simplified model was proposed to study the transient water flow within the diffusion-drainage device and the surrounding porous medium by a subflow hydrodynamics finite element calculation code.