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Hydrauliciens européens et la SHF
(2002)La Houille BlancheThe Société Hydrotechnique de France SHF (French Hydrotechnical Society) commemorates this year its 100th anniversary. Founded by a group of industrials and scientist its purpose was to mainly advance hydrotechnics to profit of synergies in developing French hydraulics. After an introduction to a current book project European Hydraulicians 1800-2000 to be published in 2003, the author presents a list of French hydraulicians. He then ...Journal Article -
Supercritical flow across sewer manholes
(2002)Journal of Hydraulic EngineeringThe hydraulics of supercritical flow across manholes in sewers is explored using systematic experimentation. Due to the expansion at the manhole entrance an in-manhole wave is generated. Further, at the downstream manhole end, flows with a sufficiently large filling ratio impinge on the wall and lead to a so-called swell. In addition, due to shock wave generation in the downstream sewer, a sewer wave is generated. The heights and locations ...Journal Article -
Undular hydraulic jumps in circular conduits
(2002)Journal of Hydraulic EngineeringUndular hydraulic jumps in circular conduits are considered with an experimental approach. Based on previous findings in rectangular channels, this research indicates differences in terms of shape effects. All present results depend on the filling ratio of the upstream conduit flow in addition to the upstream Froude number. The results include information on the wave crests and troughs, wave lengths, and generalized axial surface profiles. ...Journal Article -
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History of roll waves
(2002)L'AcquaRoll waves may have a significant impact on a hydraulic design of free surface flows in steeper channels, because standard uniform flow becomes unstable to generate a periodic wave train, of which the wave maxima are considerably higher than the uniform flow depth. Roll waves were physically described one hundred years ago, but the present review would also like to highlight the various criteria formulated in the first sixty years of its ...Journal Article -
Shields' entrainment criterion in bridge hydraulics
(2002)Journal of Hydraulic EngineeringTwo related problems of sediment hydraulics are addressed: (1) Inception of sediment transport for nearly uniform flow of both uniform and nonuniform sediment beds for two different sediment densities and grain sizes ranging from sand to gravel, and (2) generalized inception conditions if elements are inserted in a plane sediment bed. The Shields’ criterion is formulated with basic quantities involving gravity, viscosity, and densities ...Journal Article -
Drop in combined sewer manhole for supercritical flow
(2002)Journal of Irrigation and Drainage EngineeringManholes often contain small drops for various reasons, the most important being submergence. While this may be appropriate for subcritical flow, its effect was considered doubtful for supercritical flow. This note aims at investigating the effect of a manhole drop on the hydraulics of sewer flow. Based on systematic experimental observations, the flow pattern associated with a manhole drop was established. A distinction was also made ...Journal Article -
Supercritical flow in manholes with a bend extension
(2002)Experiments in FluidsBend manholes of sewers with 45° deflection angles are considered. Previous results are reconsidered by introducing the so-called bend extension. It is demonstrated that the discharge capacity of the 45°- and the 90°-bend manholes is identical if the bend extension, a U-shaped straight downstream portion, is added to the 45° manhole. In addition, the effect of the bend cover is analyzed as a general means to suppress shock waves. Both ...Journal Article -
Temporal evolution of clear-water pier and abutment scour
(2002)Journal of Hydraulic EngineeringScour related to bridge hydraulics received much attention in the past decade, including its relation to flood hydrology and hydraulic processes in addition to steady flow. This paper presents new research on bridge pier and abutment scour based on a large data set collected at ETH Zurich, Switzerland. In total six different sediments were tested, of which three were uniform. Also a large variety of scour elements were considered, from 1 ...Journal Article -