Talk:Troy and Gas turbine: Difference between pages

Revision as of 06:54, 20 July 2005

Revision as of 17:47, 31 October 2005

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[[Image:GasTurbine.jpg|thumb|right|400px|This machine has a single-stage radial [[compressor]] and turbine, a [[recuperator]], and [[foil bearings]]. ]]

Does anyone want to have a go at writing up some of the current theories summarised in a recent edition of the [[BBC]]'s ''Horizon'' programme? A transcript is available online here [http://www.bbc.co.uk/science/horizon/2004/troytrans.shtml]

A '''gas turbine''' is a rotary [[engine]] that extracts energy from a flow of [[combustion]] gas. It has an upstream [[compressor]] coupled to a downstream [[turbine]], and a combustion chamber in-between. ('''Gas turbine''' may also refer to just the [[turbine]] element.)

Another page in their site even links to this very article! [[User:Timrollpickering|Timrollpickering]] 23:13, 15 Apr 2004 (UTC)

[[Energy]] is added to the gas stream in the [[combustor]], where [[air]] is mixed with [[fuel]] and [[ignition system|ignited]]. Combustion increases the [[temperature]], [[velocity]] and [[volume]] of the gas flow. This is directed through a diffuser ([[nozzle]]) over the turbine's blades, spinning the turbine and powering the compressor.

Energy is extracted in the form of shaft power, compressed air and thrust, in any combination, and used to power [[aircraft]], [[train]]s, [[ship]]s,[[generator]]s, and even [[tank]]s.

==alleged/suspected/hypothesized/proposed Troy==

In the light of the findings since 1996, this article is far too cautious about identifying archaeological with homeric Troy. Of course the "identity" is not complete, not proven beyond a shadow of a doubt, and the controversy should be noted. Since 1996, however, a strong majority of scholars identify ''(W)ilion'' and ''Wilusha'', and for very good reasons. I will try to add sections concerning these recent developments. [[User:Dbachmann|dab]] 18:42, 5 Oct 2004 (UTC)

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==Opening doesn't make much sense==

The opening of the article, "Troy (...) is not a legendary city, scene of the Trojan war" doesn't make much sense. Is that supposed to say "is a legendary city"? ~~

:fixed it (it was vandalism. you can fix these things yourself, too) [[User:Dbachmann|dab]] <small>[[User_talk:Dbachmann|('''&#5839;'''</small>)]] 12:57, 16 Jan 2005 (UTC)

== The Real LocationTheory of Troy operation==

Gas turbines are described [[thermodynamics|thermodynamically]] by the [[Brayton cycle]], in which air is compressed [[isentropic]]ally, [[combustion]] occurs at constant pressure, and expansion over the turbine occurs isentropically back to the starting pressure.

In practise, friction and turbulence cause:

There is a very intersting theory that has its roots in geography and archeology, and puts Troy much closer to Greece... Check it out at: http://www.troya.com.mx/. The book was published in Croatian, and it is by no means a work of an amateur, R. Salinas Price is a scholar educated in the United States, more on his study on Homer at: http://www.homer.com.mx/index.html

a) non-isentropic compression - for a given overall pressure ratio, the compressor delivery temperature is higher than ideal

:Yugoslav Troy? Well, feel free to add it as an intriguing 'dissenting voice.' No "the real ___location"-style statements in the article, though, please. [[User:Dbachmann|dab]] <small>[[User_talk:Dbachmann|('''&#5839;'''</small>)]] 09:08, 19 Jan 2005 (UTC)

b) non-isentropic expansion - although the turbine temperature drop necessary to drive the compressor is unaffected, the associated pressure ratio is greater, which decreases the expansion available to provide useful work.

Feel free to not mention that garbage at all in the article, also. [[User:Decius|Decius]] 07:43, 6 Mar 2005 (UTC)

a) a pressure loss in the combustor - reduces the expansion available to provide useful work.

Patton 117 reporting in, p[lease feel free to see the discussion below about how it was in England. go to the link before you bash it please.

[[Image:Brayton cycle.png]]

== Wrong Category ==

As with all cyclic [[heat engine]]s, higher combustion temperature means greater [[efficiency]]. The limiting factor is the ability of the steel, ceramic, or other materials that make up the engine to withstand heat and pressure. Considerable engineering goes into keeping the turbine parts cool. Most turbines also try to recover exhaust heat, which otherwise is wasted energy. [[Recuperator]]s are [[heat exchanger]]s that pass exhaust heat to the compressed air, prior to combustion. [[Combined cycle]] designs pass waste heat to [[steam turbine]] systems. And [[combined heat and power]] (co-generation) uses waste heat for hot water production.

Mechanically, gas turbines can be considerably less complex than [[internal combustion]] piston engines. Simple turbines might have one moving part: the shaft/compressor/turbine/alternator-rotor assembly (see image above), not counting the fuel system.

Ancient [[Troy]] was not in any way an ancient "Greek" city, so I've rearranged the category. [[User:Decius|Decius]] 05:59, 6 Mar 2005 (UTC)

:well, everybody speaks Greek in Homer. Plus, there is some evidence that there may have been a Greek upper-class that had imposed itself on the Luwian population, in Wilusa. But it's difficult to classify anything as "Greek" in that time anyway, there were only "Achaean" and "Danaans" etc. [[User:Dbachmann|dab]] <small>[[User_talk:Dbachmann|('''&#5839;'''</small>)]] 10:07, 6 Mar 2005 (UTC)

More sophisticated turbines may have multiple shafts (spools), hundreds of turbine blades, movable stator blades, and a vast system of complex piping, combustors and heat exchangers.

Patton 117 here, Homer's story was about a celtic civil war, and was translated into greek so that the people he was telling the story to the greeks

As a general rule, the smaller the engine the faster the shaft/s rotate, to maintain tip speed: [[Jet engine]]s operate around 10,000 rpm and micro turbines around 100,000 rpm.

== Troy in England ==

Well it was written by the greeks from Homer's original versiopn which was translated from his native celtic tounge to greek

[[Thrust bearing]]s and [[plain bearing|journal bearings]] are a critical part of design. Traditionally, they have been [[Fluid_bearing|hydrodynamic oil bearings]], or oil-cooled [[Ball_bearing|ball bearings]]. This is giving way to hydrodynamic [[foil bearing]]s, which have become common place in micro turbines and APU&#8217;s (auxiliary power units.)

== Troy in England ==

==[[Jet engine]]s==

Has anyone ever read Iman Wilkins book where troy once stood, in it he describes why Troy would have been a Celtic City, and how the Aecheans, which means seamen, where warriors from central europe who banded together to capture the british celts tin mines so that the mainland europena Celts could make bronze at a cheaper price. the following link will lead you to the site

See [[jet engine]] page.

http://www.troy-in-england.co.uk/

:a typical case of [[pseudohistory]]. [[User:Dbachmann|dab]] <small>[[User_talk:Dbachmann|('''&#5839;''')]]</small> 16:37, 18 July 2005 (UTC)

== Gas turbines for electrical power production ==

If you read it, the invaders are described as travelling over a wine dark sea called Oceanus. The Greeks would have called it the Ægean sea, which is a deep blue color as compared to the Northern Atlantic which is often described as being wine dark

[[Image:GE_H_series_Gas_Turbine.jpg|thumb|left|350px| GE H series power generation gas turbine. This 400-[[megawatt]] unit has a rated [[Thermodynamic_efficiency|thermal efficiency]] of 60% in [[combined cycle]] configurations.]]

Industrial gas turbines range in size from truck-mounted mobile plants to enormous, complex systems.

Also, Achilles is noted as watching the sun rise over the sea and his barracks. Which means that an Asian landing site is out of the question which would put the shores on the west.

The power turbines in the largest industrial gas turbines operate at 3,000 or 3,600 [[rpm]] to match the [[alternating current|AC]] [[power grid]] frequency and to avoid the need for a reduction gearbox. Such engines require a dedicated building.

Achean is also a greek version of a CELTIC word that means Water Men

There are seven rivers flowing across the Troad. there is also an eighth river called the Temese, which was the name for the Thames untill the 850's AD. the turkish plain has two rivers.

They can be particularly efficient&mdash;up to 60 percent&mdash;when waste heat from the gas turbine is recovered by a conventional steam turbine in a [[combined cycle]] configuration.

I would like to take the claim for creating this discussion, as i was not supposed to be working on this at the time due to the fact that i am taking a computer Apps class at this time. Patton 117

Simple cycle gas turbines in the power industry require smaller capital investment than combined cycle gas, [[coal]] or [[nuclear]] plants and can be designed to generate small or large amounts of power. Also, the actual construction process can take as little as several weeks to a few months, compared to years for baseload plants. Their other main advantage is the ability to be turned on and off within minutes, supplying power during peak demand. Large simple cycle gas turbines may produce several hundred megawatts of power and approach 40 percent [[Thermodynamic_efficiency|thermal efficiency]].

:again, this is so far out on the lunatic fringe that it's not worth refuting. At most, if you must, insert a single sentence saying somebody came up with the idea. For anything more, create a subarticle dedicated to the theory. [[User:Dbachmann|dab]] <small>[[User_talk:Dbachmann|('''&#5839;''')]]</small> 07:19, 19 July 2005 (UTC)

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==Micro turbines==

You remind me of the lunatic conservaties who say that Harry Potter is evil, and have never even read it. I, Patton 117, am a conservative who reads the books by the way.

[[Image:Micro turbine.jpg|thumb|right|200px|A micro turbine designed for [[DARPA]] by M-Dot]]

Also known as:

:I have read it, and it's not remotely believable. [[User:Jamesmusik|James]] 23:15, July 19, 2005 (UTC)

*Turbo alternators

*Gensets

*MicroTurbine® (registered trademark of [[Capstone Turbine Corporation]])

*Turbogenerator® (registered tradename of [[Honeywell Power Systems]], Inc.)

'''Micro turbines''' are becoming wide spread for [[Distributed generation|distributed power]] and [[cogeneration|combined heat and power]] applications. They range from handheld units producing less than a [[kilowatt]] to commercial sized systems that produce tens or hundreds of kilowatts.

Why not, i have read both the Iliad and Iman Wilkins book, and find it meshes

Part of their success is due to advances in electronics, which allow unattended operation and interfacing with the commercial power grid. Electronic power switching technology eliminates the need for the generator to be synchronized with the power grid. This allows, for example, the generator to be integrated with the turbine shaft, and to double as the starter motor.

:Mainly because it's based on questionable etymologies. [[User:Jamesmusik|James]] 04:31, July 20, 2005 (UTC)

Micro turbine systems have many advantages over piston engine generators, such as higher power density (with respect to footprint and weight), extremely low emissions and few, or just one, moving part. Those designed with [[foil bearings]] and air-cooling operate without oil, coolants or other hazardous materials. However, piston engine generators are quicker to respond to changes in output power requirement.

So how do you explain the fact that Achiles was able to watch the sun rise over both the ocean and the soldiers barracks. Also, I forgot to mention this, but greeks for centuries back have been of average height, average, complexion, with brown hair and brown eyes. Agamemnon is blond, as is Achiles. Traits that resemble the Celts more than the Greeks.

They accept most commercial fuels, such as [[natural gas]], [[propane]], [[diesel]] and [[kerosene]]. The are also able to produce [[renewable energy]] when fueled with [[biogas]] from [[landfills]] and [[sewage treatment]] plants.

:The Iliad is an oral poem, and as such inconsitencies and errors crept in over the several hundred years during which it was composed. Also, the person who "wrote" it was likely not there, so they would have no real idea on which side of Troy the camp was. Also, there's no concrete proof about what Greeks looked like over the centuries. Furthermore, there's nothing to suggest that blonde in the Iliad is the same thing as blonde today. [[User:Jamesmusik|James]] 05:09, July 20, 2005 (UTC)

Micro turbine designs usually consist of a single stage radial compressor, a single stage [[radial turbine]] and a recuperator. Recuperators are difficult to design and manufacture because they operate under high pressure and temperature differentials. Exhaust heat can be used for water heating, drying processes or absorption chillers, which create cold for air conditioning from heat energy instead of electric energy.

what? I'm not saying anything is "evil". I am saying it is stupid. Nobody claims Harry Potter is a factual report. If you claim that this England business is fiction then no problem. The arguments are crap, man. Take a good look at the map of the Troas. See the bay? Is that a north-to-south coast facing west? I thought so. [[User:Dbachmann|dab]] <small>[[User_talk:Dbachmann|('''&#5839;''')]]</small> 06:43, 20 July 2005 (UTC)

Typical micro turbine efficiencies are 25 to 35 percent. When in a combined heat and power [[cogeneration]] system, efficiencies of greater than 80 percent are commonly achieved.

[[:Image:Homeric greece.png]]

Have a look at that map. The poem, in spite of being oral, contains exact knowledge of Greece and Anatolia. Now take a list at [[Trojan_War#Armies_on_the_Trojan_side]]. These are all historical peoples of [[Anatolia]]. What were the [[Phrygian]]s doing in England? The [[Caria]]ns? The [[Lycia]]ns? etc.?? You may as well claim that the Greeks were really Eskimos invading the Aztecs. The theory is too kooky even to waste breath on it, sorry. Read some serious books about Troy. [[User:Dbachmann|dab]] <small>[[User_talk:Dbachmann|('''&#5839;''')]]</small> 06:54, 20 July 2005 (UTC)

==Auxiliary power units==

[[Auxiliary power unit]]s (APUs) are small gas turbines designed for auxiliary power of larger machines, usually [[aircraft]]. They are well suited for supplying compressed air for aircraft ventilation (with an appropriate compressor design), start-up power for larger [[jet engine]]s, and electrical and hydraulic power. (These are not to be confused with the auxiliary propulsion units, also abbreviated APUs, aboard the gas-turbine-powered Oliver Hazard Perry-class guided-missile frigates. The Perrys' APUs are large electric motors that provide maneuvering help in close waters, or emergency backup if the gas turbines are not working.)

==Gas turbines in vehicles==

Gas turbines are used on [[ship]]s, [[locomotive]]s, [[helicopter]]s, and in [[tank]]s. A number of experiments have been conducted with gas turbine powered [[automobile]]s.

In 1950, designer F. R. Bell and Chief Engineer Maurice Wilks from British car manufacturers [[Rover (car)|Rover]] unveiled the first car powered with a gas turbine engine. The two-seater JET1 had the engine positioned behind the seats, air intake grilles on either side of the car and exhaust outlets on the top of the tail. During tests, the car reached top speeds of 140 km/h, at a turbine speed of 50,000 rpm. The car ran on [[petrol]], [[paraffin]] or [[diesel]] oil, but fuel consumption problems proved insurmountable for a production car. It is currently on display at the London [[Science Museum (London)|Science Museum]]. Rover and the BRM [[Formula One]] team joined forces to produce a gas turbine powered coupe, which entered the 1963 [[24 hours of Le Mans]], driven by [[Graham Hill]] and Richie Ginther. It averaged 107.8 mph (173 km) and had a top speed of 142 mph (229 km/h). American car manufacturer [[Chrysler]] demonstrated several prototype gas turbine-powered cars from the early 1950s through the early 1980s. [http://www.aardvark.co.nz/pjet/chrysler.shtml A history of Chrysler turbine cars]. In [[1993]] [[General Motors]] introduced the first commercial gas turbine powered [[hybrid vehicle]]&mdash;as a limited production run of the [[EV-1]]. A [[Williams International]] 40 kW turbine drove an alternator which powered the battery-electric powertrain. The turbine design included a [[recuperator]].

Gas turbines offer a high-powered engine in a very small and light package. However, they are not as responsive and efficient as small piston engines over the wide range of rpms and powers needed in vehicle applications. Also, turbines have historically been more expensive to produce than piston engines, though this is partly because piston engines have been mass-produced in huge quantities for decades, while small turbines are rarities. It is also worth noting that a key advantage of jets and [[turboprop]]s for aeroplane propulsion - their superior performance at high altitude compared to piston engines, particularly [[natural aspiration|naturally-aspirated]] ones - is irrelevant in automobile applications. Their power-to-weight advantage is far less important. Their use in hybrids reduces the second problem. Capstone currently lists on their website a version of their turbines designed for installation in hybrid vehicles.

Production gas turbine motorcycle first appeared in [[MTT Turbine SUPERBIKE]] in 2000. This high-priced machine is produced in miniscule numbers.

Use of gas turbines in military tanks has been more successful. In the 1950s, a [[Conqueror tank | Conqueror heavy tank]] was experimentally fitted with a [[Parsons]] 650-hp gas turbine, and they have been used as [[auxiliary power unit]]s in several other production models. Today, the Soviet/Russian [[T-80]] and U.S. [[M1 Abrams]] tanks use gas turbine engines. See [[Tank#Gas turbines |tank]] for more details.

===Naval use===

Gas turbines are used in many naval vessels, where they are valued for their high power-to-weight ratio and their ships' resulting acceleration and ability to get underway quickly. The first gas-turbine-powered naval vessel was the [[Royal Navy]]'s Motor Gun Boat ''MGB 2009'' (formerly ''MGB 509'') converted in 1947. The first large, gas-turbine powered ships, were the Royal Navy's [[Tribal class frigate|Type 81 (Tribal class)]] [[frigate]]s, the first of which ([[HMS Ashanti (F117)|HMS ''Ashanti'']]) was commissioned in [[1961]].

The first U.S. gas-turbine powered ships were the [[United States Coast Guard|U.S. Coast Guard]]'s [[Hamilton class cutter|''Hamilton''-class]] [[USCG high endurance cutter|High Endurance Cutters]] the first of which ([[USCGC Hamilton (WHEC-715)|USCGC ''Hamilton'']]) commissioned in [[1967]]. Since then, they have powered the [[United States Navy|U.S. Navy]]'s [[Oliver Hazard Perry class frigate|''Perry''-class frigates]], [[Spruance class destroyer|''Spruance''-class]] and [[Arleigh Burke class destroyer|''Arleigh Burke''-class]] [[destroyer]]s, and [[Ticonderoga class cruiser|''Ticonderoga''-class guided missile cruisers]]. [[USS Makin Island (LHD-8)|USS ''Makin Island'']], a modified [[Wasp class amphibious assault ship|''Wasp''-class amphibious assault ship]], is to be the Navy's first [[amphibious assault ship|amphib]] powered by gas turbines.

==Amateur gas turbines==

A popular hobby is to construct a gas turbine from an automotive [[turbocharger]]. A combustion chamber is fabricated and plumbed between the compressor and turbine. Like many technology based hobbies, they tend to give rise to manufacturing businesses over time. Several small companies manufacture small turbines and parts for the amature. See external links for resources.

==Advances in technology==

Gas turbine technology has steadily advanced since its inception and continues to evolve; research is active in producing ever smaller gas turbines. Computer design, specifically [[CFD]] and [[finite element analysis]] along with material advances, has allowed higher compression ratios and temperatures, more efficient combustion, better cooling of engine parts and reduced emissions. Additionally, compliant [[foil bearing]]s were commercially introduced to gas turbines in the [[1990s]]. They can withstand over a hundred thousand start/stop cycles and eliminated the need for an oil system.

On another front, microelectronics and power switching technology have enabled commercially viable micro turbines for distributed and vehicle power. An excellent example is the Capstone line of micro turbines, which do not require an oil system and can run unattended for months on end.

==See also==

*[[turbine]]

*[[jet engine]]

*[[Brayton cycle]]

==Further reading==

* ''Gas Turbine Engines for Model Aircraft'' by [[Kurt Schreckling]], ISBN 0 9510589 1 6 Traplet Publications

==External links==

* [http://web.mit.edu/aeroastro/www/labs/GTL/gtl_about.html MIT Gas Turbine Laboratory]

* [http://www.memagazine.org/backissues/october97/features/turbdime/turbdime.html MIT Microturbine research]

* [http://www.sciencemuseum.org.uk/collections/treasures/margas.asp First Marine Gas Turbine 1947]

'''Amature groups and small manufacturers'''

* [http://groups.yahoo.com/group/DIYGasTurbines DIY Gas Turbines Yahoo Group]

* [http://www.power.alstom.com/home/equipment___systems/turbines/gas_turbines/7323.EN.php?languageId=EN&dir=/home/equipment___systems/turbines/gas_turbines/ ALSTOM Gas Turbines]

* [http://www.nyethermodynamics.com Nye Thermodynamics Corporation]

* [http://www.Innodyn.com Innodyn]

* [http://www.m-dot.com/page8.html M-Dot Microturbines]

'''Large turbine manufacturers'''

* [http://www.rolls-royce.com/energy/products/oilgas/gasturb.jsp Rolls-Royce Gas Turbines]

* [http://www.mpshq.com/products_gasturbines.htm Mitsubishi Gas Turbines]

* [http://www.gepower.com/prod_serv/products/gas_turbines_cc/en/index.htm GE Gas Turbines]

* [http://www.siemenswestinghouse.com/en/gasturbinesitem/index.cfm Siemens Gas Turbines]

* [http://www.microturbine.com/ Capstone Microturbines]

* [http://mysolar.cat.com/cda/layout Solar Turbines]

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