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96-652: Turbinia was the first steam turbine -powered steamship . Built as an experimental vessel in 1894, and easily the fastest ship in the world at that time, Turbinia was demonstrated dramatically at the Spithead Navy Review in 1897 and set the standard for the next generation of steamships, the majority of which would be turbine powered. The vessel is currently located at the Discovery Museum in Newcastle upon Tyne , North East England , while her original powerplant

192-536: A d e E n e r g y   s u p p l i e d   p e r   s t a g e = U Δ V w Δ h {\displaystyle {\eta _{\mathrm {stage} }}={\frac {\mathrm {Work~done~on~blade} }{\mathrm {Energy~supplied~per~stage} }}={\frac {U\Delta V_{w}}{\Delta h}}} Where Δ h = h 2 − h 1 {\displaystyle \Delta h=h_{2}-h_{1}}

288-563: A quality near 90%. Non-condensing turbines are most widely used for process steam applications, in which the steam will be used for additional purposes after being exhausted from the turbine. The exhaust pressure is controlled by a regulating valve to suit the needs of the process steam pressure. These are commonly found at refineries, district heating units, pulp and paper plants, and desalination facilities where large amounts of low pressure process steam are needed. Reheat turbines are also used almost exclusively in electrical power plants. In

384-671: A Heat Engine) was published in Berlin in 1903. A further book Dampf und Gas-Turbinen (English: Steam and Gas Turbines) was published in 1922. The Brown-Curtis turbine , an impulse type, which had been originally developed and patented by the U.S. company International Curtis Marine Turbine Company, was developed in the 1900s in conjunction with John Brown & Company . It was used in John Brown-engined merchant ships and warships, including liners and Royal Navy warships. The present day manufacturing industry for steam turbines consists of

480-444: A common reduction gear, with a geared cruising turbine on one high-pressure turbine. The moving steam imparts both a tangential and axial thrust on the turbine shaft, but the axial thrust in a simple turbine is unopposed. To maintain the correct rotor position and balancing, this force must be counteracted by an opposing force. Thrust bearings can be used for the shaft bearings, the rotor can use dummy pistons, it can be double flow -

576-674: A complete reconstruction was undertaken. On 30 October 1994, 100 years after her launch, Turbinia was moved to Newcastle's Museum of Science and Engineering (later renamed the Discovery Museum) and put on display to the public in March 1996. Listed as part of the National Historic Fleet , in 2000, the vessel was the focal point of a year-long, £10.7 million redevelopment programme at the Discovery Museum. The gallery around Turbinia

672-400: A compound impulse turbine. The modern steam turbine was invented in 1884 by Charles Parsons , whose first model was connected to a dynamo that generated 7.5 kilowatts (10.1 hp) of electricity. The invention of Parsons' steam turbine made cheap and plentiful electricity possible and revolutionized marine transport and naval warfare. Parsons' design was a reaction type. His patent

768-456: A generator. Tandem compound are used where two or more casings are directly coupled together to drive a single generator. A cross compound turbine arrangement features two or more shafts not in line driving two or more generators that often operate at different speeds. A cross compound turbine is typically used for many large applications. A typical 1930s-1960s naval installation is illustrated below; this shows high- and low-pressure turbines driving

864-408: A reheat turbine, steam flow exits from a high-pressure section of the turbine and is returned to the boiler where additional superheat is added. The steam then goes back into an intermediate pressure section of the turbine and continues its expansion. Using reheat in a cycle increases the work output from the turbine and also the expansion reaches conclusion before the steam condenses, thereby minimizing

960-448: A row of moving blades, with multiple stages for compounding. This is also known as a Rateau turbine, after its inventor. A velocity-compounded impulse stage (invented by Curtis and also called a "Curtis wheel") is a row of fixed nozzles followed by two or more rows of moving blades alternating with rows of fixed blades. This divides the velocity drop across the stage into several smaller drops. A series of velocity-compounded impulse stages

1056-418: A scientific twist". Up to 380 children aged between 7 and 11, accompanied by adults, are invited to spend an evening performing fun "science based" activities and then spend the night sleeping in the museum galleries amongst the exhibits. In the morning, they're woken to breakfast and more science, watching a show before the end of the event. On the evening of the last Wednesday of every month (except December)

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1152-578: A screen measuring 24.3 by 16.8 metres, with both a dual IMAX with Laser projection system and a traditional IMAX 15/70mm film projector, and an IMAX 12-channel sound system. Visitors to the Who Am I? gallery can explore the science of who they are through intriguing objects, provocative artworks and hands-on exhibits. Energy Revolution: The Adani Green Energy Gallery explores how the world can generate and use energy more sustainably to urgently reduce carbon dioxide emissions from global energy systems and limit

1248-1371: A single stage impulse turbine). Therefore, the maximum value of stage efficiency is obtained by putting the value of U V 1 = 1 2 cos ⁡ α 1 {\displaystyle {\frac {U}{V_{1}}}={\frac {1}{2}}\cos \alpha _{1}} in the expression of η b {\displaystyle \eta _{b}} . We get: η b max = 2 ( ρ cos ⁡ α 1 − ρ 2 ) ( 1 + k c ) = 1 2 cos 2 ⁡ α 1 ( 1 + k c ) {\displaystyle {\eta _{b}}_{\text{max}}=2\left(\rho \cos \alpha _{1}-\rho ^{2}\right)(1+kc)={\frac {1}{2}}\cos ^{2}\alpha _{1}(1+kc)} . For equiangular blades, β 1 = β 2 {\displaystyle \beta _{1}=\beta _{2}} , therefore c = 1 {\displaystyle c=1} , and we get η b max = 1 2 cos 2 ⁡ α 1 ( 1 + k ) {\displaystyle {\eta _{b}}_{\text{max}}={\frac {1}{2}}\cos ^{2}\alpha _{1}(1+k)} . If

1344-500: A steam pressure drop and velocity increase as steam moves through the nozzles. Nozzles move due to both the impact of steam on them and the reaction due to the high-velocity steam at the exit. A turbine composed of moving nozzles alternating with fixed nozzles is called a reaction turbine or Parsons turbine . Except for low-power applications, turbine blades are arranged in multiple stages in series, called compounding , which greatly improves efficiency at low speeds. A reaction stage

1440-399: A total of nine propellers. In trials, this achieved a top speed of more than 34 knots (63 km/h; 39 mph), so that "the passengers aboard would be convinced beyond all doubt Turbinia was Charles Parsons' winning North Sea greyhound". The turbines were directly driven, as geared turbines were not introduced until 1910. Even after the introduction of geared turbines, efficiency of even

1536-401: A valve, or left uncontrolled. Extracted steam results in a loss of power in the downstream stages of the turbine. Induction turbines introduce low pressure steam at an intermediate stage to produce additional power. These arrangements include single casing, tandem compound and cross compound turbines. Single casing units are the most basic style where a single casing and shaft are coupled to

1632-399: Is a row of fixed nozzles followed by a row of moving nozzles. Multiple reaction stages divide the pressure drop between the steam inlet and exhaust into numerous small drops, resulting in a pressure-compounded turbine. Impulse stages may be either pressure-compounded, velocity-compounded, or pressure-velocity compounded. A pressure-compounded impulse stage is a row of fixed nozzles followed by

1728-547: Is appreciably less than V 2 {\displaystyle V_{2}} , we get Δ h ≈ 1 2 V 2 2 {\displaystyle {\Delta h}\approx {\frac {1}{2}}{V_{2}}^{2}} . Furthermore, stage efficiency is the product of blade efficiency and nozzle efficiency, or η stage = η b η N {\displaystyle \eta _{\text{stage}}=\eta _{b}\eta _{N}} . Nozzle efficiency

1824-458: Is called a pressure-velocity compounded turbine. By 1905, when steam turbines were coming into use on fast ships (such as HMS  Dreadnought ) and in land-based power applications, it had been determined that it was desirable to use one or more Curtis wheels at the beginning of a multi-stage turbine (where the steam pressure is highest), followed by reaction stages. This was more efficient with high-pressure steam due to reduced leakage between

1920-436: Is composed of different regions of composition. A uniform dispersion of the gamma-prime phase – a combination of nickel, aluminum, and titanium – promotes the strength and creep resistance of the blade due to the microstructure. Refractory elements such as rhenium and ruthenium can be added to the alloy to improve creep strength. The addition of these elements reduces the diffusion of the gamma prime phase, thus preserving

2016-422: Is connected to the casing and one set of rotating blades is connected to the shaft. The sets intermesh with certain minimum clearances, with the size and configuration of sets varying to efficiently exploit the expansion of steam at each stage. An impulse turbine has fixed nozzles that orient the steam flow into high speed jets. These jets contain significant kinetic energy, which is converted into shaft rotation by

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2112-436: Is considered to be an isentropic process , or constant entropy process, in which the entropy of the steam entering the turbine is equal to the entropy of the steam leaving the turbine. No steam turbine is truly isentropic, however, with typical isentropic efficiencies ranging from 20 to 90% based on the application of the turbine. The interior of a turbine comprises several sets of blades or buckets . One set of stationary blades

2208-470: Is given by η N = V 2 2 2 ( h 1 − h 2 ) {\displaystyle \eta _{N}={\frac {{V_{2}}^{2}}{2\left(h_{1}-h_{2}\right)}}} , where the enthalpy (in J/Kg) of steam at the entrance of the nozzle is h 1 {\displaystyle h_{1}} and the enthalpy of steam at

2304-666: Is located at the Science Museum in London. Charles Algernon Parsons invented the modern steam turbine in 1884, and having foreseen its potential to power ships, he set up the Parsons Marine Steam Turbine Company in 1897. To develop this, he had the experimental vessel Turbinia built in a light design of steel by the firm of Brown and Hood, based at Wallsend on Tyne in the North East of England . The Admiralty

2400-510: Is not 'greenwash'". There have been protests against the sponsorship; in May 2021, a group calling themselves 'Scientists for XR' ( Extinction Rebellion ) locked themselves to a mechanical tree inside the museum. The UK Student Climate Network carried out an overnight occupation in June 2021, and were threatened with arrest. In August 2021, members of Extinction Rebellion held a protest inside and outside

2496-594: Is not a priority in astern turbines, so only a few stages are used to save cost. A major challenge facing turbine design was reducing the creep experienced by the blades. Because of the high temperatures and high stresses of operation, steam turbine materials become damaged through these mechanisms. As temperatures are increased in an effort to improve turbine efficiency, creep becomes significant. To limit creep, thermal coatings and superalloys with solid-solution strengthening and grain boundary strengthening are used in blade designs. Protective coatings are used to reduce

2592-675: Is one of the funding partners of the museum's STEM Training Academy. Equinor's sponsorship of the Wonderlab exhibit was on the basis that the Science Museum would not make any statement to damage the oil firm's reputation. Shell has influenced how the museum presents climate change in its programme sponsored by the oil company. The museum has signed a gagging clause in its agreement with Shell not to "make any statement or issue any publicity or otherwise be involved in any conduct or matter that may reasonably be foreseen as discrediting or damaging

2688-444: Is the angular velocity of the turbine, then the blade speed is U = ω r {\displaystyle U=\omega r} . The power developed is then W = m ˙ U ( Δ V w ) {\displaystyle W={\dot {m}}U(\Delta V_{w})} . Blade efficiency ( η b {\displaystyle {\eta _{b}}} ) can be defined as

2784-421: Is the specific enthalpy drop of steam in the nozzle. By the first law of thermodynamics : h 1 + 1 2 V 1 2 = h 2 + 1 2 V 2 2 {\displaystyle h_{1}+{\frac {1}{2}}{V_{1}}^{2}=h_{2}+{\frac {1}{2}}{V_{2}}^{2}} Assuming that V 1 {\displaystyle V_{1}}

2880-480: Is to increase the relative velocity at the exit. Therefore, the relative velocity at the exit V r 2 {\displaystyle V_{r2}} is always greater than the relative velocity at the inlet V r 1 {\displaystyle V_{r1}} . Science Museum, London The Science Museum is a major museum on Exhibition Road in South Kensington , London. It

2976-603: The National Collections Centre , at the Science Museum Wroughton, in Wiltshire. The Science Museum has a dedicated library, and until the 1960s was Britain's National Library for Science, Medicine and Technology. It holds runs of periodicals, early books and manuscripts, and is used by scholars worldwide. It was, for a number of years, run in conjunction with the library of Imperial College , but in 2007

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3072-842: The Science Museum Group . The museum was founded in 1857 under Bennet Woodcroft from the collection of the Royal Society of Arts and surplus items from the Great Exhibition as part of the South Kensington Museum , together with what is now the Victoria and Albert Museum . It included a collection of machinery which became the Museum of Patents in 1858, and the Patent Office Museum in 1863. This collection contained many of

3168-528: The control volume is equal to the net time change of angular momentum flux through the control volume. The swirling fluid enters the control volume at radius r 1 {\displaystyle r_{1}} with tangential velocity V w 1 {\displaystyle V_{w1}} and leaves at radius r 2 {\displaystyle r_{2}} with tangential velocity V w 2 {\displaystyle V_{w2}} . A velocity triangle paves

3264-409: The fatigue resistance, strength, and creep resistance. Turbine types include condensing, non-condensing, reheat, extracting and induction. Condensing turbines are most commonly found in electrical power plants. These turbines receive steam from a boiler and exhaust it to a condenser . The exhausted steam is at a pressure well below atmospheric, and is in a partially condensed state, typically of

3360-561: The 1860s to the opening of the Wellcome Wing in 2000. The remaining eight chapters cover a variety of themes concerning the museum's development. The Science Museum consists of two buildings – the main building and the Wellcome Wing. Visitors enter the main building from Exhibition Road, while the Wellcome Wing is accessed by walking through the Energy Hall, Exploring Space and then the Making

3456-654: The 1st century by Hero of Alexandria in Roman Egypt . In 1551, Taqi al-Din in Ottoman Egypt described a steam turbine with the practical application of rotating a spit . Steam turbines were also described by the Italian Giovanni Branca (1629) and John Wilkins in England (1648). The devices described by Taqi al-Din and Wilkins are today known as steam jacks . In 1672, an impulse turbine -driven small toy car

3552-569: The Centre Block was completed in 1961–3, the infill of the East Block and the construction of the Lower & Upper Wellcome Galleries in 1980, and the construction of the Wellcome Wing in 2000 result in the museum now extending to Queen's Gate . The leading academic publisher, Palgrave Macmillan, published the official centenary history of the Science Museum on 14 April 2010. The first complete history of

3648-613: The Modern World galleries (see below) at ground floor level. The Energy Hall is the first area that most visitors see as they enter the building. On the ground floor, the gallery contains a variety of steam engines , including the oldest surviving James Watt beam engine , which together tell the story of the British Industrial Revolution . Also on display is a recreation of James Watt's garret workshop from his home, Heathfield Hall , using over 8,300 objects removed from

3744-616: The River Tyne to the sea. The company decided to slow down the deterioration of Turbinia by lifting her out of the water in 1908, and in 1926, the directors of the Parsons Marine Steam Turbine Company offered the ship to the Science Museum, London . Turbinia was sectioned in to two halves, the rear complete with engines and propellers, was put on display in the South Kensington museum in London, which did not have

3840-574: The Science Museum since 1957, Science for the Nation: Perspectives on the History of the Science Museum is a series of individual views by Science Museum staff and external academic historians of different aspects of the Science Museum's history. While it is not a chronological history in the conventional sense, the first five chapters cover the history of the museum from the Brompton Boilers in

3936-488: The United States in 2022 was by the use of steam turbines. Technical challenges include rotor imbalance , vibration , bearing wear , and uneven expansion (various forms of thermal shock ). In large installations, even the sturdiest turbine will shake itself apart if operated out of trim. The first device that may be classified as a reaction steam turbine was little more than a toy, the classic Aeolipile , described in

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4032-552: The Worshipful Company of Clockmakers in London's Guildhall . The Science City 1550–1800: The Linbury Gallery shows how London grew to be a global hub for trade, commerce and scientific enquiry. The Mathematics: The Winton Gallery examines the role that mathematicians have had in building our modern world. In the landing area to access the gallery (stair C) is a working example of Charles Babbage 's Difference engine No.2. This

4128-1370: The blade speed to the absolute steam velocity at the inlet is termed the blade speed ratio ρ = U V 1 {\displaystyle \rho ={\frac {U}{V_{1}}}} . η b {\displaystyle \eta _{b}} is maximum when d η b d ρ = 0 {\displaystyle {\frac {d\eta _{b}}{d\rho }}=0} or, d d ρ ( 2 cos ⁡ α 1 − ρ 2 ( 1 + k c ) ) = 0 {\displaystyle {\frac {d}{d\rho }}\left(2{\cos \alpha _{1}-\rho ^{2}}(1+kc)\right)=0} . That implies ρ = 1 2 cos ⁡ α 1 {\displaystyle \rho ={\frac {1}{2}}\cos \alpha _{1}} and therefore U V 1 = 1 2 cos ⁡ α 1 {\displaystyle {\frac {U}{V_{1}}}={\frac {1}{2}}\cos \alpha _{1}} . Now ρ o p t = U V 1 = 1 2 cos ⁡ α 1 {\displaystyle \rho _{opt}={\frac {U}{V_{1}}}={\frac {1}{2}}\cos \alpha _{1}} (for

4224-410: The bucket-like shaped rotor blades, as the steam jet changes direction. A pressure drop occurs across only the stationary blades, with a net increase in steam velocity across the stage. As the steam flows through the nozzle its pressure falls from inlet pressure to the exit pressure (atmospheric pressure or, more usually, the condenser vacuum). Due to this high ratio of expansion of steam, the steam leaves

4320-581: The command module from the Apollo 10 mission, which are displayed along a timeline chronicling man's technological achievements. A V-2 rocket , designed by German rocket scientist Wernher von Braun , is displayed in this gallery. Doug Millard, space historian and curator of space technology at the museum, states: "We got to the Moon using V-2 technology but this was technology that was developed with massive resources, including some particularly grim ones. The V-2 programme

4416-629: The cosines of the blade angles at the outlet and inlet can be taken and denoted c = cos ⁡ β 2 cos ⁡ β 1 {\displaystyle c={\frac {\cos \beta _{2}}{\cos \beta _{1}}}} . The ratio of steam velocities relative to the rotor speed at the outlet to the inlet of the blade is defined by the friction coefficient k = V r 2 V r 1 {\displaystyle k={\frac {V_{r2}}{V_{r1}}}} . k < 1 {\displaystyle k<1} and depicts

4512-414: The development of flight in the 20th century. Contained in the gallery are several full sized aeroplanes and helicopters , including Alcock and Brown 's transatlantic Vickers Vimy (1919), Spitfire and Hurricane fighters, as well as numerous aero-engines and a cross-section of a Boeing 747 . It opened in 1963 and was refurbished in the 1990s. Power Up is an interactive gaming gallery showcasing

4608-502: The erosion of the blades in last rows. In most of the cases, maximum number of reheats employed in a cycle is 2 as the cost of super-heating the steam negates the increase in the work output from turbine. Extracting type turbines are common in all applications. In an extracting type turbine, steam is released from various stages of the turbine, and used for industrial process needs or sent to boiler feedwater heaters to improve overall cycle efficiency. Extraction flows may be controlled with

4704-1038: The exit of the nozzle is h 2 {\displaystyle h_{2}} . Δ V w = V w 1 − ( − V w 2 ) = V w 1 + V w 2 = V r 1 cos ⁡ β 1 + V r 2 cos ⁡ β 2 = V r 1 cos ⁡ β 1 ( 1 + V r 2 cos ⁡ β 2 V r 1 cos ⁡ β 1 ) {\displaystyle {\begin{aligned}\Delta V_{w}&=V_{w1}-\left(-V_{w2}\right)\\&=V_{w1}+V_{w2}\\&=V_{r1}\cos \beta _{1}+V_{r2}\cos \beta _{2}\\&=V_{r1}\cos \beta _{1}\left(1+{\frac {V_{r2}\cos \beta _{2}}{V_{r1}\cos \beta _{1}}}\right)\end{aligned}}} The ratio of

4800-454: The following companies: Steam turbines are made in a variety of sizes ranging from small <0.75 kW (<1 hp) units (rare) used as mechanical drives for pumps, compressors and other shaft driven equipment, to 1,500 MW (2,000,000 hp) turbines used to generate electricity. There are several classifications for modern steam turbines. Turbine blades are of two basic types, blades and nozzles . Blades move entirely due to

4896-699: The foundation stone for the new building for the Art Museum, she stipulated that the museum be renamed after herself and her late husband . This was initially applied to the whole museum, but when that new building finally opened ten years later, the title was confined to the Art Collections and the Science Collections had to be divorced from it. On 26 June 1909 the Science Museum, as an independent entity, came into existence. The Science Museum's present quarters, designed by Sir Richard Allison , were opened to

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4992-417: The friction due to the blade surface is neglected then η b max = cos 2 ⁡ α 1 {\displaystyle {\eta _{b}}_{\text{max}}=\cos ^{2}\alpha _{1}} . In the reaction turbine , the rotor blades themselves are arranged to form convergent nozzles . This type of turbine makes use of the reaction force produced as

5088-409: The generating capacity of a unit was scaled up by about 10,000 times, and the total output from turbo-generators constructed by his firm C. A. Parsons and Company and by their licensees, for land purposes alone, had exceeded thirty million horse-power. Other variations of turbines have been developed that work effectively with steam. The de Laval turbine (invented by Gustaf de Laval ) accelerated

5184-510: The goodwill or reputation" of Shell. The museum signed a sponsorship contract with the Norwegian oil and gas company Equinor which contained a gagging clause, stating the museum would not say anything that could damage the fossil fuel company's reputation. The museum's director, Ian Blatchford , defended the museum's sponsorship policy, saying: "Even if the Science Museum were lavishly publicly funded I would still want to have sponsorship from

5280-539: The history of video games and consoles from the past 50 years. Visitors can play on over 150 consoles, featuring consoles from the Binatone TV Master to the Play Station 5 . The Tomorrow's World gallery hosts topical science stories and free exhibitions including: The IMAX: The Ronson Theatre is an IMAX cinema which shows educational films (most in 3-D), as well as blockbusters and live events. It features

5376-606: The impact of climate change. The museum has some dedicated spaces for temporary exhibitions (both free and paid-for) and displays, on Level -1 (Basement Gallery), Level 0 (inside the Exploring Space Gallery and Tomorrow's World), Level 1 (Special Exhibition Gallery 1) and Level 2 (Special Exhibition Gallery 2 and The Studio). Most of these travel to other Science Museum Group sites, as well as nationally and internationally. Past exhibitions have included: The Science Museum organises Astronights , "all-night extravaganza with

5472-419: The impact of steam on them and their profiles do not converge. This results in a steam velocity drop and essentially no pressure drop as steam moves through the blades. A turbine composed of blades alternating with fixed nozzles is called an impulse turbine , Curtis turbine , Rateau turbine , or Brown-Curtis turbine . Nozzles appear similar to blades, but their profiles converge near the exit. This results in

5568-591: The introduction of turbines, the Admiralty had been convinced. In 1900, Turbinia steamed to Paris and was shown to French officials, and then displayed at the Paris Exhibition. The first turbine-powered merchant vessel, the Clyde steamer TS  King Edward , followed in 1901. The Admiralty confirmed in 1905 that all future Royal Navy vessels were to be turbine-powered, and in 1906, the first turbine-powered battleship,

5664-409: The kinetic energy supplied to the moving blades (m). Or, E {\displaystyle E} = enthalpy drop over the fixed blades, Δ h f {\displaystyle \Delta h_{f}} + enthalpy drop over the moving blades, Δ h m {\displaystyle \Delta h_{m}} . The effect of expansion of steam over the moving blades

5760-586: The largest axial steam turbines was still below 12% and Turbinia was even less efficient. Despite this, it was a dramatic improvement over predecessors. Parsons' ship turned up unannounced at the Navy Review for the Diamond Jubilee of Queen Victoria at Spithead , on 26 June 1897, in front of the Prince of Wales , foreign dignitaries, and Lords of the Admiralty . As an audacious publicity stunt, Turbinia , which

5856-663: The library was divided over two sites. Histories of science and biographies of scientists were kept at the Imperial College Library until February 2014 when the arrangement was terminated, the shelves were cleared and the books and journals shipped out, joining the rest of the collection, which includes original scientific works and archives at the National Collections Centre. Dana Research Centre and Library previously an event space and cafe, reopened in its current form in 2015. Open to researchers and members of

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5952-642: The loss in the relative velocity due to friction as the steam flows around the blades ( k = 1 {\displaystyle k=1} for smooth blades). η b = 2 U Δ V w V 1 2 = 2 U V 1 ( cos ⁡ α 1 − U V 1 ) ( 1 + k c ) {\displaystyle \eta _{b}={\frac {2U\Delta V_{w}}{{V_{1}}^{2}}}={\frac {2U}{V_{1}}}\left(\cos \alpha _{1}-{\frac {U}{V_{1}}}\right)(1+kc)} The ratio of

6048-463: The middle) before exiting at low pressure, almost certainly to a condenser . The condenser provides a vacuum that maximizes the energy extracted from the steam, and condenses the steam into feedwater to be returned to the boilers. On the left are several additional reaction stages (on two large rotors) that rotate the turbine in reverse for astern operation, with steam admitted by a separate throttle. Since ships are rarely operated in reverse, efficiency

6144-643: The most famous exhibits of what is now the Science Museum. In 1883, the contents of the Patent Office Museum were transferred to the South Kensington Museum. In 1885, the Science Collections were renamed the Science Museum and in 1893 a separate director was appointed. The Art Collections were renamed the Art Museum , which eventually became the Victoria and Albert Museum. When Queen Victoria laid

6240-600: The museum organises an adults only evening with up to 30 events, from lectures to silent discos. Previous Lates have seen conversations with the actress activist Lily Cole and Biorevolutions with the Francis Crick Institute which attracted around 7000 people, mostly under the age of 35. In October 2007, the Science Museum cancelled a talk by the co-discoverer of the structure of DNA, James D. Watson , because he claimed that IQ test results showed black people to have lower intelligence than white people. The decision

6336-519: The museum promising to boycott it following sponsorship of the museum's Energy Revolution exhibition by the coal mining company Adani . The directors of the South Kensington Museum were: The directors of the Science Museum have been: The following have been head/director of the Science Museum in London, not including its satellite museums: The following have been directors of the National Museum of Science and Industry , (since April 2012 renamed

6432-417: The museum with a 12 ft (3.7 m) pink dodo. In 2021, Chris Rapley, a climate scientist, resigned from the museum's advisory board because of oil and gas company sponsorship. In 2021, more than 40 senior academics and scientists said they would not work with the Science Museum due to its financial relationships with the fossil fuel industry. In 2022, more than 400 teachers signed an open letter to

6528-404: The nozzle with a very high velocity. The steam leaving the moving blades has a large portion of the maximum velocity of the steam when leaving the nozzle. The loss of energy due to this higher exit velocity is commonly called the carry over velocity or leaving loss. The law of moment of momentum states that the sum of the moments of external forces acting on a fluid which is temporarily occupying

6624-463: The objects on display come from the Wellcome Collection started by Henry Wellcome . One of the commissioned artworks is a large bronze sculpture of Rick Genest titled Self-Conscious Gene by Marc Quinn . The galleries occupy the museum's entire first floor and opened on 16 November 2019. The Clockmakers Museum is the world's oldest clock and watch museum which was originally assembled by

6720-527: The oil companies." Scientists for Global Responsibility called the museum's move "staggeringly out-of-step and irresponsible". Some presenters, including George Monbiot , pulled out of climate talks on finding they were sponsored by BP and the Norwegian oil company Equinor . Bob Ward of the Grantham Research Institute on Climate Change and the Environment said the "carbon capture exhibition

6816-431: The public in stages over the period 1919–28. This building was known as the East Block, construction of which began in 1913 and was temporarily halted by World War I . As the name suggests it was intended to be the first building of a much larger project, which was never realized. However, the museum buildings were expanded over the following years; a pioneering Children's Gallery with interactive exhibits opened in 1931,

6912-440: The public, it allows free access to almost 7,000 volumes, which can be consulted on site. The Science Museum has been sponsored by major organisations including Shell , BP , Samsung and GlaxoSmithKline . Some have been controversial. The museum declined to give details of how much it receives from oil and gas sponsors. Equinor is also the title sponsor of "Wonderlab: The Equinor Gallery", an exhibition for children, while BP

7008-444: The ratio of the work done on the blades to kinetic energy supplied to the fluid, and is given by A stage of an impulse turbine consists of a nozzle set and a moving wheel. The stage efficiency defines a relationship between enthalpy drop in the nozzle and work done in the stage. η s t a g e = W o r k   d o n e   o n   b l

7104-476: The revolutionary HMS  Dreadnought , was launched. On 11 January 1907, Turbinia was struck and nearly cut in two by Crosby – a ship being launched across-river from the south bank of the Tyne. She was repaired and steamed alongside RMS  Mauretania (also a turbine-powered vessel) after the launch of the great ocean liner. However, mechanical problems prevented Turbinia from accompanying Mauretania down

7200-500: The room, which was sealed after his 1819 death, when the hall was demolished in 1927. Exploring Space is a historical gallery, filled with rockets and exhibits that tell the story of human space exploration and the benefits that space exploration has brought us (particularly in the world of telecommunications). Making the Modern World displays some of the museum's most remarkable objects, including Puffing Billy (the oldest surviving steam locomotive), Crick's double helix , and

7296-468: The space to accommodate the full ship. The fore section was presented in 1944 to Newcastle Corporation, and placed on display in the city's Exhibition Park . In 1959, the Science Museum removed the aft section of Turbinia from display, and by 1961, using a reconstructed centre section, Turbinia was reassembled and displayed in the Newcastle Municipal Museum of Science and Industry. In 1983,

7392-400: The stator and decelerating through the rotor, with no net change in steam velocity across the stage but with a decrease in both pressure and temperature, reflecting the work performed in the driving of the rotor. Energy input to the blades in a stage: E = Δ h {\displaystyle E=\Delta h} is equal to the kinetic energy supplied to the fixed blades (f) +

7488-399: The steam accelerates through the nozzles formed by the stator. Steam is directed onto the rotor by the fixed vanes of the stator . It leaves the stator as a jet that fills the entire circumference of the rotor. The steam then changes direction and increases its speed relative to the speed of the blades. A pressure drop occurs across both the stator and the rotor, with steam accelerating through

7584-444: The steam enters in the middle of the shaft and exits at both ends, or a combination of any of these. In a double flow rotor, the blades in each half face opposite ways, so that the axial forces negate each other but the tangential forces act together. This design of rotor is also called two-flow , double-axial-flow , or double-exhaust . This arrangement is common in low-pressure casings of a compound turbine. An ideal steam turbine

7680-400: The steam to full speed before running it against a turbine blade. De Laval's impulse turbine is simpler and less expensive and does not need to be pressure-proof. It can operate with any pressure of steam, but is considerably less efficient. Auguste Rateau developed a pressure compounded impulse turbine using the de Laval principle as early as 1896, obtained a US patent in 1903, and applied

7776-574: The thermal damage and to limit oxidation . These coatings are often stabilized zirconium dioxide -based ceramics. Using a thermal protective coating limits the temperature exposure of the nickel superalloy. This reduces the creep mechanisms experienced in the blade. Oxidation coatings limit efficiency losses caused by a buildup on the outside of the blades, which is especially important in the high-temperature environment. The nickel-based blades are alloyed with aluminum and titanium to improve strength and creep resistance. The microstructure of these alloys

7872-466: The turbine rotor and the casing. This is illustrated in the drawing of the German 1905 AEG marine steam turbine. The steam from the boilers enters from the right at high pressure through a throttle , controlled manually by an operator (in this case a sailor known as the throttleman). It passes through five Curtis wheels and numerous reaction stages (the small blades at the edges of the two large rotors in

7968-722: The turbine to a French torpedo boat in 1904. He taught at the École des mines de Saint-Étienne for a decade until 1897, and later founded a successful company that was incorporated into the Alstom firm after his death. One of the founders of the modern theory of steam and gas turbines was Aurel Stodola , a Slovak physicist and engineer and professor at the Swiss Polytechnical Institute (now ETH ) in Zurich. His work Die Dampfturbinen und ihre Aussichten als Wärmekraftmaschinen (English: The Steam Turbine and its prospective use as

8064-457: The use of multiple stages in the expansion of the steam, which results in a closer approach to the ideal reversible expansion process. Because the turbine generates rotary motion , it can be coupled to a generator to harness its motion into electricity. Such turbogenerators are the core of thermal power stations which can be fueled by fossil fuels , nuclear fuels , geothermal , or solar energy . About 42% of all electricity generation in

8160-698: The vessel within the River Tyne and the adjacent North Sea; the pictures captured remain the defining image of Turbinia at speed. From this clear demonstration of her speed and power and after further high speed trials attended by the Admiralty, Parsons set up the Turbinia Works at Wallsend, which then constructed the engines for two prototype turbine-powered destroyers for the Navy, HMS  Viper and HMS  Cobra , that were launched in 1899. Both vessels were lost to accidents in 1901, but although their losses slowed

8256-731: The way for a better understanding of the relationship between the various velocities. In the adjacent figure we have: Then by the law of moment of momentum, the torque on the fluid is given by: For an impulse steam turbine: r 2 = r 1 = r {\displaystyle r_{2}=r_{1}=r} . Therefore, the tangential force on the blades is F u = m ˙ ( V w 1 − V w 2 ) {\displaystyle F_{u}={\dot {m}}\left(V_{w1}-V_{w2}\right)} . The work done per unit time or power developed: W = T ω {\displaystyle W=T\omega } . When ω

8352-456: Was built by the Science Museum and its main part completed in 1991, to celebrate 200 years since Babbage's birth, and was designed by Zaha Hadid Architects . The Information Age gallery has exhibits covering the development of communications and computing over the last two centuries. It explores the six networks that have transformed global communications: The Cable, The Telephone Exchange, Broadcast, The Constellation, The Cell and The Web It

8448-547: Was criticised by some scientists, including Richard Dawkins , but supported by other scientists, including Steven Rose . The museum has undergone many changes in its history with older galleries being replaced by new ones. Blythe House, 1979–2019, the museum's former storage facility in West Kensington , while not a gallery, it offered tours of the collections housed there. Objects formerly housed there are being transferred to

8544-466: Was designed by Ferdinand Verbiest . A more modern version of this car was produced some time in the late 18th century by an unknown German mechanic. In 1775 at Soho James Watt designed a reaction turbine that was put to work there. In 1807, Polikarp Zalesov designed and constructed an impulse turbine, using it for the fire pump operation. In 1827 the Frenchmen Real and Pichon patented and constructed

8640-466: Was founded in 1857 and is one of the city's major tourist attractions, attracting 3.3 million visitors annually in 2019. Like other publicly funded national museums in the United Kingdom, the Science Museum does not charge visitors for admission, although visitors are requested to make a donation if they are able. Temporary exhibitions may incur an admission fee. It is one of the five museums in

8736-703: Was hugely expensive in terms of lives, with the Nazis using slave labour to manufacture these rockets". Stephenson's Rocket used to be displayed in this gallery. After a short UK tour, since 2019 Rocket is on permanent display at the National Railway Museum in York, in the Art Gallery. The Medicine: The Wellcome Galleries is a five-gallery medical exhibition which spans ancient history to modern times with over 3000 exhibits and specially commissioned artworks. Many of

8832-403: Was kept informed of developments, and Turbinia was launched on 2 August 1894. Despite the success of the turbine engine, initial trials with one propeller were disappointing. After discovering the problem of cavitation and constructing the first cavitation tunnel , Parsons' research led to his fitting three axial-flow turbines to three shafts, each shaft in turn driving three propellers, giving

8928-472: Was licensed and the turbine scaled up shortly after by an American, George Westinghouse . The Parsons turbine also turned out to be easy to scale up. Parsons had the satisfaction of seeing his invention adopted for all major world power stations, and the size of generators had increased from his first 7.5 kilowatts (10.1 hp) set up to units of 50,000 kilowatts (67,000 hp) capacity. Within Parsons' lifetime,

9024-454: Was much faster than any other ship at the time, raced between the two lines of navy ships and steamed up and down in front of the crowd and princes, while easily evading a navy picket boat that tried to pursue her, almost swamping it with her wake. Photographer and cinematographer Alfred J. West took several photographs of Turbinia travelling at full speed at the review. He was subsequently invited by Sir Charles Parsons to film and photograph

9120-462: Was opened on 24 October 2014 by the Queen, Elizabeth II , who sent her first tweet from here. One of the most popular galleries in the museum is the interactive Wonderlab:The Equinor Gallery , formerly called Launchpad . The gallery is staffed by Explainers who demonstrate how exhibits work, conduct live experiments and perform shows to schools and the visiting public. The Flight gallery charts

9216-415: Was the first area to be refurbished, with the main part of the work involving raising the roof by one storey to create viewing galleries on three levels. 54°58′8.9″N 1°37′28.2″W  /  54.969139°N 1.624500°W  / 54.969139; -1.624500 Steam turbine The steam turbine is a form of heat engine that derives much of its improvement in thermodynamic efficiency from

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