The Archimedes screw consists of a screw (a helical surface surrounding a central cylindrical shaft) inside a hollow pipe. The screw is usually turned by windmill, manual labor, cattle, or by modern means, such as a motor. As the shaft turns the bottom end scoops up a volume of water. The (Archimedean) screw Pumps are well-known for their excellent qualities such as the simple & rugged design, the high efficiency, the capacity to pump raw water and their lifetime reliability. The (Archimedean) screw Pumps are well-known for their excellent qualities such as the simple & rugged design, the high efficiency, the capacity to. Archimedes screw pumps consist of a screw (a helical surface surrounding a central cylindrical shaft) inside a hollow pipe. The screw in this case is turned by a geared motor. As the shaft turns, the bottom end scoops up a volume of water or other liquid.
THE ARCHIMEDEAN SCREW-PUMP: A NOTE ON ITS INVENTION AND THE DEVELOPMENT OF THE THEORY Teun Koetsier & Hendrik Blauwendraat. Relation of cylindrical helix and rectangular triangle is not only used to design a screw, but Heron also explains the functioning of the screw as follows (8, p. When designing an Archimedes screw for a specific site, it is necessary to optimize over a range of variables, including the screw inner diameter D i and outer diameter D o, screw pitch P, number of flights N, overall length L and slope (Fig.
The Archimedes screw was operated by hand and could raise water efficiently
An Archimedes screw in Huseby south of Växjö Sweden
In Memphis, Tenn. Each Pump Has Capacity of 19,900 gal./min (Courtesy Lakeside Equipment Corp., Bartlett, Ill.) proved valuable in installations where damage to aquatic life must be minimized. The purpose of this paper is to examine the optimal design of an Archimedes screw. By this is meant that geometry that.
Archimedes screw
Roman screw used to dewater mines in Spain
Modern Archimedes screws which have replaced some of the windmills used to drain the polders at Kinderdijk in the Netherlands
Archimedes screw as a form of art by Tony Cragg at 's-Hertogenbosch in the Netherlands
The water screw, popularly known as the Archimedes' screw and also known as the screw pump, Archimedean screw, or Egyptian screw,[1] is a machine used for transferring water from a low-lying body of water into irrigation ditches. Water is pumped by turning a screw-shaped surface inside a pipe. Archimedes screws are also used for materials such as powders and grains. Although commonly attributed to Archimedes, the device had been used in Ancient Egypt long before his time.
- 4Variants
History[edit]
The screw pump is the oldest positive displacement pump.[1] The first records of a water screw, or screw pump, dates back to Ancient Egypt before the 3rd century BC.[1][2] The Egyptian screw, used to lift water from the Nile, was composed of tubes wound round a cylinder; as the entire unit rotates, water is lifted within the spiral tube to the higher elevation. A later screw pump design from Egypt had a spiral groove cut on the outside of a solid wooden cylinder and then the cylinder was covered by boards ot sheets of metal closely covering the surfaces between the grooves.[1]
Some researchers have postulated this as being the device used to irrigate the Hanging Gardens of Babylon, one of the Seven Wonders of the Ancient World. A cuneiform inscription of Assyrian King Sennacherib (704–681 BC) has been interpreted by Stephanie Dalley[3] to describe casting water screws in bronze some 350 years earlier. This is consistent with classical author Strabo, who describes the Hanging Gardens as irrigated by screws.[4]
The screw pump was later introduced from Egypt to Greece.[1] It was described by Archimedes,[5] on the occasion of his visit to Egypt, circa 234 BC.[6] This tradition may reflect only that the apparatus was unknown to the Greeks before Hellenistic times.[5] Archimedes never claimed credit for its invention, but was attributed to him 200 years later by Diodorus, who believed that Archimedes invented the screw pump in Egypt.[1] Depictions of Greek and Roman water screws show them being powered by a human treading on the outer casing to turn the entire apparatus as one piece, which would require that the casing be rigidly attached to the screw.
German engineer Konrad Kyeser equipped the Archimedes screw with a crank mechanism in his Bellifortis (1405). This mechanism quickly replaced the ancient practice of working the pipe by treading.[7]
Design[edit]
The Archimedes screw consists of a screw (a helical surface surrounding a central cylindrical shaft) inside a hollow pipe. The screw is usually turned by windmill, manual labor, cattle, or by modern means, such as a motor. As the shaft turns the bottom end scoops up a volume of water. This water is then pushed up the tube by the rotating helicoid until it pours out from the top of the tube.
The contact surface between the screw and the pipe does not need to be perfectly watertight, as long as the amount of water being scooped with each turn is large compared to the amount of water leaking out of each section of the screw per turn. If water from one section leaks into the next lower one, it will be transferred upwards by the next segment of the screw.
In some designs, the screw is fused to the casing and they both rotate together, instead of the screw turning within a stationary casing. The screw could be sealed to the casing with pitch resin or other adhesive, or the screw and casing could be cast together as a single piece in bronze.
The design of the everyday Greek and Roman water screw, in contrast to the heavy bronze device of Sennacherib, with its problematic drive chains, has a powerful simplicity. A double or triple helix was built of wood strips (or occasionally bronze sheeting) around a heavy wooden pole. A cylinder was built around the helices using long, narrow boards fastened to their periphery and waterproofed with pitch.[4]
Uses[edit]
The screw was used predominately for the transport of water to irrigation systems and for dewatering mines or other low-lying areas. It was used for draining land that was underneath the sea in the Netherlands and other places in the creation of polders.
Archimedes screws are used in sewage treatment plants because they cope well with varying rates of flow and with suspended solids. An auger in a snow blower or grain elevator is essentially an Archimedes screw. Many forms of axial flow pump basically contain an Archimedes screw.
The principle is also found in pescalators, which are Archimedes screws designed to lift fish safely from ponds and transport them to another location. This technology is used primarily at fish hatcheries, where it is desirable to minimize the physical handling of fish.
An Archimedes screw was used in the successful 2001 stabilization of the Leaning Tower of Pisa. Small amounts of subsoil saturated by groundwater removed from far below the north side of the tower, and the weight of the tower itself corrected the lean.Archimedes screws are also used in chocolate fountains.
Variants[edit]
An Archimedes screw seen on a combine harvester
A screw conveyor is an Archimedes screw contained within a tube and turned by a motor so as to deliver material from one end of the conveyor to the other. It is particularly suitable for transport of granular materials such as plastic granules used in injection molding, and cereal grains. It may also be used to transport liquids. In industrial control applications the conveyor may be used as a rotary feeder or variable rate feeder to deliver a measured rate or quantity of material into a process.
A variant of the Archimedes screw can also be found in some injection molding machines, die casting machines and extrusion of plastics, which employ a screw of decreasing pitch to compress and melt the material. It is also used in a rotary-screw air compressor. On a much larger scale, Archimedes's screws of decreasing pitch are used for the compaction of waste material.
Reverse action[edit]
If water is fed into the top of an Archimedes screw, it will force the screw to rotate. The rotating shaft can then be used to drive an electric generator. Such an installation has the same benefits as using the screw for pumping: the ability to handle very dirty water and widely varying rates of flow at high efficiency. Settle Hydro and Torrs Hydro are two reverse screw micro hydro schemes operating in England. The screw works well as a generator at low heads, commonly found in English rivers, including the Thames, powering Windsor Castle.[8]
In 2017, the first reverse screw hydropower in the United States opened in Meriden, Connecticut.[9][10] The Meriden project was built and is operated by New England Hydropower having a nameplate capacity of 193 kW and a capacity factor of approximately 55% over a 5-year running period.
See also[edit]
- SS Archimedes – the first steamship driven by a screw propeller.
Notes[edit]
- ^ abcdefStewart, Bobby Alton; Terry A. Howell (2003). Encyclopedia of water science. USA: CRC Press. p. 759. ISBN0-8247-0948-9.
- ^'Screw'. Encyclopædia Britannica online. The Encyclopaedia Britannica Co. 2011. Retrieved 2011-03-24.
- ^Stephanie Dalley, The Mystery of the Hanging Garden of Babylon: an elusive World Wonder traced, (2013), OUP ISBN978-0-19-966226-5
- ^ abDalley, Stephanie; Oleson, John Peter (2003). 'Sennacherib, Archimedes, and the Water Screw: The Context of Invention in the Ancient World'. Technology and Culture. 44 (1): 1–26. doi:10.1353/tech.2003.0011.
- ^ abOleson 2000, pp. 242–251
- ^Haven, Kendall F. (2006). One hundred greatest science inventions of all time. USA: Libraries Unlimited. pp. 6–. ISBN1-59158-264-4.
- ^White, Jr. 1962, pp. 105, 111, 168
- ^BBC. 'Windsor Castle water turbine installed on River Thames'bbc.com, 20 September 2011. Retrieved: 19 October 2017.
- ^HLADKY, GREGORY B. 'Archimedes Screw Being Used To Generate Power At Meriden Dam'. courant.com. Retrieved 2017-08-01.
- ^'Meriden power plant uses Archimedes Screw Turbine'. Retrieved 2017-08-01.
References[edit]
- P. J. Kantert: 'Manual for Archimedean Screw Pump', Hirthammer Verlag 2008, ISBN978-3-88721-896-6.
- P. J. Kantert: 'Praxishandbuch Schneckenpumpe', Hirthammer Verlag 2008, ISBN978-3-88721-202-5.
- Oleson, John Peter (1984), Greek and Roman mechanical water-lifting devices. The History of a Technology, Dordrecht: D. Reidel, ISBN90-277-1693-5
- Oleson, John Peter (2000), 'Water-Lifting', in Wikander, Örjan (ed.), Handbook of Ancient Water Technology, Technology and Change in History, 2, Leiden, pp. 217–302 (242–251), ISBN90-04-11123-9
- Nuernbergk, D. and Rorres C.: „An Analytical Model for the Water Inflow of an Archimedes Screw Used in Hydropower Generation', ASCE Journal of Hydraulic Engineering, Published: 23 July 2012
- Nuernbergk D. M.: 'Wasserkraftschnecken – Berechnung und optimaler Entwurf von archimedischen Schnecken als Wasserkraftmaschine', Verlag Moritz Schäfer, Detmold, 1. Edition. 2012, 272 papes, ISBN978-3-87696-136-1
- Rorres C.: 'The turn of the Screw: Optimum design of an Archimedes Screw', ASCE Journal of Hydraulic Engineering, Volume 126, Number 1, Jan.2000, pp. 72–80
- Nagel, G.; Radlik, K.: Wasserförderschnecken – Planung, Bau und Betrieb von Wasserhebeanlagen; Udo Pfriemer Buchverlag in der Bauverlag GmbH, Wiesbaden, Berlin (1988)
- White, Jr., Lynn (1962), Medieval Technology and Social Change, Oxford: At the Clarendon Press
External links[edit]
Wikisource has the text of the 1911 Encyclopædia Britannica article Archimedes, Screw of. |
- Media related to Archimedes' screw at Wikimedia Commons
- 'Archimedean Screw' by Sándor Kabai, Wolfram Demonstrations Project, 2007.
Retrieved from 'https://en.wikipedia.org/w/index.php?title=Archimedes%27_screw&oldid=917822002'
From Wikipedia, the free encyclopedia
Archimedes' screw was operated by hand and could raise water efficiently An Archimedes screw in Huseby south of Växjö Sweden Archimedes' screw Roman screw used to dewater mines in Spain Modern Archimedes screws which have replaced some of the windmills used to drain the polders at Kinderdijk in Holland |
The Archimedes screw, also known as Archimedes' screw, the Archimedean screw or the screwpump is a machine historically used for transferring water from a low-lying body of water into irrigation ditches. It was one of several inventions and discoveries traditionally attributed to Archimedes in the 3rd century BC, though this has been debated in modern times.
Contents
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Design
The Archimedes' Screw consists of a screw inside a hollow pipe. The screw is turned usually by a windmill or by manual labour. As the bottom end of the tube turns, it scoops up a volume of water. This amount of water will slide up in the spiral tube as the shaft is turned, until it finally pours out from the top of the tube and feeds the irrigation systems.It was mostly used for draining water out of mines.
The contact surface between the screw and the pipe does not need to be perfectly water-tight because of the relatively large amount of water being scooped at each turn with respect to the angular frequency and angular speed of the screw. Also, water leaking from the top section of the screw leaks into the previous one and so on, so a sort of mechanical equilibrium is achieved while using the machine, thus preventing a decrease in mechanical efficiency.
In some designs, the screw is fixed to the casing and they rotate together instead of the screw turning within a stationary casing. A screw could be sealed with Pitch resin or some other adhesive to its casing, or, cast as a single piece in bronze, as some researchers have postulated as being the devices used to irrigate the Hanging Gardens of Babylon, one of the Seven Wonders of the Ancient World. Depictions of Greek and Roman water screws show the screws being powered by a human treading on the outer casing to turn the entire apparatus as one piece, which would require that the casing be rigidly attached to the screw.
Vertical Archimedes Screw
“ | The design of the everyday Greek and Roman water screw, in contrast to the heavy bronze device of Sennacherib, with its problematic drive chains, has a powerful simplicity. A double or triple helix was built of wood strips (or occasionally bronze sheeting) around a heavy wooden pole. A cylinder was built around the helices using long, narrow boards fastened to their periphery and waterproofed with pitch[1] | ” |
Uses
Along with transferring water to irrigation ditches, this device was also used for reclaiming land from under sea level in the Netherlands and other places in the creation of polders. A part of the sea would be enclosed and the water would be pushed up out of the enclosed area, starting the process of draining the land for use in farming. Depending on the length and diameter of the screws, more than one machine could be used to successively lift the same water.
Archimedes screws are used in sewage treatment plants because they cope well with varying rates of flow and with suspended solids. An auger in a snow blower or grain elevator is essentially an Archimedes screw.
Archimedes Screw Pdf
The principle is also found in pescalators, which are Archimedes screws designed to lift fish safely from ponds and transport them to another location. This technology is primarily used at fish hatcheries as it is desirable to minimize the physical handling of fish.
The invention of the water-screw is traditionally credited to Archimedes of Syracuse in the 3rd century BC.[2] The Assyriologist historian Stephanie Dalley, however, attributes its invention to 6th century BC Assyria, during the time of King Sennacherib.[3] John Peter Oleson, on the other hand, is of the opinion that there is a 'total lack of any literary and archaeological evidence for the existence of the water-screw before ca. 250 BC'.[4] A screw can be thought of as an inclined plane wrapped around a cylinder.
It can also be found in some injection moulding machines, die casting machines and extrusion of plastics to 'pump' out the molten liquid.
Variants
An Archimedes screw seen on a combine
Main article: Screw conveyor
Archimedes Screw Pump Design Manual Diagram
A screw conveyor is an Archimedes' screw contained within a tube and turned by a motor so as to deliver material from one end of the conveyor to the other. It is particularly suitable for transport of granular materials such as plastic granules used in injection moulding, and cereal grains. It may also be used to transport liquids. In industrial control applications the conveyor may be used as a rotary feeder or variable rate feeder to deliver a measured rate or quantity of material into a process.
Reverse action
If water is poured into the top of an Archimedes' screw, it will force the screw to rotate. The rotating shaft can then be used to drive an electric generator. Such an installation has the same benefits as using the screw for pumping: the ability to handle very dirty water and widely varying rates of flow. Settle Hydro and Torrs Hydro are two reverse screw micro hydro schemes operating in England.
See also
- Spiral pump[5]
- water screw
Footnotes
- ^Online copy of Dalley/Oleson article
- ^Oleson 2000, pp. 242–251
- ^ Stephanie Dalley and John Peter Oleson (January 2003). 'Sennacherib, Archimedes, and the Water Screw: The Context of Invention in the Ancient World', Technology and Culture44 (1).
- ^Oleson 1984, pp. 292
- ^Spiral pump related to archimedes screw
References
- Oleson, John Peter (2000), 'Water-Lifting', in Wikander, Örjan, Handbook of Ancient Water Technology, Technology and Change in History, 2, Leiden, pp. 217–302 (242–251), ISBN 90-04-11123-9
- Oleson, John Peter (1984), Greek and Roman mechanical water-lifting devices. The History of a Technology, Dordrecht: D. Reidel, ISBN 90-277-1693-5
- P. J. Kantert: „Manual for Archimedean Screw Pump“, Hirthammer Verlag 2008, ISBN 978-3-88721-896-6.
- P. J. Kantert: „Praxishandbuch Schneckenpumpe“, Hirthammer Verlag 2008, ISBN 978-3-88721-202-5.
External links
- Technology and Culture Volume 44, Number 1, January 2003 (PDF) Dalley, Stephanie. Oleson, John Peter. 'Sennacherib, Archimedes, and the Water Screw: The Context of Invention in the Ancient World'
- Plywood archimedean screw water pump, how to build a functioning Archimedes screw pump (Archived 2009-10-25)
- 'Archimedean Screw' by Sándor Kabai, Wolfram Demonstrations Project, 2007.