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41-787: The South Branch of the Penobscot River runs 39.0 miles (62.8 km) northeast through Canada Falls Lake to its drowned confluence with the North Branch of the Penobscot in Seboomook Lake in Pittston Academy Grant (T.2 R.4 NBKP). The two rivers combine to form the West Branch Penobscot River , which flows east from the outlet of Seboomook Lake. Canada Falls Lake is impounded by an early 20th-century dam built on

82-486: A piezometer , manometer , differential manometer, Bourdon gauge , as well as an inclined manometer. As Prasuhn states: The main difference between an ideal fluid and a real fluid is that for ideal flow p 1 = p 2 and for real flow p 1 > p 2 . Ideal fluid is incompressible and has no viscosity. Real fluid has viscosity. Ideal fluid is only an imaginary fluid as all fluids that exist have some viscosity. A viscous fluid will deform continuously under

123-619: A confluence is an industrial site, as in Philadelphia or Mannheim . Often a confluence lies in the shared floodplain of the two rivers and nothing is built on it, for example at Manaus , described below. One other way that confluences may be exploited by humans is as sacred places in religions . Rogers suggests that for the ancient peoples of the Iron Age in northwest Europe, watery locations were often sacred, especially sources and confluences. Pre-Christian Slavic peoples chose confluences as

164-433: A gradients, cascades and an adequate junction angle which is sympathetic to the direction of the watercourse’s flow to minimise turbulent flow, maximise evacuation velocity and to ultimately maximise hydraulic efficiency. Since rivers often serve as political boundaries, confluences sometimes demarcate three abutting political entities, such as nations, states, or provinces, forming a tripoint . Various examples are found in

205-726: A new name (such as the confluence of the Monongahela and Allegheny rivers, forming the Ohio River ); or where two separated channels of a river (forming a river island ) rejoin at the downstream end. The point of confluence where the channel flows into a larger body of water may be called the river mouth . Confluences are studied in a variety of sciences. Hydrology studies the characteristic flow patterns of confluences and how they give rise to patterns of erosion, bars, and scour pools. The water flows and their consequences are often studied with mathematical models . Confluences are relevant to

246-724: A respectable position in China. In the Archaic epoch of the Philippines , hydraulic engineering also developed specially in the Island of Luzon , the Ifugaos of the mountainous region of the Cordilleras built irrigations, dams and hydraulic works and the famous Banaue Rice Terraces as a way for assisting in growing crops around 1000 BC. These Rice Terraces are 2,000-year-old terraces that were carved into

287-450: A river in Maine is a stub . You can help Misplaced Pages by expanding it . Confluence In geography , a confluence (also: conflux ) occurs where two or more watercourses join to form a single channel . A confluence can occur in several configurations: at the point where a tributary joins a larger river ( main stem ); or where two streams meet to become the source of a river of

328-399: A shear force by the pascles law, whereas an ideal fluid does not deform. The various effects of disturbance on a viscous flow are a stable, transition and unstable. For an ideal fluid, Bernoulli's equation holds along streamlines. As the flow comes into contact with the plate, the layer of fluid actually "adheres" to a solid surface. There is then a considerable shearing action between

369-441: A stream contaminated with acid mine drainage combines with a stream with near-neutral pH water; these reactions happen very rapidly and influence the subsequent transport of metals downstream of the mixing zone." A natural phenomenon at confluences that is obvious even to casual observers is a difference in color between the two streams; see images in this article for several examples. According to Lynch, "the color of each river

410-625: A technique known as hushing , and applied the methods to other ores such as those of tin and lead . In the 15th century, the Somali Ajuran Empire was the only hydraulic empire in Africa. As a hydraulic empire, the Ajuran State monopolized the water resources of the Jubba and Shebelle Rivers . Through hydraulic engineering, it also constructed many of the limestone wells and cisterns of

451-447: A thin, viscosity-dominated boundary layer near solid surfaces, and an effectively inviscid outer zone away from the boundaries. This concept explained many former paradoxes and enabled subsequent engineers to analyze far more complex flows. However, we still have no complete theory for the nature of turbulence, and so modern fluid mechanics continues to be combination of experimental results and theory. The modern hydraulic engineer uses

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492-401: A vast assortment of subjects which concern confluences. In hydraulic civil engineering , where two or more underground culverted / artificially buried watercourses intersect, great attention should be paid to the hydrodynamic aspects of the system to ensure the longevity and efficiency of the structure. Engineers have to design these systems whilst considering a list of factors that ensure

533-494: Is determined by many things: type and amount of vegetation in the watershed, geological properties, dissolved chemicals, sediments and biologic content – usually algae ." Lynch also notes that color differences can persist for miles downstream before they finally blend completely. Hydrodynamic behaviour of flow in a confluence can be divided into six distinct features which are commonly called confluence flow zones (CFZ). These include The broader field of engineering encompasses

574-512: Is involved. The hydraulic engineer is concerned with the transport of sediment by the river, the interaction of the water with its alluvial boundary, and the occurrence of scour and deposition. "The hydraulic engineer actually develops conceptual designs for the various features which interact with water such as spillways and outlet works for dams, culverts for highways, canals and related structures for irrigation projects, and cooling-water facilities for thermal power plants ." A few examples of

615-625: Is true for many of our world's largest cities. In much the same way, the central valley of California could not have become such an important agricultural region without effective water management and distribution for irrigation. In a somewhat parallel way to what happened in California, the creation of the Tennessee Valley Authority (TVA) brought work and prosperity to the South by building dams to generate cheap electricity and control flooding in

656-735: Is used to describe the meeting of tidal or other non-riverine bodies of water, such as two canals or a canal and a lake. A one-mile (1.6 km) portion of the Industrial Canal in New Orleans accommodates the Gulf Intracoastal Waterway and the Mississippi River-Gulf Outlet Canal ; therefore those three waterways are confluent there. The term confluence can also apply to the process of merging or flowing together of other substance. For example, it may refer to

697-449: The windmill from Islamic Afghanistan . Other original Islamic developments included the saqiya with a flywheel effect from Islamic Spain, the reciprocating suction pump and crankshaft - connecting rod mechanism from Iraq , and the geared and hydropowered water supply system from Syria . In many respects, the fundamentals of hydraulic engineering have not changed since ancient times. Liquids are still moved for

738-572: The ' water management technological complex ' which was central to the Islamic Green Revolution . The various components of this 'toolkit' were developed in different parts of the Afro-Eurasian landmass, both within and beyond the Islamic world. However, it was in the medieval Islamic lands where the technological complex was assembled and standardized, and subsequently diffused to the rest of

779-470: The 17th and 18th centuries found the inviscid flow solutions unsuitable, and by experimentation they developed empirical equations, thus establishing the science of hydraulics. Late in the 19th century, the importance of dimensionless numbers and their relationship to turbulence was recognized, and dimensional analysis was born. In 1904 Ludwig Prandtl published a key paper, proposing that the flow fields of low-viscosity fluids be divided into two zones, namely

820-623: The Middle East and Africa . Controlling the movement and supply of water for growing food has been used for many thousands of years. One of the earliest hydraulic machines, the water clock was used in the early 2nd millennium BC. Other early examples of using gravity to move water include the Qanat system in ancient Persia and the very similar Turpan water system in ancient China as well as irrigation canals in Peru. In ancient China , hydraulic engineering

861-467: The Old World. Under the rule of a single Islamic caliphate , different regional hydraulic technologies were assembled into "an identifiable water management technological complex that was to have a global impact." The various components of this complex included canals , dams , the qanat system from Persia, regional water-lifting devices such as the noria , shaduf and screwpump from Egypt , and

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902-613: The South Branch Penobscot River 5 miles (8.0 km) upstream of its confluence with the North Branch Penobscot River. The lake created behind the dam in Pittston Academy Grant floods the South Branch Penobscot River westerly into Alder Brook Township and tributary Alder Brook southerly into Soldiertown Township. Most of the lake is less than 15 feet (4.6 m) deep. When full, Canada Falls Lake has

943-864: The boundary layer is free of shear and viscous-related forces so it is assumed to act as an ideal fluid. The intermolecular cohesive forces in a fluid are not great enough to hold fluid together. Hence a fluid will flow under the action of the slightest stress and flow will continue as long as the stress is present. The flow inside the layer can be either vicious or turbulent, depending on Reynolds number. Common topics of design for hydraulic engineers include hydraulic structures such as dams , levees , water distribution networks including both domestic and fire water supply, distribution and automatic sprinkler systems, water collection networks, sewage collection networks, storm water management, sediment transport , and various other topics related to transportation engineering and geotechnical engineering . Equations developed from

984-401: The design of bridges , dams , channels , canals , and levees , and to both sanitary and environmental engineering . Hydraulic engineering is the application of the principles of fluid mechanics to problems dealing with the collection, storage, control, transport, regulation, measurement, and use of water. Before beginning a hydraulic engineering project, one must figure out how much water

1025-440: The discharge point is structurally stable as the entrance of the lateral culvert into the main structure may compromise the stability of the structure due to the lack of support at the discharge, this often constitutes additional supports in the form of structural bracing. The velocities and hydraulic efficiencies should be meticulously calculated and can be altered by integrating different combinations of geometries, components such

1066-499: The distribution of living organisms (i.e., ecology ) as well; "the general pattern [downstream of confluences] of increasing stream flow and decreasing slopes drives a corresponding shift in habitat characteristics." Another science relevant to the study of confluences is chemistry , because sometimes the mixing of the waters of two streams triggers a chemical reaction, particularly in a polluted stream. The United States Geological Survey gives an example: "chemical changes occur when

1107-535: The fluid's surroundings. This pressure, measured in N/m , is not constant throughout the body of fluid. Pressure, p, in a given body of fluid, increases with an increase in depth. Where the upward force on a body acts on the base and can be found by the equation: where, Rearranging this equation gives you the pressure head p ρ g = y {\displaystyle {\frac {p}{\rho g}}=y} . Four basic devices for pressure measurement are

1148-437: The fundamental principles of hydraulic engineering include fluid mechanics , fluid flow, behavior of real fluids, hydrology , pipelines, open channel hydraulics, mechanics of sediment transport, physical modeling, hydraulic machines, and drainage hydraulics. Fundamentals of Hydraulic Engineering defines hydrostatics as the study of fluids at rest. In a fluid at rest, there exists a force, known as pressure, that acts upon

1189-424: The largest surface area of any lake on the South Branch Penobscot River; but the lake is usually drained by late summer, and remains low until filled by snowmelt the following spring. Brook trout spawning upstream of the lake and in tributaries Hale Brook, Mullen Brook, and Cunningham Brook spend the warmer months in cool spring seepage areas in the main river channel through the lake. This article related to

1230-418: The layer of fluid on the plate surface and the second layer of fluid. The second layer is therefore forced to decelerate (though it is not quite brought to rest), creating a shearing action with the third layer of fluid, and so on. As the fluid passes further along with the plate, the zone in which shearing action occurs tends to spread further outwards. This zone is known as the "boundary layer". The flow outside

1271-553: The list below. A number of major cities, such as Chongqing , St. Louis , and Khartoum , arose at confluences; further examples appear in the list. Within a city, a confluence often forms a visually prominent point, so that confluences are sometimes chosen as the site of prominent public buildings or monuments, as in Koblenz , Lyon , and Winnipeg . Cities also often build parks at confluences, sometimes as projects of municipal improvement, as at Portland and Pittsburgh . In other cases,

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1312-403: The merger of the flow of two glaciers . Hydraulic engineering Hydraulic engineering as a sub-discipline of civil engineering is concerned with the flow and conveyance of fluids , principally water and sewage. One feature of these systems is the extensive use of gravity as the motive force to cause the movement of the fluids. This area of civil engineering is intimately related to

1353-534: The most part by gravity through systems of canals and aqueducts, though the supply reservoirs may now be filled using pumps. The need for water has steadily increased from ancient times and the role of the hydraulic engineer is a critical one in supplying it. For example, without the efforts of people like William Mulholland the Los Angeles area would not have been able to grow as it has because it simply does not have enough local water to support its population. The same

1394-521: The mountains of Ifugao in the Philippines by ancestors of the indigenous people . The Rice Terraces are commonly referred to as the " Eighth Wonder of the World ". It is commonly thought that the terraces were built with minimal equipment, largely by hand. The terraces are located approximately 1500 metres (5000 ft) above sea level. They are fed by an ancient irrigation system from the rainforests above

1435-503: The principles of fluid dynamics and fluid mechanics are widely utilized by other engineering disciplines such as mechanical, aeronautical and even traffic engineers. Related branches include hydrology and rheology while related applications include hydraulic modeling, flood mapping, catchment flood management plans, shoreline management plans, estuarine strategies, coastal protection, and flood alleviation. Earliest uses of hydraulic engineering were to irrigate crops and dates back to

1476-594: The region, making rivers navigable and generally modernizing life in the region. Leonardo da Vinci (1452–1519) performed experiments, investigated and speculated on waves and jets, eddies and streamlining. Isaac Newton (1642–1727) by formulating the laws of motion and his law of viscosity, in addition to developing the calculus, paved the way for many great developments in fluid mechanics. Using Newton's laws of motion, numerous 18th-century mathematicians solved many frictionless (zero-viscosity) flow problems. However, most flows are dominated by viscous effects, so engineers of

1517-448: The sites for fortified triangular temples, where they practiced human sacrifice and other sacred rites. In Hinduism , the confluence of two sacred rivers often is a pilgrimage site for ritual bathing. In Pittsburgh, a number of adherents to Mayanism consider their city's confluence to be sacred. Mississippi basin Atlantic watersheds Pacific watersheds Occasionally, "confluence"

1558-553: The state that are still operative and in use today. The rulers developed new systems for agriculture and taxation , which continued to be used in parts of the Horn of Africa as late as the 19th century. Further advances in hydraulic engineering occurred in the Muslim world between the 8th and 16th centuries, during what is known as the Islamic Golden Age . Of particular importance was

1599-478: The terraces. It is said that if the steps were put end to end, it would encircle half the globe. Eupalinos of Megara was an ancient Greek engineer who built the Tunnel of Eupalinos on Samos in the 6th century BC, an important feat of both civil and hydraulic engineering. The civil engineering aspect of this tunnel was that it was dug from both ends which required the diggers to maintain an accurate path so that

1640-583: The two tunnels met and that the entire effort maintained a sufficient slope to allow the water to flow. Hydraulic engineering was highly developed in Europe under the aegis of the Roman Empire where it was especially applied to the construction and maintenance of aqueducts to supply water to and remove sewage from their cities. In addition to supplying the needs of their citizens they used hydraulic mining methods to prospect and extract alluvial gold deposits in

1681-526: Was highly developed, and engineers constructed massive canals with levees and dams to channel the flow of water for irrigation, as well as locks to allow ships to pass through. Sunshu Ao is considered the first Chinese hydraulic engineer. Another important Hydraulic Engineer in China, Ximen Bao was credited of starting the practice of large scale canal irrigation during the Warring States period (481 BC–221 BC), even today hydraulic engineers remain

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