![Riprap](https://upload.wikimedia.org/wikipedia/commons/9/97/Riprap.jpg)
Hydraulic engineering as a sub-discipline of
civil engineering
Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including public works such as roads, bridges, canals, dams, airports, sewage ...
is concerned with the flow and conveyance of
fluid
In physics, a fluid is a liquid, gas, or other material that continuously deforms (''flows'') under an applied shear stress, or external force. They have zero shear modulus, or, in simpler terms, are substances which cannot resist any shear ...
s, principally
water
Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ...
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 the design of
bridge
A bridge is a structure built to span a physical obstacle (such as a body of water, valley, road, or rail) without blocking the way underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually somethi ...
s,
dam
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, human consumption, industrial use, a ...
s,
channel
Channel, channels, channeling, etc., may refer to:
Geography
* Channel (geography), in physical geography, a landform consisting of the outline (banks) of the path of a narrow body of water.
Australia
* Channel Country, region of outback Austral ...
s,
canal
Canals or artificial waterways are waterways or engineered channels built for drainage management (e.g. flood control and irrigation) or for conveyancing water transport vehicles (e.g. water taxi). They carry free, calm surface flow un ...
s, and
levee
A levee (), dike (American English), dyke (English in the Commonwealth of Nations, Commonwealth English), embankment, floodbank, or stop bank is a structure that is usually soil, earthen and that often runs parallel (geometry), parallel to ...
s, and to both sanitary and
environmental engineering
Environmental engineering is a professional engineering discipline that encompasses broad scientific topics like chemistry, biology, ecology, geology, hydraulics, hydrology, microbiology, and mathematics to create solutions that will protect and a ...
.
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.
[Prasuhn, Alan L. ''Fundamentals of Hydraulic Engineering''. Holt, Rinehart, and Winston: New York, 1987.] Before beginning a hydraulic engineering project, one must figure out how much water 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 plant
A thermal power station is a type of power station in which heat energy is converted to electrical energy. In a steam-generating cycle heat is used to boil water in a large pressure vessel to produce high-pressure steam, which drives a stea ...
s."
Fundamental principles
A few examples of the fundamental principles of hydraulic engineering include
fluid mechanics
Fluid mechanics is the branch of physics concerned with the mechanics of fluids ( liquids, gases, and plasmas) and the forces on them.
It has applications in a wide range of disciplines, including mechanical, aerospace, civil, chemical and bio ...
,
fluid
In physics, a fluid is a liquid, gas, or other material that continuously deforms (''flows'') under an applied shear stress, or external force. They have zero shear modulus, or, in simpler terms, are substances which cannot resist any shear ...
flow, behavior of real fluids,
hydrology
Hydrology () is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and environmental watershed sustainability. A practitioner of hydrology is calle ...
, pipelines, open channel hydraulics, mechanics of
sediment
Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand an ...
transport, physical modeling, hydraulic machines, and drainage hydraulics.
Fluid mechanics
''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 the fluid's surroundings. This pressure, measured in N/m
2, 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,
:''ρ'' = density of water
:''g'' = specific gravity
:''y'' = depth of the body of liquid
Rearranging this equation gives you the
pressure head
In fluid mechanics, pressure head is the height of a liquid column that corresponds to a particular pressure exerted by the liquid column on the base of its container. It may also be called static pressure head or simply static head (but not ''sta ...
. Four basic devices for
pressure measurement
Pressure measurement is the measurement of an applied force by a fluid (liquid or gas) on a surface. Pressure is typically measured in units of force per unit of surface area. Many techniques have been developed for the measurement of pressur ...
are a
piezometer
A piezometer is either a device used to measure liquid pressure in a system by measuring the height to which a column of the liquid rises against gravity, or a device which measures the pressure (more precisely, the piezometric head) of groundwa ...
,
manometer
Pressure measurement is the measurement of an applied force by a fluid (liquid or gas) on a surface. Pressure is typically measured in units of force per unit of surface area. Many techniques have been developed for the measurement of pressur ...
, differential manometer,
Bourdon gauge
Pressure measurement is the measurement of an applied force by a fluid (liquid or gas) on a surface. Pressure is typically measured in units of force per unit of surface area. Many techniques have been developed for the measurement of pressur ...
, as well as an inclined manometer.
As Prasuhn states:
: On undisturbed submerged bodies, pressure acts along all surfaces of a body in a liquid, causing equal perpendicular forces in the body to act against the pressure of the liquid. This reaction is known as equilibrium. More advanced applications of pressure are that on plane surfaces, curved surfaces, dams, and quadrant gates, just to name a few.
Behavior of real fluids
Real and Ideal fluids
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.
Viscous flow
A viscous fluid will deform continuously under a shear force by the pascles law, whereas an ideal fluid does not deform.
Laminar flow and turbulence
The various effects of disturbance on a viscous flow are a stable, transition and unstable.
Bernoulli's equation
For an ideal fluid,
Bernoulli's equation
In fluid dynamics, Bernoulli's principle states that an increase in the speed of a fluid occurs simultaneously with a decrease in static pressure or a decrease in the fluid's potential energy. The principle is named after the Swiss mathematici ...
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
Sheep shearing is the process by which the woollen fleece of a sheep is cut off. The person who removes the sheep's wool is called a '' shearer''. Typically each adult sheep is shorn once each year (a sheep may be said to have been "shorn" or ...
action between 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 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.
[E. John Finnemore, Joseph Franzini "Fluid Mechanics with Engineering Applications", McGraw-Hill,2002] The flow inside the layer can be either vicious or turbulent, depending on Reynolds number.
Applications
Common topics of design for hydraulic engineers include hydraulic structures such as
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, human consumption, industrial use, ...
,
levees
A levee (), dike (American English), dyke (Commonwealth English), embankment, floodbank, or stop bank is a structure that is usually earthen and that often runs parallel to the course of a river in its floodplain or along low-lying coastlin ...
, water distribution networks including both domestic and fire water supply, distribution and automatic sprinkler systems, water collection networks, sewage collection networks,
storm water
Stormwater, also spelled storm water, is water that originates from precipitation (storm), including heavy rain and meltwater from hail and snow. Stormwater can soak into the soil ( infiltrate) and become groundwater, be stored on depressed land ...
management,
sediment transport
Sediment transport is the movement of solid particles (sediment), typically due to a combination of gravity acting on the sediment, and/or the movement of the fluid in which the sediment is entrained. Sediment transport occurs in natural system ...
, and various other topics related to
transportation engineering
Transportation engineering or transport engineering is the application of technology and scientific principles to the planning, functional design, operation and management of facilities for any mode of transportation in order to provide for th ...
and
geotechnical engineering
Geotechnical engineering is the branch of civil engineering concerned with the engineering behavior of earth materials. It uses the principles of soil mechanics and rock mechanics for the solution of its respective engineering problems. It als ...
. Equations developed from the principles of
fluid dynamics
In physics and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids— liquids and gases. It has several subdisciplines, including ''aerodynamics'' (the study of air and other gases in motion) an ...
and
fluid mechanics
Fluid mechanics is the branch of physics concerned with the mechanics of fluids ( liquids, gases, and plasmas) and the forces on them.
It has applications in a wide range of disciplines, including mechanical, aerospace, civil, chemical and bio ...
are widely utilized by other engineering disciplines such as mechanical,
aeronautical
Aeronautics is the science or art involved with the study, design, and manufacturing of air flight–capable machines, and the techniques of operating aircraft and rockets within the atmosphere. The British Royal Aeronautical Society identifies ...
and even traffic engineers.
Related branches include
hydrology
Hydrology () is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and environmental watershed sustainability. A practitioner of hydrology is calle ...
and
rheology
Rheology (; ) is the study of the flow of matter, primarily in a fluid ( liquid or gas) state, but also as "soft solids" or solids under conditions in which they respond with plastic flow rather than deforming elastically in response to an appl ...
while related applications include hydraulic modeling, flood mapping, catchment flood management plans, shoreline management plans, estuarine strategies, coastal protection, and flood alleviation.
History
Antiquity
Earliest uses of hydraulic engineering were to
irrigate crops and dates back to
the Middle East
The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabia (including the Arabian Peninsula and Bahrain), Asia Minor (Asian part of Turkey except Hatay Province), East Thrace (Europea ...
and
Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
. 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
A water clock or clepsydra (; ; ) is a timepiece by which time is measured by the regulated flow of liquid into (inflow type) or out from (outflow type) a vessel, and where the amount is then measured.
Water clocks are one of the oldest time-m ...
was used in the early 2nd millennium BC. Other early examples of using gravity to move water include the
Qanat
A qanat or kārīz is a system for transporting water from an aquifer or water well to the surface, through an underground aqueduct; the system originated approximately 3,000 BC in what is now Iran. The function is essentially the same across ...
system in ancient Persia and the very similar
Turpan water system
The Turpan water system or Turfan karez system ug, كارىز, kariz, 6=кариз) in Turpan, located in the Turpan Depression, Xinjiang, China, is a vertical tunnel system adapted by the Uyghur people. The word ''karez'' means "well" in the l ...
in ancient China as well as irrigation canals in Peru.
In
ancient China
The earliest known written records of the history of China date from as early as 1250 BC, from the Shang dynasty (c. 1600–1046 BC), during the reign of king Wu Ding. Ancient historical texts such as the '' Book of Documents'' (early chapte ...
, hydraulic engineering 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
Ximen Bao was a Chinese hydraulic engineer, philosopher, and politician. He was a government minister and court advisor to Marquis Wen of Wei (reigned 445–396 BC) during the Warring States period of ancient China. He was known as an early ratio ...
was credited of starting the practice of large scale canal irrigation during the
Warring States period
The Warring States period () was an era in History of China#Ancient China, ancient Chinese history characterized by warfare, as well as bureaucratic and military reforms and consolidation. It followed the Spring and Autumn period and concluded ...
(481 BC-221 BC), even today hydraulic engineers remain a respectable position in China. Before becoming
General Secretary of the Communist Party of China
The general secretary of the Chinese Communist Party () is the head of the Chinese Communist Party (CCP), the sole ruling party of the People's Republic of China (PRC). Since 1989, the CCP general secretary has been the paramount leader ...
in 2002,
Hu Jintao
Hu Jintao (born 21 December 1942) is a Chinese politician who served as the 16–17th general secretary of the Chinese Communist Party (CCP) from 2002 to 2012, the 6th president of the People's Republic of China (PRC) from 2003 to 2013, an ...
was a hydraulic engineer and holds an engineering degree from
Tsinghua University
Tsinghua University (; abbreviation, abbr. THU) is a National university, national Public university, public research university in Beijing, China. The university is funded by the Ministry of Education of the People's Republic of China, Minis ...
![Rice Terraces Banaue](https://upload.wikimedia.org/wikipedia/commons/1/17/Rice_Terraces_Banaue.jpg)
In the
Archaic epoch of the Philippines, hydraulic engineering also developed specially in the Island of
Luzon
Luzon (; ) is the largest and most populous island in the Philippines. Located in the northern portion of the Philippines archipelago, it is the economic and political center of the nation, being home to the country's capital city, Manila, as ...
, the
Ifugaos
The Ifugao people are the ethnic groups in the Philippines, ethnic group inhabiting Ifugao Province. They reside in the municipalities of Lagawe (capital of Ifugao), Aguinaldo, Ifugao, Aguinaldo, Alfonso Lista, Asipulo, Banaue, Hingyon, Hungduan ...
of the mountainous region of the
Cordillera
A cordillera is an extensive chain and/or network system of mountain ranges, such as those in the west coast of the Americas. The term is borrowed from Spanish, where the word comes from , a diminutive of ('rope').
The term is most commonly us ...
s built irrigations, dams and hydraulic works and the famous
Banaue Rice Terraces
The Banaue Rice Terraces ( fil, Hagdan-hagdang Palayan ng Banawe) are terraces that were carved into the mountains of Banaue, Ifugao, in the Philippines, by the ancestors of the Igorot people. The terraces are occasionally called the "Eighth ...
as a way for assisting in growing crops around 1000 BC. These Rice Terraces are 2,000-year-old
terrace
Terrace may refer to:
Landforms and construction
* Fluvial terrace, a natural, flat surface that borders and lies above the floodplain of a stream or river
* Terrace, a street suffix
* Terrace, the portion of a lot between the public sidewalk a ...
s that were carved into the mountains of
Ifugao
Ifugao, officially the Province of Ifugao ( ilo, Probinsia ti Ifugao; tl, Lalawigan ng Ifugao), is a landlocked province of the Philippines in the Cordillera Administrative Region in Luzon. Its capital is Lagawe and it borders Benguet to the wes ...
in the
Philippines
The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no),
* bik, Republika kan Filipinas
* ceb, Republika sa Pilipinas
* cbk, República de Filipinas
* hil, Republ ...
by ancestors of the
indigenous people
Indigenous peoples are culturally distinct ethnic groups whose members are directly descended from the earliest known inhabitants of a particular geographic region and, to some extent, maintain the language and culture of those original people ...
. The Rice Terraces are commonly referred to as the "
Eighth Wonder of the World
Eighth Wonder of the World is an unofficial title sometimes given to new buildings, structures, projects, designs or even people that are deemed to be comparable to the seven Wonders of the World.
Candidates for 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
Irrigation (also referred to as watering) is the practice of applying controlled amounts of water to land to help grow Crop, crops, Landscape plant, landscape plants, and Lawn, lawns. Irrigation has been a key aspect of agriculture for over 5,00 ...
system from the rainforests above the terraces. It is said that if the steps were put end to end, it would encircle half the globe.
Eupalinos
Eupalinos ( grc, Εὐπαλῖνος) or Eupalinus of Megara was an ancient Greek engineer who built the Tunnel of Eupalinos on Samos Island in the 6th century BC.
The tunnel, presumably completed between 550 and 530 BC, is the second known tun ...
of
Megara
Megara (; el, Μέγαρα, ) is a historic town and a municipality in West Attica, Greece. It lies in the northern section of the Isthmus of Corinth opposite the island of Salamis Island, Salamis, which belonged to Megara in archaic times, befo ...
, was an
ancient Greek
Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...
engineer
Engineers, as practitioners of engineering, are professionals who invent, design, analyze, build and test machines, complex systems, structures, gadgets and materials to fulfill functional objectives and requirements while considering the l ...
who built the
Tunnel of Eupalinos
The Tunnel of Eupalinos or Eupalinian aqueduct ( el, Ευπαλίνιον όρυγμα, translit=Efpalinion orygma) is a tunnel of length running through Mount Kastro in Samos, Greece, built in the 6th century BC to serve as an aqueduct. The tunn ...
on
Samos
Samos (, also ; el, Σάμος ) is a Greek island in the eastern Aegean Sea, south of Chios, north of Patmos and the Dodecanese, and off the coast of western Turkey, from which it is separated by the -wide Mycale Strait. It is also a separate ...
in the 6th century BC, an important feat of both civil and hydraulic engineering. The civil engineering aspect of this tunnel was the fact that it was dug from both ends which required the diggers to maintain an accurate path so that 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
The Roman Empire ( la, Imperium Romanum ; grc-gre, Βασιλεία τῶν Ῥωμαίων, Basileía tôn Rhōmaíōn) was the post-Republican period of ancient Rome. As a polity, it included large territorial holdings around the Mediterr ...
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
Hydraulic mining is a form of mining that uses high-pressure jets of water to dislodge rock material or move sediment.Paul W. Thrush, ''A Dictionary of Mining, Mineral, and Related Terms'', US Bureau of Mines, 1968, p.560. In the placer mining of ...
methods to prospect and extract alluvial
gold
Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile met ...
deposits in a technique known as
hushing
Hushing is an ancient and historic mining method using a flood or torrent of water to reveal mineral veins. The method was applied in several ways, both in prospecting for ores, and for their exploitation. Mineral veins are often hidden below ...
, and applied the methods to other ores such as those of
tin
Tin is a chemical element with the symbol Sn (from la, stannum) and atomic number 50. Tin is a silvery-coloured metal.
Tin is soft enough to be cut with little force and a bar of tin can be bent by hand with little effort. When bent, t ...
and
lead
Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cu ...
.
In the 15th century, the
Somali Ajuran Empire
The Ajuran Sultanate ( so, Saldanadda Ajuuraan, ar, سلطنة الأجورانية), also natively referred-to as Ajuuraan, and often simply Ajuran, was a Somali Empire in the Middle Ages in the Horn of Africa that dominated the trade in the ...
was the only
hydraulic empire
A hydraulic empire, also known as a hydraulic despotism, hydraulic society, hydraulic civilization, or water monopoly empire, is a social or government structure which maintains power and control through exclusive control over access to water. I ...
in Africa. As a hydraulic empire, the Ajuran State monopolized the
water resources
Water resources are natural resources of water that are potentially useful for humans, for example as a source of drinking water supply or irrigation water. 97% of the water on the Earth is salt water and only three percent is fresh water; slight ...
of the
Jubba
Thawb ( ar, ثَوْب "garment"), also spelled thobe or tobe and known by various other names in different regions, is an ankle-length robe, usually with long sleeves. It is commonly worn in the Arabian Peninsula, the Middle East, North Afr ...
and
Shebelle River
The Shebelle River ( so, Webi Shabeelle, ar, نهر شبيلي, am, እደላ) begins in the Ethiopian Highlands, highlands of Ethiopia, and then flows southeast into Somalia towards Mogadishu. Near Mogadishu, it turns sharply southwest, where ...
s. Through hydraulic engineering, it also constructed many of the
limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...
wells
Wells most commonly refers to:
* Wells, Somerset, a cathedral city in Somerset, England
* Well, an excavation or structure created in the ground
* Wells (name)
Wells may also refer to:
Places Canada
*Wells, British Columbia
England
* Wells ...
and
cistern
A cistern (Middle English ', from Latin ', from ', "box", from Greek ', "basket") is a waterproof receptacle for holding liquids, usually water. Cisterns are often built to catch and store rainwater. Cisterns are distinguished from wells by t ...
s of the state that are still operative and in use today. The rulers developed new systems for
agriculture
Agriculture or farming is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people to ...
and
taxation
A tax is a compulsory financial charge or some other type of levy imposed on a taxpayer (an individual or legal person, legal entity) by a governmental organization in order to fund government spending and various public expenditures (regiona ...
, which continued to be used in parts of the
Horn of Africa
The Horn of Africa (HoA), also known as the Somali Peninsula, is a large peninsula and geopolitical region in East Africa.Robert Stock, ''Africa South of the Sahara, Second Edition: A Geographical Interpretation'', (The Guilford Press; 2004), ...
as late as the 19th century.
Further advances in hydraulic engineering occurred in the
Muslim world
The terms Muslim world and Islamic world commonly refer to the Islamic community, which is also known as the Ummah. This consists of all those who adhere to the religious beliefs and laws of Islam or to societies in which Islam is practiced. I ...
between the 8th to 16th centuries, during what is known as the
Islamic Golden Age
The Islamic Golden Age was a period of cultural, economic, and scientific flourishing in the history of Islam, traditionally dated from the 8th century to the 14th century. This period is traditionally understood to have begun during the reign ...
. Of particular importance was the '
water management technological complex
The Arab Agricultural Revolution was the transformation in agriculture from the 8th to the 13th century in the Islamic region of the Old World. The agronomic literature of the time, with major books by Ibn Bassal and Abū l-Khayr al-Ishbīlī, d ...
' which was central to the
Islamic Green Revolution and,
by extension, a precondition for the emergence of modern technology. The various components of this 'toolkit' were developed in different parts of the
Afro-Eurasia
Afro-Eurasia (also Afroeurasia, Eurafrasia or the Old World) is a landmass comprising the continents of Africa, Asia, and Europe. The terms are compound words of the names of its constituent parts. Its mainland is the largest and most populou ...
n 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 the Old World.
Under the rule of a single Islamic
Caliphate
A caliphate or khilāfah ( ar, خِلَافَة, ) is an institution or public office under the leadership of an Islamic steward with the title of caliph (; ar, خَلِيفَة , ), a person considered a political-religious successor to th ...
, different regional hydraulic technologies were assembled into "an identifiable
water management
Water resources are natural resources of water that are potentially useful for humans, for example as a source of drinking water supply or irrigation water. 97% of the water on the Earth is salt water and only three percent is fresh water; slightl ...
technological complex that was to have a global impact." The various components of this complex included
canal
Canals or artificial waterways are waterways or engineered channels built for drainage management (e.g. flood control and irrigation) or for conveyancing water transport vehicles (e.g. water taxi). They carry free, calm surface flow un ...
s,
dam
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, human consumption, industrial use, a ...
s, the ''
qanat
A qanat or kārīz is a system for transporting water from an aquifer or water well to the surface, through an underground aqueduct; the system originated approximately 3,000 BC in what is now Iran. The function is essentially the same across ...
'' system from Persia, regional water-lifting devices such as the ''
noria
A noria ( ar, ناعورة, ''nā‘ūra'', plural ''nawāʿīr'', from syr, ܢܥܘܪܐ, ''nā‘orā'', lit. "growler") is a hydropowered ''scoop wheel'' used to lift water into a small aqueduct (water supply), aqueduct, either for the purpos ...
,
shaduf
A shadoof or shaduf (from the Arabic language, Arabic word , ''šādūf'') is an irrigation tool. It is highly efficient, and has been known since 3000 BCE.
Names
It is also called a lift, well pole, well sweep, or simply a sweep in the US.Kni ...
'' and
screwpump
The Archimedes screw, also known as the Archimedean screw, hydrodynamic screw, water screw or Egyptian screw, is one of the earliest hydraulic machines. Using Archimedes screws as water pumps (Archimedes screw pump (ASP) or screw pump) dates back ...
from
Egypt
Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Mediter ...
, and the
windmill
A windmill is a structure that converts wind power into rotational energy using vanes called windmill sail, sails or blades, specifically to mill (grinding), mill grain (gristmills), but the term is also extended to windpumps, wind turbines, and ...
from Islamic
Afghanistan
Afghanistan, officially the Islamic Emirate of Afghanistan,; prs, امارت اسلامی افغانستان is a landlocked country located at the crossroads of Central Asia and South Asia. Referred to as the Heart of Asia, it is bordere ...
.
[ Other original Islamic developments included the '']saqiya
Saqiya ( ar, ساقِية, the Arabic name of a mechanical water lifting device) was a village in Palestine ( Jaffa district) away from Jaffa, depopulated in 1948.
Location
The village was located east of Jaffa, above sea level, on uneven l ...
'' with a flywheel
A flywheel is a mechanical device which uses the conservation of angular momentum to store rotational energy; a form of kinetic energy proportional to the product of its moment of inertia and the square of its rotational speed. In particular, ass ...
effect from Islamic Spain,[Ahmad Y Hassan]
Flywheel Effect for a ''Saqiya''
. the reciprocating suction
Suction is the colloquial term to describe the air pressure differential between areas.
Removing air from a space results in a pressure differential. Suction pressure is therefore limited by external air pressure. Even a perfect vacuum cannot ...
pump
A pump is a device that moves fluids (liquids or gases), or sometimes slurries, by mechanical action, typically converted from electrical energy into hydraulic energy. Pumps can be classified into three major groups according to the method they u ...
[Donald Routledge Hill, "Mechanical Engineering in the Medieval Near East", ''Scientific American'', May 1991, pp. 64–9. (cf. Donald Routledge Hill]
Mechanical Engineering
)[Donald Routledge Hill (1996), ''A History of Engineering in Classical and Medieval Times'', ]Routledge
Routledge () is a British multinational publisher. It was founded in 1836 by George Routledge, and specialises in providing academic books, journals and online resources in the fields of the humanities, behavioural science, education, law, and ...
, pp. 143 & 150-2 and crankshaft
A crankshaft is a mechanical component used in a piston engine to convert the reciprocating motion into rotational motion. The crankshaft is a rotating shaft containing one or more crankpins, that are driven by the pistons via the connecting ...
-connecting rod
A connecting rod, also called a 'con rod', is the part of a piston engine which connects the piston to the crankshaft. Together with the crank, the connecting rod converts the reciprocating motion of the piston into the rotation of the cranksh ...
mechanism from Iraq
Iraq,; ku, عێراق, translit=Êraq officially the Republic of Iraq, '; ku, کۆماری عێراق, translit=Komarî Êraq is a country in Western Asia. It is bordered by Turkey to Iraq–Turkey border, the north, Iran to Iran–Iraq ...
,Ahmad Y Hassan
Ahmad Yousef Al-Hassan ( ar, links=no, أحمد يوسف الحسن) (June 25, 1925 – April 28, 2012) was a Palestinian/Syrian/Canadian historian of Arabic and Islamic science and technology, educated in Jerusalem, Cairo, and London with a PhD i ...
The Crank-Connecting Rod System in a Continuously Rotating Machine
the gear
A gear is a rotating circular machine part having cut teeth or, in the case of a cogwheel or gearwheel, inserted teeth (called ''cogs''), which mesh with another (compatible) toothed part to transmit (convert) torque and speed. The basic pr ...
ed and hydropower
Hydropower (from el, ὕδωρ, "water"), also known as water power, is the use of falling or fast-running water to Electricity generation, produce electricity or to power machines. This is achieved by energy transformation, converting the Pot ...
ed water supply system
A water supply network or water supply system is a system of engineered hydrologic and hydraulic components that provide water supply. A water supply system typically includes the following:
# A drainage basin (see water purification – source ...
from Syria
Syria ( ar, سُورِيَا or سُورِيَة, translit=Sūriyā), officially the Syrian Arab Republic ( ar, الجمهورية العربية السورية, al-Jumhūrīyah al-ʻArabīyah as-Sūrīyah), is a Western Asian country loc ...
,[Howard R. Turner (1997), ''Science in Medieval Islam: An Illustrated Introduction'', p. 181, ]University of Texas Press
The University of Texas Press (or UT Press) is a university press that is part of the University of Texas at Austin. Established in 1950, the Press publishes scholarly books and journals in several areas, including Latin American studies, Texan ...
, and the water purification
Water purification is the process of removing undesirable chemicals, biological contaminants, suspended solids, and gases from water. The goal is to produce water that is fit for specific purposes. Most water is purified and disinfected for hu ...
methods of Islamic chemists.
Modern times
In many respects, the fundamentals of hydraulic engineering have not changed since ancient times. Liquids are still moved for 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
William Mulholland (September 11, 1855 – July 22, 1935) was an Irish Americans, Irish American self-taught civil engineer who was responsible for building the infrastructure to provide a water supply that allowed Los Angeles to grow into the la ...
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 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
The Tennessee Valley Authority (TVA) is a federally owned electric utility corporation in the United States. TVA's service area covers all of Tennessee, portions of Alabama, Mississippi, and Kentucky, and small areas of Georgia, North Carolina ...
(TVA) brought work and prosperity to the South by building dams to generate cheap electricity and control flooding in 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 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 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.[Fluid Mechanics]
The modern hydraulic engineer uses the same kinds of computer-aided design
Computer-aided design (CAD) is the use of computers (or ) to aid in the creation, modification, analysis, or optimization of a design. This software is used to increase the productivity of the designer, improve the quality of design, improve c ...
(CAD) tools as many of the other engineering disciplines while also making use of technologies like computational fluid dynamics
Computational fluid dynamics (CFD) is a branch of fluid mechanics that uses numerical analysis and data structures to analyze and solve problems that involve fluid flows. Computers are used to perform the calculations required to simulate th ...
to perform the calculations to accurately predict flow characteristics, GPS
The Global Positioning System (GPS), originally Navstar GPS, is a Radionavigation-satellite service, satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of t ...
mapping to assist in locating the best paths for installing a system and laser-based surveying tools to aid in the actual construction of a system.
See also
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
References
Further reading
* Vincent J. Zipparro, Hans Hasen (Eds), ''Davis' Handbook of Applied Hydraulics'', Mcgraw-Hill
McGraw Hill is an American educational publishing company and one of the "big three" educational publishers that publishes educational content, software, and services for pre-K through postgraduate education. The company also publishes referenc ...
, 4th Edition (1992),
at Amazon.com
* Classification of Organics in Secondary Effluents. M. Rebhun, J. Manka. Environmental Science and Technology, 5, pp. 606–610, (1971). 25.
External links
* International Association of Hydraulic Engineering and Research
Founded in 1935, the 'International Association for Hydro-Environment Engineering and Research (IAHR)'' is a worldwide, not-for-profit, global, independent members-based organisation of engineers, professionals and researchers working in fields re ...
Hydraulic Engineering in Prehistoric Mexico
Hydrologic Engineering Center
* Chanson, H. (2007)
Hydraulic Engineering in the 21st Century : Where to ?
Journal of Hydraulic Research, IAHR, Vol. 45, No. 3, pp. 291–301 (ISSN 0022-1686).
{{Authority control
Hydraulics
Civil engineering
Water resources management