the archimedes screw?

Question

i'm doing a project about the archimedes screw and i need help! (obviously) can anybody give me the history of the archimedes screw? did other people propose any alternate solutions? anything u can give me about the archimedes screw (including the history) ANYTHING about it is accepted!!!!!! please and thank you!!!!!! =]

and please nothing from wikipedia because i've been there, done that and it helped a lot but i need more info. thanks!!!!!

Answer 1

Archimedes' screw
From Wikipedia, the free encyclopedia


Archimedes' screw, Archimedean screw, or 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, but recent research has shown that an earlier form of this screw was first used by Sennacherib, King of Assyria, for the water systems at the Hanging Gardens of Babylon and Nineveh in the 7th century BC.[1]





[edit] Workings

Screw Cascade in Southern EuropeThe machine consists of a screw inside a hollow pipe. A screw can be thought of as an inclined plane (another simple machine) wrapped around a cylinder.

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.

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 in respect to the 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 equilibrium is achieved while using the machine, thus preventing a decrease in efficiency.

The "screw" does not necessarily need to turn inside the casing, but can be allowed to turn with it in one piece. A screw could be sealed with pitch 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 Nebuchadnezzar II's Hanging Gardens of Babylon. 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.

“ 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]
”

Modern Archimedes' Screws which have replaced some of the Windmills used to drain the polders at Kinderdijk in Holland.Along with transferring water to irrigation ditches, this device was also used for "stealing" 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.

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, where it is desirable to minimize the physical handling of fish.


[edit] Mathematics behind the screw
The slope of the outside of the screw's helical blades with respect to its sides is 2. This requires that the slope the screw makes with respect to a horizontal line be less than 2 (an angle of 63°) in order for the buckets or pockets of water to form. In the profile of the screw the projection of each helical blade consists of two sinusoidal curves with the same periods and phases. One has an amplitude equal to the radius of the outer cylinder and the other has an amplitude equal to the radius of the inner cylinder. The horizontal water level of each full bucket of water is tangent to the inner sinusoidal curve. Thus, if the equation on the inner sinusoidal curve is y = sin x, then the water level is tangent to it at x = arccos(−3/4) = 138.59°.


Main dimensions of a screwpumpd = diameter of centre tube
D = diameter of blades
β = angle of installation
H0 = civil head
H1 = difference of medium levels, effective head
H2 = maximum difference of medium levels, delivery head
H3 = hydraulic head
J = number of flights
L = length of helix
S = rise



One of the earliest kinds of pump, associated with the Greek mathematician Archimedes. It consists of an enormous spiral screw revolving inside a close-fitting cylinder. It is used, for example, to raise water for irrigation.

The lowest portion of the screw just dips into the water, and as the cylinder is turned a small quantity of water is scooped up. The inclination of the cylinder is such that at the next revolution the water is raised above the next thread, whilst the lowest thread scoops up another quantity. The successive revolutions, therefore, raise the water thread by thread until it emerges at the top of the cylinder.


born: 290 to 280 BC, Syracuse, Sicily
died: 212 or 211 BC, Syracuse, Sicily
Archimedes was a mathematician and inventor from ancient Greece. He discovered the relation between the surface and volume of a sphere and its circumscribing cyclinder (he had discovered pi). He then formulated a hydrostatic principle based on that mathmatical relationship called Archimedes' principle. He inventing the Archimedes screw - a screw-shaped machine or hydraulic screw that raised water from a lower to a higher level. Archimedes also invented the catupult, the lever, the compound pulley, and the burning mirror (a system of mirrors that burned the boots and ships of invading armies by focusing the sun's rays). Although Archimedes is credited with inventing the screw in the 3rd century BC, his screw was not like today's screw fastener but actually two other screw-type devices.


Archimedes' screw, a simple mechanical device believed to have been invented by Archimedes in the 3d cent. B.C. It consists of a cylinder inside of which a continuous screw, extending the length of the cylinder, forms a spiral chamber. By placing the lower end in water and revolving the screw, water is raised to the top. The principle is applied in machines used for drainage and irrigation, and also in some types of high-speed tools. It can also be applied for handling light, loose materials such as grain, sand, and ashes.



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Answer 2

Archimedes Screw History

Answer 3

tricky situation. seek into search engines like google. that could actually help!

Answer 4

I also want to ask the same question

Answer 5

Thankyou all for your answers and opinions.