 The rotor of the small water turbine A water turbine is a rotary engine that takes energy from moving water. Wikipedia does not have an article with this exact name. ...
Wikipedia does not have an article with this exact name. ...
A Bonneville Dam Kaplan turbine after 61 years of service The Kaplan turbine is a propeller-type water turbine that has adjustable blades. ...
This article is about machines that produce electricity. ...
Image File history File links Metadata Size of this preview: 685 × 599 pixelsFull resolution (2304 × 2016 pixel, file size: 510 KB, MIME type: image/jpeg) GPL applies to the picture only and is granted if somebody would think about creating icons based on this image. ...
Image File history File links Metadata Size of this preview: 685 × 599 pixelsFull resolution (2304 × 2016 pixel, file size: 510 KB, MIME type: image/jpeg) GPL applies to the picture only and is granted if somebody would think about creating icons based on this image. ...
For other uses, see Engine (disambiguation). ...
Water turbines were developed in the nineteenth century and were widely used for industrial power prior to electrical grids. Now they are mostly used for electric power generation. They harness a clean and renewable energy source. Electric power transmission is the second process in the delivery of electricity to consumers. ...
For delivered electrical power, see Electrical power industry. ...
Renewable energy effectively utilizes natural resources such as sunlight, wind, tides and geothermal heat, which are naturally replenished. ...
History
Swirl Water wheels have been used for thousands of years for industrial power. Their main shortcoming is size, which limits the flow rate and head that can be harnessed. An overshot water wheel standing 42 feet high powers the Old Mill at Berry College in Rome, Georgia A water wheel (also waterwheel, Norse mill, Persian wheel or noria) is a hydropower system; a system for extracting power from a flow of water. ...
In fluid dynamics, head refers to the constant right hand side in the incompressible steady version of Bernoullis equation. ...
The migration from water wheels to modern turbines took about one hundred years. Development occurred during the Industrial revolution, using scientific principles and methods. They also made extensive use of new materials and manufacturing methods developed at the time. A Watt steam engine, the steam engine that propelled the Industrial Revolution in Britain and the world. ...
The word turbine was coined by the French engineer Claude Bourdin in the early 19th century and is derived from the Latin word for "whirling" or a "vortex". The main difference between early water turbines and water wheels is a swirl component of the water which passes energy to a spinning rotor. This additional component of motion allowed the turbine to be smaller than a water wheel of the same power. They could process more water by spinning faster and could harness much greater heads. (Later, impulse turbines were developed which didn't use swirl). A Siemens steam turbine with the case opened. ...
Time line
 A Francis turbine runner, rated at nearly one million hp (750 MW), being installed at the Grand Coulee Dam
 A propeller-type runner rated 28,000 hp (21 MW) Ján Andrej Segner developed a reactive water turbine in the mid-1700s. It had a horizontal axis and was a precursor to modern water turbines. It is a very simple machine that is still produced today for use in small hydro sites. Segner worked with Euler on some of the early mathematical theories of turbine design. Download high resolution version (800x702, 99 KB)A water turbine at the Grand Coulee Dam. ...
Download high resolution version (800x702, 99 KB)A water turbine at the Grand Coulee Dam. ...
Francis turbine (courtsey Voith-Siemens). ...
This article is about a unit of measurement. ...
Image File history File links A fixed-blade turbine runner 15 feet 10 inches (4826 mm) diameter rated 28000 HP (20880 kW). ...
Image File history File links A fixed-blade turbine runner 15 feet 10 inches (4826 mm) diameter rated 28000 HP (20880 kW). ...
Johann Andreas Segner (in Slovak: Ján Andrej Segner, in Hungarian: Segner János András, 9 October 1704, Pressburg (today: Bratislava), Kingdom of Hungary (today: Slovakia) - 5 October 1777, Halle) was a Carpatho-German mathematician, physicist, doctor. ...
Leonhard Euler aged 49 (oil painting by Emanuel Handmann, 1756) Leonhard Euler (April 15, 1707 - September 18, 1783) (pronounced oiler) was a Swiss mathematician and physicist. ...
In 1820, Jean-Victor Poncelet developed an inward-flow turbine. Jean-Victor Poncelet (July 1, 1788 – December 22, 1867) was a mathematician and engineer who did much to revive projective geometry. ...
In 1826 Benoit Fourneyron developed an outward-flow turbine. This was an efficient machine (~80%) that sent water through a runner with blades curved in one dimension. The stationary outlet also had curved guides. Bénoit Fourneyron was born in Saint-Étienne, France in 1802. ...
In 1844 Uriah A. Boyden developed an outward flow turbine that improved on the performance of the Fourneyron turbine. Its runner shape was similar to that of a Francis turbine. Uriah Atherton Boyden (February 17, 1804 – October 17, 1879) was a Boston inventor and mechanical engineer. ...
Francis turbine (courtsey Voith-Siemens). ...
In 1849, James B. Francis improved the inward flow reaction turbine to over 90% efficiency. He also conducted sophisticated tests and developed engineering methods for water turbine design. The Francis turbine, named for him, is the first modern water turbine. It is still the most widely used water turbine in the world today.The Francis turbine is also called as Radial flow Turbine.In which water flows from outercircumference towards the centre of runner. James Bicheno Francis (May 18, 1815 – September 18, 1892) was a British-American engineer. ...
Inward flow water turbines have a better mechanical arrangement and all modern reaction water turbines are of this design. As the water swirls inward, it accelerates, and transfers energy to the runner. Water pressure decreases to atmospheric, or in some cases subatmospheric, as the water passes through the turbine blades and loses energy.
Around 1890, the modern fluid bearing was invented, now universally used to support heavy water turbine spindles. As of 2002, fluid bearings appear to have a mean time between failures of more than 1300 years. Fluid bearings are bearings which solely support the bearings loads on a thin layer of liquid or gas. ...
Mean time between failures (MTBF) is the mean (average) time between failures of a system, the reciprocal of the failure rate in the special case when the failure rate is constant. ...
Around 1913, Victor Kaplan created the Kaplan turbine, a propeller-type machine. It was an evolution of the Francis turbine but revolutionized the ability to develop low-head hydro sites. Viktor Kaplan Viktor Kaplan (November 27, 1876 in Mürzzuschlag, Austria - August 23, 1934 in Unterach am Attersee, Austria) was an Austrian engineer and the inventor of the Kaplan turbine. ...
A Bonneville Dam Kaplan turbine after 61 years of service The Kaplan turbine is a propeller-type water turbine that has adjustable blades. ...
A new concept
 Figure from Pelton's original patent (October 1880) -
Main article: Pelton wheel All common water machines until the late 19th century (including water wheels) were reaction machines; water pressure head acted on the machine and produced work. A reaction turbine needs to fully contain the water during energy transfer. Image File history File links No higher resolution available. ...
Image File history File links No higher resolution available. ...
Pelton wheel from Walchensee, Germany hydro power station Figure from Peltons original patent (October 1880) Plan view of a Pelton turbine installation (courtesy Voith Siemens Hydro Power Generation). ...
In 1866, California millwright Samuel Knight invented a machine that worked off a completely different concept[1][2]. Inspired by the high pressure jet systems used in hydraulic mining in the gold fields, Knight developed a bucketed wheel which captured the energy of a free jet, which had converted a high head (hundreds of vertical feet in a pipe or penstock) of water to kinetic energy. This is called an impulse or tangential turbine. The water's velocity, roughly twice the velocity of the bucket periphery, does a u-turn in the bucket and drops out of the runner at low velocity. Penstocks at the Grand Coulee Dams third powerhouse. ...
In 1879, Lester Pelton(1829-1908), experimenting with a Knight Wheel, developed a double bucket design, which exhausted the water to the side, eliminating some energy loss of the Knight wheel which exhausted some water back against the center of the wheel. In about 1895, William Doble improved on Pelton's half-cylindrical bucket form with an elliptical bucket that included a cut in it to allow the jet a cleaner bucket entry. This is the modern form of the Pelton turbine which today achieves up to 92% efficiency. Pelton had been quite an effective promoter of his design and although Doble took over the Pelton company he did not change the name to Doble because it had brand name recognition. Lester Allan Pelton (1829 - March 14, 1908), was an American inventor who created the impulse water turbine. ...
Pelton wheel from Walchensee, Germany hydro power station Figure from Peltons original patent (October 1880) Plan view of a Pelton turbine installation (courtesy Voith Siemens Hydro Power Generation). ...
Turgo and Crossflow turbines were later impulse designs. Turgo turbine and generator The Turgo turbine is an impulse water turbine designed for medium head applications. ...
Banki turbine - Wikipedia /**/ @import /w/skins-1. ...
Theory of operation Flowing water is directed on to the blades of a turbine runner, creating a force on the blades. Since the runner is spinning, the force acts through a distance (force acting through a distance is the definition of work). In this way, energy is transferred from the water flow to the turbine. In physics, mechanical work is the amount of energy transferred by a force. ...
Water turbines are divided into two groups; reaction turbines and impulse turbines. A reaction is the following: In physics, a reaction (physics) is defined by Newtons third law: For every action there is an equal and opposite reaction. The idea that any given force has a pair or opposite force. ...
For other uses, see Impulse (disambiguation). ...
The precise shape of water turbine blades is a function of the supply pressure of water, and the type of impeller selected.
Reaction turbines Reaction turbines are acted on by water, which changes pressure as it moves through the turbine and gives up its energy. They must be encased to contain the water pressure (or suction), or they must be fully submerged in the water flow.
Newton's third law describes the transfer of energy for reaction turbines. Newtons laws of motion are the three scientific laws which Isaac Newton discovered concerning the behaviour of moving bodies. ...
Most water turbines in use are reaction turbines. They are used in low and medium head applications.
Impulse turbines Impulse turbines change the velocity of a water jet. The jet impinges on the turbine's curved blades which change the direction of the flow. The resulting change in momentum (impulse) causes a force on the turbine blades. Since the turbine is spinning, the force acts through a distance (work) and the diverted water flow is left with diminished energy. This article is about velocity in physics. ...
For other uses, see Impulse (disambiguation). ...
Prior to hitting the turbine blades, the water's pressure (potential energy) is converted to kinetic energy by a nozzle and focused on the turbine. No pressure change occurs at the turbine blades, and the turbine doesn't require a housing for operation. Potential energy can be thought of as energy stored within a physical system. ...
The cars of a roller coaster reach their maximum kinetic energy when at the bottom of their path. ...
Rocket Nozzle A nozzle is a mechanical device designed to control the characteristics of a fluid flow as it exits from an enclosed chamber into some medium. ...
Newton's second law describes the transfer of energy for impulse turbines. Newtons laws of motion are the three scientific laws which Isaac Newton discovered concerning the behaviour of moving bodies. ...
Impulse turbines are most often used in very high head applications.
Power The power available in a stream of water is; In physics, power (symbol: P) is the rate at which work is performed or energy is transmitted, or the amount of energy required or expended for a given unit of time. ...
where:
- P = power (J/s or watts)
- η = turbine efficiency
- ρ = density of water (kg/m³)
- g = acceleration of gravity (9.81 m/s²)
- h = head (m). For still water, this is the difference in height between the inlet and outlet surfaces. Moving water has an additional component added to account for the kinetic energy of the flow. The total head equals the pressure head plus velocity head.
 = flow rate (m³/s)
Pumped storage Some water turbines are designed for Pumped storage hydroelectricity. They can reverse flow and operate as a pump to fill a high reservoir during off-peak electrical hours, and then revert to a turbine for power generation during peak electrical demand. This type of turbine is usually a Deriaz or Francis in design. Diagram of the TVA pumped storage facility at Racoon Mountain Pumped storage hydroelectricity is a method of storing and producing electricity to supply high peak demands. ...
Francis turbine (courtsey Voith-Siemens). ...
Efficiency Large modern water turbines operate at mechanical efficiencies greater than 90% (not to be confused with thermodynamic efficiency). In physics, mechanical efficiency is the effectiveness of a machine and is defined as Efficiency is often indicated by a percentage, the efficiency of an ideal machine is 100%. Due to the fact that energy cannot emerge from nothing and the Second law of thermodynamics which states that the quality...
Thermodynamic efficiency (e) is defined as: where W is the absolute value of the work done in one thermodynamic cycle. ...
Types of water turbines Reaction turbines: Impulse turbines: Francis turbine (courtsey Voith-Siemens). ...
A Bonneville Dam Kaplan turbine after 61 years of service The Kaplan turbine is a propeller-type water turbine that has adjustable blades. ...
http://www. ...
An overshot water wheel standing 42 feet high powers the Old Mill at Berry College in Rome, Georgia A water wheel (also waterwheel, Norse mill, Persian wheel or noria) is a hydropower system; a system for extracting power from a flow of water. ...
Pelton wheel from Walchensee, Germany hydro power station Figure from Peltons original patent (October 1880) Plan view of a Pelton turbine installation (courtesy Voith Siemens Hydro Power Generation). ...
Turgo turbine and generator The Turgo turbine is an impulse water turbine designed for medium head applications. ...
Banki turbine - Wikipedia /**/ @import /w/skins-1. ...
Design and application Turbine selection is based mostly on the available water head, and less so on the available flow rate. In general, impulse turbines are used for high head sites, and reaction turbines are used for low head sites. Kaplan turbines with adjustable blade pitch are well-adapted to wide ranges of flow or head conditions, since their peak efficiency can be achieved over a wide range of flow conditions. Water turbine application chart I created this chart and release it under the GNU licence. ...
Small turbines (mostly under 10 MW) may have horizontal shafts, and even fairly large bulb-type turbines up to 100 MW or so may be horizontal. Very large Francis and Kaplan machines usually have vertical shafts because this makes best use of the available head, and makes installation of a generator more economical. Pelton wheels may be either vertical or horizontal shaft machines because the size of the machine is so much less than the available head. Some impulse turbines use multiple water jets per runner to increase specific speed and balance shaft thrust.
Typical range of heads A Bonneville Dam Kaplan turbine after 61 years of service The Kaplan turbine is a propeller-type water turbine that has adjustable blades. ...
Francis turbine (courtsey Voith-Siemens). ...
Pelton wheel from Walchensee, Germany hydro power station Figure from Peltons original patent (October 1880) Plan view of a Pelton turbine installation (courtesy Voith Siemens Hydro Power Generation). ...
Turgo turbine and generator The Turgo turbine is an impulse water turbine designed for medium head applications. ...
Specific speed The specific speed, ns , of a turbine characterizes the turbine's shape in a way that is not related to its size. This allows a new turbine design to be scaled from an existing design of known performance. The specific speed is also the main criteria for matching a specific hydro site with the correct turbine type.
The specific speed of a turbine can also be defined as the speed of an ideal, geometrically similar turbine, which yields one unit of power for one unit of head.
The specific speed of a turbine is given by the manufacturer (along with other ratings) and will always refer to the point of maximum efficiency. This allows accurate calculations to be made of the turbine's performance for a range of heads and flows.
 (dimensioned parameter), n = rpm  (dimensionless parameter), In dimensional analysis, a dimensionless number (or more precisely, a number with the dimensions of 1) is a pure number without any physical units. ...
- Ω = angular velocity (radians/second)
Example; Given a flow and head for a specific hydro site, and the rpm requirement of the generator, calculate the specific speed. The result is the main criteria for turbine selection.
The specific speed is also the starting point for analytical design of a new turbine. Once the desired specific speed is known, basic dimensions of the turbine parts can be easily calculated.
Affinity Laws allow the output of a turbine to be predicted based on model tests. A miniature replica of a proposed design, about one foot (0.3 m) in diameter, can be tested and the laboratory measurements applied to the final application with high confidence. Affinity laws are derived by requiring similitude between the test model and the application. The affinity laws express the mathematical relationship between the several variables involved in pump performance. ...
A full scale X-43 Wind tunnel test. ...
Flow through the turbine is controlled either by a large valve or by wicket gates arranged around the outside of the turbine runner. Differential head and flow can be plotted for a number of different values of gate opening, producing a hill diagram used to show the efficiency of the turbine at varying conditions.
Runaway speed The runaway speed of a water turbine is its speed at full flow, and no shaft load. The turbine will be designed to survive the mechanical forces of this speed. The manufacturer will supply the runaway speed rating.
Maintenance Turbines are designed to run for decades with very little maintenance of the main elements; overhaul intervals are on the order of several years. Maintenance of the runners and parts exposed to water include removal, inspection, and repair of worn parts. Image File history File linksMetadata Download high resolution version (2304x1728, 884 KB) Summary Licensing File links The following pages link to this file: Cavitation Water turbine Metadata This file contains additional information, probably added from the digital camera or scanner used to create or digitize it. ...
Image File history File linksMetadata Download high resolution version (2304x1728, 884 KB) Summary Licensing File links The following pages link to this file: Cavitation Water turbine Metadata This file contains additional information, probably added from the digital camera or scanner used to create or digitize it. ...
Francis turbine (courtsey Voith-Siemens). ...
Cavitating propeller model in a water tunnel experiment High speed jet of fluid impact on a fixed surface. ...
In materials science, fatigue is the progressive, localised, and permanent structural damage that occurs when a material is subjected to cyclic or fluctuating strains at nominal stresses that have maximum values less than (often much less than) the static yield strength of the material. ...
Normal wear and tear includes pitting from cavitation, fatigue cracking, and abrasion from suspended solids in the water. Steel elements are repaired by welding, usually with stainless steel rod. Damaged areas are cut or ground out, then welded back up to their original or an improved profile. Old turbine runners may have a significant amount of stainless steel added this way by the end of their lifetime. Elaborate welding procedures may be used to achieve the highest quality repairs.[3] Cavitating propeller model in a water tunnel experiment High speed jet of fluid impact on a fixed surface. ...
The 630 foot (192 m) high, stainless-clad (type 304) Gateway Arch defines St. ...
Welding is a fabrication process that joins materials, usually metals or thermoplastics, by causing coalescence. ...
Other elements requiring inspection and repair during overhauls include bearings, packing box and shaft sleeves, servomotors, cooling systems for the bearings and generator coils, seal rings, wicket gate linkage elements and all surfaces. [4]
Bearing is the following: Often, bearing is the state of having something as a quality, characteristic, or permanent attribute. ...
Environmental impact Water turbines are generally considered a clean power producer, as the turbine causes essentially no change to the water. They use a renewable energy source and are designed to operate for decades. They produce significant amounts of the world's electrical supply.
Historically there have also been negative consequences, mostly associated with the dams normally required for power production. Dams alter the natural ecology of rivers, potentially killing fish, stopping migrations, and disrupting peoples' livelihoods. For example, American Indian tribes in the Pacific Northwest had livelihoods built around salmon fishing, but aggressive dam-building destroyed their way of life. Dams also cause less obvious, but potentially serious consequences, including increased evaporation of water (especially in arid regions), build up of silt behind the dam, and changes to water temperature and flow patterns. Some people[who?] believe that it is possible to construct hydropower systems that divert fish and other organisms away from turbine intakes without significant damage or loss of power; historical performance of diversion structures has been poor. In the United States, it is now illegal to block the migration of fish so fish ladders must be provided by dam builders. The actual performance of fish ladders is often poor. Many types of fish undertake migrations on a regular basis, on time scales ranging from daily to annual, and with distances ranging from a few meters to thousands of kilometers. ...
A Sioux in traditional dress including war bonnet, circa 1908. ...
The Pacific Northwest from space The Pacific Northwest, abbreviated PNW, or PacNW is a region in the northwest of North America. ...
For other uses, see Salmon (disambiguation). ...
Fishermen in the harbor of Kochi, India. ...
Pool-and-weir fish ladder at Bonneville Dam on the Columbia River Fishways, most commonly referred to as fish ladders but also known as fish passes, are structures placed on or around man-made barriers (such as dams and weirs) to assist the natural migration of diadromous fishes. ...
See also
 | Sustainable development Portal | Image File history File links Sustainable_development. ...
Banki turbine - Wikipedia /**/ @import /w/skins-1. ...
The Gorlov helical turbine is a water turbine based on the Darrieus turbine, which was altered to have helical blades/foils and thus a constant (as opposed to intermittent) optimal angle of attack in a current. ...
Hydroelectricity is electricity produced by hydropower. ...
Undershot water wheels on the Orontes River in Hama, Syria Saint Anthony Falls Hydropower or hydraulic power is the force or energy of moving water. ...
A Siemens steam turbine with the case opened. ...
An overshot water wheel standing 42 feet high powers the Old Mill at Berry College in Rome, Georgia A water wheel (also waterwheel, Norse mill, Persian wheel or noria) is a hydropower system; a system for extracting power from a flow of water. ...
References - ^ W. A. Doble, The Tangential Water Wheel, Transactions of the American Institute of Mining Engineers, Vol. XXIX, 1899.
- ^ W. F. Durrand, The Pelton Water Wheel, Stanford University, Mechanical Engineering, 1939.
- ^ Cline, Roger:Mechanical Overhaul Procedures for Hydroelectric Units (Facilities Instructions, Standards, and Techniques, Volume 2-7); United States Department of the Interior Bureau of Reclamation, Denver, Colorado, July 1994 (800KB pdf).
- ^ United States Department of the Interior Bureau of Reclamation; Duncan, William (revised April 1989): Turbine Repair (Facilities Instructions, Standards & Techniques, Volume 2-5) (1.5 MB pdf).
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