Modélisation des écoulements d’eaux parasites et leurs impacts dans le collecteur d’assainissement.

Abstract

The systems of evacuation in cleansing, badly maintained or presenting anomalies, generally transport parasitic quantities of water having various origins whose determination proves to be difficult. According to the literature, the presence or the leakage of parasitic water on the level of the collectors of cleansing which are badly managed, pollutes the tablecloths and disturbs the operation of the stations of purification. The intrusion or the extrusion of these waters with variable flow, in the collector, also presents an impact mechanist on the determination of the dominating parameters (speed, height of water) during a transitory mode thus caused and, make often difficult their determination. On the assumption of an intrusion supposed uniformly distributed along the collector, our work initially consists in modelling this flow, in an approached way, and thereafter with a determination of the couple height – speed while being based on the equations of Saint Venant. This study is useful primarily not only for the dimensioning of the collectors of cleansing but also for the wedging of the engineering constructions which are necessary to management such as the rain spillways , the by-pass spillways, etc.....