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Spillways
A spillway is a structure used to provide the controlled release of water downstream from a dam or levee, typically into the riverbed of the dammed river itself. In the United Kingdom, they may be known as overflow channels. Spillways ensure that water does not damage parts of the structure not designed to convey water. Spillways can include floodgates and fuse plugs to regulate water flow and reservoir level. Such features enable a spillway to regulate downstream flow—by releasing water in a controlled manner before the reservoir is full, operators can prevent an unacceptably large release later. Other uses of the term "spillway" include bypasses of dams and outlets of channels used during high water, and outlet channels carved through natural dams such as moraines. Water normally flows over a spillway only during flood periods, when the reservoir has reached its capacity and water continues entering faster than it can be released. In contrast, an intake tower is a struct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic Jump
A hydraulic jump is a phenomenon in the science of hydraulics which is frequently observed in open channel flow such as rivers and spillways. When liquid at high velocity discharges into a zone of lower velocity, a rather abrupt rise occurs in the liquid surface. The rapidly flowing liquid is abruptly slowed and increases in height, converting some of the flow's initial kinetic energy into an increase in potential energy, with some energy irreversibly lost through turbulence to heat. In an open channel flow, this manifests as the fast flow rapidly slowing and piling up on top of itself similar to how a shockwave forms. It was first observed and documented by Leonardo da Vinci in the 1500s. The mathematics were first described by Giorgio Bidone of Turin University when he published a paper in 1820 called ''Experiences sur le remou et sur la propagation des ondes''. The phenomenon is dependent upon the initial fluid speed. If the initial speed of the fluid is below the critical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stepped Spillway
A stepped spillway is a spillway with steps on the spillway chute to assist in the dissipation of the kinetic energy of the descending water. This eliminates or reduces the need for an additional energy dissipator, such as a body of water, at the end of the spillway downstream. Historical developments Stepped spillways, consisting of weirs and channels, have been used for over 3,500 years since the first structures were built in Greece and Crete. During Antiquity, the stepped chute design was used for dam spillways, storm waterways, and in the town water supply channels. Most of these early structures were built around the Mediterranean Sea, and the expertise on stepped spillway design was spread successively by the Romans, Muslims and Spaniards. Although the early stepped spillways were built in cut-stone masonry, unlined rock and timber, a wider range of construction materials was introduced during the mid-19th century, including the first concrete stepped spillway of the Gold ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Dams
A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, tap water, human consumption, Industrial water, industrial use, aquaculture, and navigability. Hydropower is often used in conjunction with dams to generate electricity. A dam can also be used to collect or store water which can be evenly distributed between locations. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees (also known as Dike (construction), dikes) are used to manage or prevent water flow into specific land regions. The earliest known dam is the Jawa Dam (Jordan), Jawa Dam in Jordan, dating to 3,000 BC. The word ''dam'' can be traced back to Middle English, and before that, from Middle Dutch, as seen in the names of many old cities, such as Amsterdam and Rotterdam. History Ancient dams Early dam build ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hubert Chanson
Hubert Chanson (born 1 November 1961) is a professional engineer and academic in hydraulic engineering and environmental fluid mechanics. Since 1990 he has worked at the University of Queensland. Research Hubert Chanson is Professor of Civil Engineering at the University of Queensland, where he has been since 1990, having previously enjoyed an industrial career for six years. His main field of expertise is environmental fluid mechanics and hydraulic engineering, both in terms of theoretical fundamentals, physical and numerical modelling. He leads a group of five to ten researchers, largely targeting flows around hydraulic structures, two-phase (gas-liquid and solid-liquid) free-surface flows, turbulence in steady and unsteady open channel flows, using computation, lab-scale experiments, field work and analysis. He serves on the editorial boards of International Journal of Multiphase Flow, Flow Measurement and Instrumentation, and Environmental Fluid Mechanics, the latter of wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floodgate
Floodgates, also called stop gates, are adjustable gates used to control water flow in flood barriers, reservoir, river, stream, or levee systems. They may be designed to set spillway crest heights in dams, to adjust flow rates in sluices and canals, or they may be designed to stop water flow entirely as part of a levee or storm surge system. Since most of these devices operate by controlling the water surface elevation being stored or routed, they are also known as crest gates. In the case of flood bypass systems, floodgates sometimes are also used to lower the water levels in a main river or canal channels by allowing more water to flow into a flood bypass or detention basin when the main river or canal is approaching a flood stage. Types Valves Valves used in floodgate applications have a variety of design requirements and are usually located at the base of dams. Often, the most important requirement (besides regulating flow) is energy dissipation. Since water is v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fuse Plug
A fuse plug is a collapsible dam installed on spillways in dams to increase the dam's capacity. The principle behind the fuse plug is that the majority of water that overflows a dam's spillway can be safely dammed except in high flood conditions. The fuse plug may be a sand-filled container, a steel structure or a concrete block. Under normal flow conditions the water will spill over the fuse plug and down the spillway. In high flood conditions, where the water velocity may be so high that the dam itself may be put in danger, the fuse plug simply washes away, and the flood waters safely spill over the dam. Fuse plugs are used in many dams throughout the world, including at Warragamba Dam in New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es .... Its fuse plugs are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intake Tower
An intake tower or outlet tower is a vertical tubular structure with one or more openings used for capturing water from reservoirs and conveying it further to a hydroelectric or water-treatment plant. Unlike spillways, intake towers are intended for the reservoir's regular operation, conveying clean, debris-free water for further use. Construction An intake tower is typically made from reinforced concrete, with foundations laid in the river or lake bed. It has at least one water-collecting opening at the top, and may have additional openings along its height, depending on the purpose: towers for hydroelectric plants typically have only one inlet, while those in water-processing plants have multiple draw-off inlets. Near the bottom of the tower, depending on the dam construction and plant location, a horizontal or slanted outlet conduit takes the water from the tower into the plant. The most convenient location for an intake tower is in the proximity of the processing plant. In ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroelectricity
Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, which is more than all other renewable sources combined and also more than nuclear power. Hydropower can provide large amounts of low-carbon electricity on demand, making it a key element for creating secure and clean electricity supply systems. A hydroelectric power station that has a dam and reservoir is a flexible source, since the amount of electricity produced can be increased or decreased in seconds or minutes in response to varying electricity demand. Once a hydroelectric complex is constructed, it produces no direct waste, and almost always emits considerably less greenhouse gas than fossil fuel-powered energy plants. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hungry Horse Dam
Hungry Horse Dam is an arch dam in the western United States, on the South Fork Flathead River in the Rocky Mountains of northwest Montana. It is located in Flathead National Forest in Flathead County, about south of the west entrance to Glacier National Park, southeast of Columbia Falls, and northeast of Kalispell. The Hungry Horse project, dam, and powerplant are operated by the U.S. Bureau of Reclamation. The entrance road leading to the dam is located in Hungry Horse. The purposes of the Hungry Horse Project authorized by law are irrigation, flood control, navigation, streamflow regulation, hydroelectric generation, and other beneficial uses such as recreation. However, no irrigation facilities were built and the project has no irrigation obligations. Hydroelectric power generation and flood control are the primary purposes of the dam. The dam, reservoir, and surrounding area are used for recreation. Dimensions and statistics At in height, the dam was the third lar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geehi Dam
Geehi Dam is a major ungated rockfill dam, rockfill embankment dam, embankment dam across the Geehi River in the Snowy Mountains of New South Wales, Australia. The reservoir impounded by the dam is known as Geehi Reservoir. History The structure was completed by Thiess Pty Ltd, Thiess Brothers in 1966, and is one of the sixteen major dams that comprise the Snowy Mountains Scheme, a vast hydroelectricity and irrigation complex constructed in south-east Australia between 1949 and 1974 that is now run by Snowy Hydro. Location and features The dam is located within what is now the Snowy Valleys Council, Snowy Valleys Local government areas of New South Wales, local government area. It was constructed by Thiess Pty Ltd, Thiess Bros based on engineering plans developed under contract by the Snowy Mountains Hydroelectric Authority. The dam wall, comprising of rockfill with an earth core, is high and long. At 100% capacity the dam wall holds back of water. The surface area of Geehi R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Government Printing Office
The United States Government Publishing Office (USGPO or GPO; formerly the United States Government Printing Office) is an agency of the legislative branch of the United States Federal government. The office produces and distributes information products and services for all three branches of the Federal Government, including U.S. passports for the Department of State as well as the official publications of the Supreme Court, the Congress, the Executive Office of the President, executive departments, and independent agencies. An act of Congress changed the office's name to its current form in 2014. History The Government Printing Office was created by congressional joint resolution () on June 23, 1860. It began operations March 4, 1861, with 350 employees and reached a peak employment of 8,500 in 1972. The agency began transformation to computer technology in the 1980s; along with the gradual replacement of paper with electronic document distribution, this has led to a ste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siphon
A siphon (from grc, σίφων, síphōn, "pipe, tube", also spelled nonetymologically syphon) is any of a wide variety of devices that involve the flow of liquids through tubes. In a narrower sense, the word refers particularly to a tube in an inverted "U" shape, which causes a liquid to flow upward, above the surface of a reservoir, with no pump, but powered by the fall of the liquid as it flows down the tube under the pull of gravity, then discharging at a level lower than the surface of the reservoir from which it came. There are two leading theories about how siphons cause liquid to flow uphill, against gravity, without being pumped, and powered only by gravity. The traditional theory for centuries was that gravity pulling the liquid down on the exit side of the siphon resulted in reduced pressure at the top of the siphon. Then atmospheric pressure was able to push the liquid from the upper reservoir, up into the reduced pressure at the top of the siphon, like in a baromet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
