Artificially roughened pipe for sewerage systems has been experimentally studied. laboratory tests were aimed at measuring the down-flow scales a different slopes, from 2degrees to 10degrees, and at determining the dependence of the roughness coefficient for the particular pipe. It has been observed that Chezy roughness coefficient is a function of the pipe slope, that is, the average velocity of flow, because of the hyper-turbulent flow caused by the vortex generated by the roughness elements distributed along the pipe. The occurrence of a hyper-turbulent flow over a rough pipe confirms the results obtained by H.M. Morris in 1955; in particular, the dependence of the friction factor on the Reynolds number increases in the case of a normal turbulent flow. From a technical viewpoint the abnormal turbulence along the pipe walls generates other dissipations that cause a slowing down of the flow which also is useful in sewer systems installed on sloping soils. Besides, the abnormal intense turbulence at wall should have a positive self-cleaning effect on the pipe.
Experimental study of artificially roughened sewer / Giustolisi, Orazio. - STAMPA. - (2001), pp. 301-309. (Intervento presentato al convegno 29th Annual Congress of the International-Association-of-Hydraulic-Engineering-and-Research, IAHR tenutosi a Beijing, China nel September 16-21, 2001).
Experimental study of artificially roughened sewer
Giustolisi, Orazio
2001-01-01
Abstract
Artificially roughened pipe for sewerage systems has been experimentally studied. laboratory tests were aimed at measuring the down-flow scales a different slopes, from 2degrees to 10degrees, and at determining the dependence of the roughness coefficient for the particular pipe. It has been observed that Chezy roughness coefficient is a function of the pipe slope, that is, the average velocity of flow, because of the hyper-turbulent flow caused by the vortex generated by the roughness elements distributed along the pipe. The occurrence of a hyper-turbulent flow over a rough pipe confirms the results obtained by H.M. Morris in 1955; in particular, the dependence of the friction factor on the Reynolds number increases in the case of a normal turbulent flow. From a technical viewpoint the abnormal turbulence along the pipe walls generates other dissipations that cause a slowing down of the flow which also is useful in sewer systems installed on sloping soils. Besides, the abnormal intense turbulence at wall should have a positive self-cleaning effect on the pipe.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
