Flow-improving elements in circular drop manholes

摘要: ABSTRACTDrop manholes are widely employed in urban drainage systems. They experience operating conditions which insufficient energy dissipation leads to hydraulic problems that enhanced by particular configurations of the manhole bottom. Therefore, specific jet-breaker devices were considered improve flow conditions. Two different types jet-breakers have been tested present work: plane (PJB) and wedge (WJB). Both proved be effective inducing adequate loss, if properly sized, overall drop performance. The selection a element should account for additional features hydraulics, including pool depth, air entrainment phenomena, as well further practical aspects cost-effectiveness, simplicity realization clogging risk. This study provides basis design jet-breakers, particularly PJB, has an optimum performance,...