Washington, D.C.: National Park Service, U.S. ^ Guidelines for Identifying, Evaluating and Registering Historic Mining Sites.Hydroelectric Developments and Engineering. Styles of flow measurement flumes include: Cutthroat, HS / H / HL-type, Khafagi, Montana, RBC, Parshall, Palmer-Bowlus, Trapezoidal, and Venturi Flume.įlow measurement flumes can be installed in earthen channels, concrete canals, below ground chambers, or factory integrated into Packaged Metering Manholes. Most flume styles readily allow for the passage of sedimentation and floating debris – reducing the time and effort associated with maintaining a flume installation.Unauthorized altering of the dimensions of constructed flumes is difficult (and therefore unlikely).The velocity of approach is part of the calibration equations for flumes.For the same control width, the head loss for a flume is about one-fourth of that needed to operate a sharp-crested weir.įlumes offer distinct advantages over sharp-crested weirs:
#Water concrete flume portable
Other flumes omit the diverging section (Montana, USGS Portable Parshall, and HS / H / HL flumes). In the case of the Cutthroat flume, the converging section directly joins the diverging section, resulting in a throat section of no length (hence the term "Cutthroat").
Not all sections, however, need to be present. įlow measurement flumes typically consist of a converging section, a throat section, and a diverging section. Acceleration is accomplished through a convergence of the sidewalls, a change in floor elevation, or a combination of the two. When used to measure the flow of water in open channels, a flume is defined as a specially shaped, fixed hydraulic structure that under free-flow conditions forces flow to accelerate in such a manner that the flow rate through the flume can be characterized by a level-to-flow relationship as applied to a single head (level) measurement within the flume. Some varieties of flumes are used in measuring water flow of a larger channel. Log flumes use the flow of water to carry cut logs and timber downhill, sometimes many miles, to either a sawmill or location for further transport.
It is used in America for a very narrow gorge running between precipitous rocks, with a stream at the bottom, but more frequently is applied to an artificial channel of wood or other material for the diversion of a stream of water from a river for purposes of irrigation, for running a sawmill, or for various processes in the hydraulic method of gold-mining. It was formerly used for a stream, and particularly for the tail of a mill race. The term flume comes from the Old French word flum, from the Latin flumen, meaning a river. They were also extensively used in hydraulic mining and working placer deposits for gold, tin and other heavy minerals. Originating as a part of a mill race, they were later used in the transportation of logs in the logging industry, known as a log flume. Many flumes took the form of wooden troughs elevated on trestles, often following the natural contours of the land. Flumes are usually made up of wood, metal or concrete. Flumes route water from a diversion dam or weir to a desired materiel collection location. Flumes are not to be confused with aqueducts, which are built to transport water, rather than transporting materials using flowing water as a flume does. A flume is a human-made channel for water, in the form of an open declined gravity chute whose walls are raised above the surrounding terrain, in contrast to a trench or ditch.
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