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Talk:1 E9 kg

 * # 3,500,000 tonnes: world oil production in 1999

That should be daily world oil production, shouldn't it? Mkweise 22:14 Feb 22, 2003 (UTC)

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Talk:1 E9 kg


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Open All Hours

Open All Hours is a British television sitcom created and written by Roy Clarke for the BBC. It ran for 26 episodes in four series, which aired in 1976, 1981, 1982 and 1985. The programme was developed from a television pilot broadcast in Ronnie Barker's Seven of One (1973) comedy anthology series. Open All Hours ranked eighth in the 2004 Britain's Best Sitcom poll. A sequel, titled Still Open All Hours, aired from 2013 to 2019.

Premise
The show's setting is a small grocer's shop in Balby, a suburb of Doncaster in South Yorkshire. The owner, Albert Arkwright (Ronnie Barker), is a middle-aged miser with a stammer and a knack for selling. His nephew Granville (David Jason) is his beleaguered put-upon errand boy who blames his work schedule for his lacklustre social life.

Across the road lives nurse Gladys Emmanuel (Lynda Baron), largely occupied by her professional rounds, and her elderly mother. Arkwright longs to marry Gladys, but she resists his persistent pressures. In later episodes it is explained that the two have been engaged for many years but have been unable to wed because of the advanced age of her mother, for whom she cares at home, as well as the mutual loathing between her mother and Arkwright. Though short-tempered with her fiancé, she is concerned for his and Granville's welfare. In order to avoid Gladys's mother, Arkwright frequently attempts to 'visit' Gladys via a ladder to an upstairs window, which often ends in catastrophe.

Episodes
Twenty-six episodes of Open All Hours, all written by Roy Clarke, were produced for the BBC. The show began airing in 1976 with the pilot episode and ended in 1985 after the fourth series. All episodes have a running time of 30 minutes.

Still Open All Hours
A sequel, entitled Still Open All Hours, was created in 2013 by original writer Roy Clarke and featuring several original cast members, including David Jason, Lynda Baron, Stephanie Cole and Maggie Ollerenshaw. On 30 January 2014, the BBC commissioned Still Open All Hours for six new episodes beginning on 26 December 2014 and ran for six series until 2019.

Open All Hours and Still Open All Hours, has run for a total of 67 episodes across ten series.

Arkwright
Albert Arkwright is a pragmatic, miserly man with old-fashioned values, whose world seems to stop at his shop door, except for his uncontrollable lust for Nurse Gladys Emmanuel, which may prompt him on occasion to wander across the road, usually with a ladder, to gain access to her bedroom window. Arkwright is a devious and mildly dishonest character, who has many crafty tricks to try to persuade a customer to leave his shop having bought at least one thing, and will avoid spending his own money at all costs. He is also very protective of his savings, keeping some in his pocket wrapped in a fine gold chain, and some in an old, battered Oxo tin that he hides under the kitchen sink. This includes, or so he claims, coins from before 1922, when they were "solid silver".

Granville
Granville is the son of Arkwright's sister. She died a single mother when Granville was very young, leaving Arkwright to bring up the boy. Arkwright's jokes imply that his sister was promiscuous; he frequently speculates that Granville's father is Hungarian, and was forbidden to marry Granville's mother because she was English. He is often referred to as a "youth" or "young lad", even though Granville is well into his adult years. (In the Pilot episode he states that he is 25 years old.)

Granville is shy and awkward, but kind. His priorities differ from those of his uncle. He always feels that life is passing him by. Occasionally, people from Granville's past come into the shop. To Granville, who is ever saddled with his shop duties and bearing his uncle's belittling, their lives seem richer and more fulfilling.

When Granville has a fling with the milkwoman (played by Barbara Flynn), his uncle is unsupportive.

Series development
The shop is based on a little store called L E Riddiford in Thornbury, Gloucestershire. Roy Clarke visited this small town whilst travelling and was said to have fallen in love with the shop layout and its owner, Len Riddiford.

Ronnie Barker proposed that Arkwright should have a stammer, and this was written into the character. Barker also co-created the premise of the dangerous till. In the series, the shop's antiquated till has a drawer that tends to snap shut suddenly. Even though this terrifies Granville and Arkwright, Arkwright refuses to replace the till due to the cost of a replacement, and because he believes it discourages burglars. In the documentary Open All Hours: A Celebration, Sydney Lotterby revealed that the till was controlled with a string by an assistant floor manager in the adjacent room, and that he once accidentally caught Barker's fingers while filming. By the time of Still Open All Hours, it is suggested that the till is now haunted by Arkwright's ghost as it sporadically opens and closes violently at the mere suggestion of Granville spending money.

Filming locations
The exterior shots were shot on Lister Avenue in Balby, a suburb of Doncaster; South Yorkshire. The shop itself is a hairdresser's salon, which closed for a summer break during each year the series was being filmed by the BBC. The same location is used for the sequel series Still Open All Hours. The pilot episode (featured in the series Seven of One) used a shop front on the western intersection of Drayton Avenue and Manor Road in Ealing, London, for exterior filming.

In the first series, Nurse Gladys lives at 34 Lister Avenue. This is changed to 32 from the second series.

The local council considered demolishing the shop used in Open All Hours. A fan created a web site to garner support for preserving it. The shop was to be auctioned in Leeds on 24 November 2008, and was expected to fetch between £120,000 and £130,000; however, all bids fell short of the reserve price.

Three years earlier, a different sort of auction commemorated the programme. The BBC donated, to the British Stammering Association (BSA), two of the false moustaches worn by Ronnie Barker in the series. The BSA auctioned the moustaches at their London conference in September 2005, shortly before Barker's death.

Theme tune
The show's theme tune is a song called "Alice, Where Art Thou?", written by Joseph Ascher. The arrangement is borrowed from a 1926 Charles Penrose song called Laughter And Lemons, the b side of the more well-known The Laughing Policeman. It was arranged for a brass band and performed by Max Harris, who also wrote the incidental music for the programme.

Reception
Barker noted in his autobiography It's Hello from Him that he received a letter which began "We are a family of stutterers...", that made his heart sink. However, the writer went on to praise his portrayal and added that the whole family found the character hilarious.

Books
Two books related to the programme have been released in the UK. One was written by Graham McCann and published by BBC Books in October 2014 and the other one, a 'novelisation' based on scripts for the first series, was written by Christine Sparks and was published by BBC Books.

This was published in February 1981 which is based on the original programme. This was published on 30 October 2014.
 * Open All Hours
 * Still Open All Hours: The Story of a Classic Comedy

VHS releases
A selection of 15 episodes of the series was released on five VHS cassettes by BBC Video on 2 April 1990, 12 June 1995, 4 March 1996, 2 June 1997, and 2 March 1998. Universal Playback, under licence by BBC Worldwide, released Series 1 and 2 as a three tape boxset on 19 August 2002 and Series 3 and 4 as a three tape set boxset on 2 June 2003.

DVD releases
All four series have been released in Regions 2 and 4, both individually and in box sets. Region 1 has released the box set but the series have not been released individually there. In Australia, the BBC with Roadshow released "Series One: Episodes 1–3 Comedy Bites" in 2010.

Planned spin-off
In 1984, at which time no new episodes of the series had been produced for two years, a spin-off was proposed based around Lynda Baron's character, Nurse Gladys Emmanuel. Given the working title Call the Nurse, this spin-off series would have followed Nurse Gladys as she visited various eccentric and demanding patients. The characters of Arkwright and Granville were not written to appear, and Roy Clarke was keen to develop a new set of supporting characters rather than rely on those already built up for Open All Hours. A thirty-minute pilot was written but did not enter production as the BBC turned down the series; instead, Open All Hours returned for its fourth and what would be its final series the following year.

title: Open All Hours


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London and North Western Railway

The London and North Western Railway (LNWR, L&NWR) was a British railway company between 1846 and 1922. In the late 19th century, the LNWR was the largest joint stock company in the world.

Dubbed the "Premier Line", the LNWR's main line connected four of the largest cities in England; London, Birmingham, Manchester and Liverpool, and, through cooperation with their Scottish partners, the Caledonian Railway also connected Scotland's largest cities of Glasgow and Edinburgh. Today this route is known as the West Coast Main Line. The LNWR's network also extended into Wales and Yorkshire.

In 1923, it became a constituent of the London, Midland and Scottish (LMS) railway, and, in 1948, the London Midland Region of British Railways.

History

The company was formed on 16 July 1846 by the amalgamation of the Grand Junction Railway, London and Birmingham Railway and the Manchester and Birmingham Railway. This move was prompted, in part, by the Great Western Railway's plans for a railway north from Oxford to Birmingham. The company initially had a network of approximately 350 mi, connecting London with Birmingham, Crewe, Chester, Liverpool and Manchester.

The headquarters were at Euston railway station. As traffic increased, it was greatly expanded with the opening in 1849 of the Great Hall, designed by Philip Charles Hardwick in classical style. It was 126 ft long, 61 ft wide and 64 ft high and cost £150,000. The station stood on Drummond Street. Further expansion resulted in two additional platforms in the 1870s with four more in the 1890s, bringing the total to 15.

The LNWR described itself as the Premier Line. This was justified, as it included the pioneering Liverpool and Manchester Railway of 1830 and the original LNWR main line linking London, Birmingham and Lancashire had been the first big railway in Britain, opened throughout in 1838. As the largest joint stock company in the United Kingdom, it collected a greater revenue than any other railway company of its era.

With the Grand Junction Railway acquisition of the North Union Railway in 1846, the London and North Western Railway operated as far north as Preston. In 1859, the Lancaster and Preston Junction Railway amalgamated with the Lancaster and Carlisle Railway and this combined enterprise was leased to the London and North Western Railway, giving it a direct route from London to Carlisle.

In 1858, they merged with the Chester and Holyhead Railway and became responsible for the lucrative Irish Mail trains via the North Wales Main Line to Holyhead.

On 1 February 1859, the company launched the limited mail service, which was only allowed to take three passenger coaches, one each for Glasgow, Edinburgh and Perth. The Postmaster General was always willing to allow a fourth coach, provided the increased weight did not cause time to be lost in running. The train was timed to leave Euston at 20.30 and operated until the institution of a dedicated post train, wholly of Post Office vehicles, in 1885. On 1 October 1873 the first sleeping carriage ran between Euston and Glasgow, attached to the limited mail. It ran three nights a week in each direction. On 1 February 1874 a second carriage was provided and the service ran every night.

In 1860, the company pioneered the use of the water trough designed by John Ramsbottom. It was introduced on a section of level track at Mochdre, between Llandudno Junction and Colwyn Bay. The company inherited several manufacturing facilities from the companies with which it merged, but these were consolidated and in 1862, locomotive construction and maintenance was done at the Crewe Locomotive Works, carriage building was done at Wolverton and wagon building was concentrated at Earlestown.

At the core of the LNWR system was the main line network connecting London Euston with the major cities of Birmingham, Liverpool and Manchester, and (through co-operation with the Caledonian Railway) Edinburgh and Glasgow. This route is today known as the West Coast Main Line. A ferry service also linked Holyhead to Greenore in County Louth, where the LNWR owned the 26 mi Dundalk, Newry and Greenore Railway, which connected to other lines of the Irish mainline network at Dundalk and Newry.

The LNWR also had the Huddersfield Line connecting Liverpool and Manchester with Leeds, and secondary routes extending to Nottingham, Derby, Peterborough and South Wales.

At its peak just before World War I, it ran a route mileage of more than 1500 mi, and employed 111,000 people. In 1913, the company achieved a total revenue of £17,219,060 with working expenses of £11,322,164.

On 1 January 1922, one year before it amalgamated with other railways to create the London, Midland and Scottish Railway (LMS), the LNWR amalgamated with the Lancashire and Yorkshire Railway (including its subsidiary the Dearne Valley Railway) and at the same time absorbed the North London Railway and the Shropshire Union Railways and Canal Company, both of which were previously controlled by the LNWR. With this, the LNWR achieved a route mileage (including joint lines, and lines leased or worked) of 2707.88 mi.

The company built a war memorial in the form of an obelisk outside Euston station to commemorate the 3,719 of its employees who died in the First World War. After the Second World War, the names of the LMS's casualties were added to the LNWR's memorial.

The LNWR were also involved in the mass manufacture of replacement legs in the mid 19th century and the early 20th century. This is due-to the routine demand for prostheses for disabled staff. Serious injuries that resulted in the loss of limbs were common at this time with over 4,963 casualties in the year of 1910 on the LNWR alone, and over 25,000 injuries across the whole industry, manufacturing prostheses resulted in self-sufficiency for the company.

Electrification
From 1909 to 1922, the LNWR undertook a large-scale project to electrify the whole of its London inner-suburban network. The London and North Western Railway London inner-suburban network, encompassed the lines from London Broad Street to Richmond, London Euston to Watford, with branch lines such as Watford to Croxley Green. There were also links to the District Railway at Earl's Court and over the route to Richmond. With the Bakerloo Tube Line being extended over the Watford DC lines, the railway was electrified at 630 V DC fourth rail. The electricity was generated at the LNWR's power station in Stonebridge Park and a depot built at Croxley Green.

Successors
The LNWR became a constituent of the London, Midland and Scottish (LMS) railway when the railways of Great Britain were merged in the grouping of 1923. Ex-LNWR lines formed the core of the LMS's Western Division.

Nationalisation followed in 1948, with the English and Welsh lines of the LMS becoming the London Midland Region of British Railways. Some former LNWR routes were subsequently closed, including the lines running east to west across the Midlands (e.g. Peterborough to Northampton and Cambridge to Oxford), but others were developed as part of the Inter City network, such as the main lines from London to Birmingham, Manchester, Liverpool and Carlisle, collectively known in the modern era as the West Coast Main Line. These were electrified in the 1960s and 1970s, and further upgraded in the 1990s and 2000s, with trains now running at up to 125 mph. Other LNWR lines survive as part of commuter networks around major cities such as Birmingham and Manchester. In 2017 it was announced that the new franchisee for the West Midlands and semi-fast West Coast services between London and North West England would utilise the brand London Northwestern Railway as an homage to the LNWR.

Acquisitions
• Anglesey Central Railway, 1876

• Ashby and Nuneaton Joint Railway (partnership with the Midland Railway) 1873

• Aylesbury Railway, 1846

• Bedford and Cambridge Railway, 1865

• Birkenhead Railway, 1861 (jointly with GWR)

• Birmingham, Wolverhampton and Stour Valley Railway, 1847 (the Stour Valley Line)

• Brynmawr and Blaenavon Railway, 1869

• Brynmawr and Western Valleys Railway, 1902 (jointly with GWR)

• Buckinghamshire Railway, 1847

• Cannock Chase Railways, 1863

• Cannock Mineral Railway, 1869

• Carnarvon and Llanberis Railway, 1870

• Carnarvonshire Railway, 1870

• Central Wales Railway, 1868

• Central Wales and Carmarthen Junction Railway, 1891

• Central Wales Extension Railway, 1868

• Chester and Holyhead Railway, 1858

• Cockermouth and Workington Railway, 1866

• Conway and Llanrwst Railway, 1867

• Cromford and High Peak Railway, 1862

• Denbigh, Ruthin and Corwen Railway, 1879

• Dundalk, Newry and Greenore Railway, 1869

• Fleetwood, Preston and West Riding Junction Railway, 1867 (jointly with Lancashire and Yorkshire Railway)

• Hampstead Junction Railway, 1867

• Harrow and Stanmore Railway, 1899

• Huddersfield and Manchester Railway and Canal, 1847

• Knighton Railway, 1863

• Lancashire and Yorkshire Railway, 1921

• Lancashire Union Railway, 1883 (jointly with Lancashire and Yorkshire Railway)

• Lancaster and Carlisle Railway, 1859

• Leeds, Dewsbury and Manchester Railway, 1847

• Ludlow and Clee Hill Railway, 1892 (jointly with GWR)

• Manchester South Junction and Altrincham Railway, 1849 (jointly with Sheffield, Ashton-under-Lyne and Manchester Railway)

• Merthyr, Tredegar and Abergavenny Railway, 1862

• Nerquis Railway, 1866

• Newport Pagnell Railway, 1875

• North and South Western Junction Railway, 1871 (jointly with the Midland Railway and the North London Railway)

• North London Railway, 1909 (NLR retained own Board)

• Northampton and Peterborough Railway, 1846

• Oldham, Ashton and Guide Bridge Railway, 1862 (jointly with the Manchester, Sheffield and Lincolnshire Railway)

• Portpatrick and Wigtownshire Railway, 1885 (jointly with Midland Railway, Caledonian Railway and Glasgow and South Western Railway)

• Preston and Wyre Railway, 1847 (jointly with Lancashire and Yorkshire Railway)

• Rugby and Leamington Railway, 1848

• Rugby and Stamford Railway, 1846

• St George's Harbour, 1861

• St Helens Canal and Railway, 1864

• Shrewsbury and Hereford Railway, 1862 (jointly with GWR and West Midland Railway)

• Shrewsbury and Welshpool Railway, 1864 (jointly with GWR from 1865)

• Shropshire Union Railways and Canal, 1847

• Sirhowy Railway, 1876

• South Leicestershire Railway, 1867

• South Staffordshire Railway, 1861

• Stockport, Disley and Whaley Bridge Railway, 1866

• Trent Valley Railway, 1847

• Tenbury Railway, 1866 (jointly with GWR from 1869)

• Vale of Clwyd Railway, 1867

• Vale of Towy Railway, 1884 (jointly with GWR from 1889)

• Warrington and Stockport Railway, 1859

• Watford and Rickmansworth Railway, 1881

• West London Extension Railway, 1859 (jointly with GWR, LSWR and LBSCR)

• Whitehaven, Cleator and Egremont Railway, 1877 (jointly with Furness Railway from 1878)

• Whitehaven Junction Railway, 1866

Locomotives

The LNWR's main engineering works were at Crewe (locomotives), Wolverton (carriages) and Earlestown (wagons). Locomotives were usually painted green at first, but in 1873 black was adopted as the standard livery. This finish has been described as "blackberry black".

Accidents and incidents
Major accidents on the LNWR include:
 * On 26 March 1850, the boiler of a locomotive exploded at Wolverton, Buckinghamshire due to tampering of the safety valves. One person was injured.
 * On 30 April 1851 a train returning from Chester Races broke down in Sutton tunnel, and the following train ran into it. Six passengers were killed.
 * On 6 September 1851 a train run for the Great Exhibition returning from Euston to Oxford derailed at Bicester and six passengers were killed.
 * On 6 March 1853, the boiler of a locomotive exploded at Longsight, Lancashire. Six people were killed and the engine shed was severely damaged.
 * On 27 August 1860 a passenger train collided with a goods train at Craven Arms and one passenger was killed.
 * On 16 November 1860 the Irish night mail ran into a cattle train at Atherstone. The fireman of the mail train, and nine drovers in the cattle train were killed.
 * On 11 June 1861, a cast-iron bridge collapsed under a freight train at Leek Wootton, Warwickshire. Both engine crew were killed.
 * On 2 September 1861 a ballast train came out of a siding onto the main line just past Kentish Town Junction without the signalman's permission, and an excursion train from Kew ran past the signals and collided with it, resulting in the deaths of fourteen passengers and two employees.
 * On 29 June 1867, a passenger train ran into the rear of a coal train at Warrington, Cheshire due to a pointsman's error which was compounded by the lack of interlocking between points and signals. Eight people were killed and 33 were injured.
 * On 20 August 1868, a rake of wagons ran away from Llandulas, Denbighshire during shunting operations. The wagons subsequently collided with the Irish Mail at Abergele, Denbighshire. Kerosene being carried in the wagons set the wreck on fire. Thirty-three people were killed in what was then the deadliest rail accident to have occurred in the United Kingdom.
 * On 14 September 1870, a mail train was diverted into a siding at Tamworth station, Staffordshire due to a signalman's error. The train crashed through the buffers and ended up in the River Anker, killing three people.
 * In 1870, a North Eastern Railway freight train overran signals and collided with a passenger train at St. Nicholas Crossing, Carlisle, Cumberland. Five people were killed. The driver of the freight train was intoxicated.
 * On 26 November 1870, a mail train was in a rear-end collision with a freight train at Harrow, Middlesex. Eight people were killed.
 * On 2 August 1873, a passenger train derailed at Wigan, Lancashire due to excessive speed. Thirteen people were killed and 30 were injured.
 * On 22 December 1894, a wagon was derailed fouling the main line at Chelford, Cheshire. It was run into by an express passenger train, which was derailed. Fourteen people were killed and 48 were injured.
 * On 15 August 1895, an express passenger train was derailed at Preston, Lancashire due to excessive speed on a curve. One person was killed.
 * On 12 January 1899, An express freight train was derailed at Penmaenmawr, Caernarfonshire due to the trackbed being washed away by the sea during a storm. Both locomotive crew were killed.
 * On 15 August 1903, two passenger trains collided at Preston, Lancashire due to faulty points.
 * On 15 October 1907, a mail train was derailed at Shrewsbury, Shropshire due to excessive speed on a curve. Eighteen people were killed.
 * On 19 August 1909, a passenger train was derailed at Friezland, West Yorkshire. Two people were killed.
 * On 5 December 1910, a passenger train was in a rear-end collision at Willesden Junction, London. Three people were killed and more than 40 were injured.
 * On 17 September 1912, the driver of an express train misread signals at Ditton Junction, Cheshire. The train was derailed when it ran over points at an excessive speed. Fifteen people were killed.
 * On 14 August 1915, an express passenger train was derailed at Weedon, Northamptonshire due to a locomotive defect. Ten people were killed and 21 were injured.
 * On 11 November 1921, the boiler of a locomotive exploded at Buxton, Derbyshire. Two people were killed.

Minor incidents include:
 * In 1900, wagons of a permanent way train carrying sleepers were set on fire by the heat of the sun at Earlestown, Lancashire, destroying some of them.

Ships
The LNWR operated ships on Irish Sea crossings between Holyhead and Dublin, Howth, Kingstown or Greenore. At Greenore, the LNWR built and operated the Dundalk, Newry and Greenore Railway to link the port with the Belfast–Dublin line operated by the Great Northern Railway.

The LNWR also operated a joint service with the Lancashire & Yorkshire Railway from Fleetwood to Belfast and Derry.

Chairmen of the Board of Directors

 * 1846–1852 – George Glyn, later 1st Baron Wolverton
 * 1852–1853 – Major-General George Anson
 * 1853–1861 – Marquess of Chandos, later 3rd Duke of Buckingham and Chandos
 * 1861 – Admiral Constantine Richard Moorsom
 * 1861–1891 – Richard Moon, Sir Richard Moon from 1887
 * 1891–1911 – The Lord Stalbridge
 * 1911–1921 – Gilbert Claughton, Sir Gilbert Claughton from 1912
 * 1921–1923 – Hon. Charles N. Lawrence, later Baron Lawrence of Kingsgate

Members of the Board of Directors

 * John Pares Bickersteth
 * Michael Linning Melville
 * Frederick Baynes
 * Henry Booth
 * John Albert Bright
 * Ralph Brocklebank
 * Sir Thomas Brooke, 1st Baronet
 * Philip Henry Chambres
 * William E. Dorrington
 * Edmund Faber, 1st Baron Faber
 * Alfred Fletcher
 * Samuel Robert Graves
 * Rupert Guinness, 2nd Earl of Iveagh
 * Theodore Julius Hare
 * John Hick
 * The Hon. A. H. Holland-Hibbert
 * Sir William Houldsworth, 1st Baronet
 * J. Bruce Ismay
 * Lieut-Col. Amelius Lockwood, 1st Baron Lambourne
 * The Hon. William Lowther
 * Brigadier-General Lewis Vivian Loyd
 * Miles MacInnes
 * Edward Nettlefold
 * David Plunket, 1st Baron Rathmore
 * Cromartie Sutherland-Leveson-Gower, 4th Duke of Sutherland
 * Henry Ward

General Managers

 * 1846–1858 – Captain Mark Huish
 * 1858–1874 – William Cawkwell
 * 1874–1893 – Sir George Findlay (knighted 1892)
 * 1893–1908 – Sir Frederick Harrison (knighted in 1902)
 * 1909–1914 – Sir Frank Ree (knighted 1913)
 * 1914     – Sir Robert Turnbull (knighted 1913)
 * 1914–1919 – Sir Guy Calthrop (made a baronet 1918)
 * 1919–1920 – Isaac Thomas Williams (knighted c.1919)
 * 1920–1923 – Arthur Watson

Chief Civil Engineers

 * Robert Stephenson until 1859
 * William Baker 1859 – 1878
 * Francis Stevenson 1879 – 1902
 * Edward Baylies Thornhill 1902 – 1909
 * Ernest Frederic Crosbie Trench 1909 – 1923 (afterwards chief engineer of the London, Midland and Scottish Railway)

Locomotive Superintendents and Chief Mechanical Engineers
Southern Division:
 * 1846–1847 – Edward Bury
 * 1847–1862 – James McConnell

North Eastern Division: NE Division became part of N Division in 1857.
 * 1846–1857 – John Ramsbottom

Northern Division:
 * 1846–1857 – Francis Trevithick
 * 1857–1862 – John Ramsbottom

Northern and Southern Divisions amalgamated from April 1862:
 * 1862–1871 – John Ramsbottom
 * 1871–1903 – Francis William Webb
 * 1903–1909 – George Whale
 * 1909–1920 – Charles Bowen Cooke
 * 1920–1921 – Hewitt Pearson Montague Beames
 * 1922 – George Hughes (ex-Lancashire and Yorkshire Railway)

Solicitors

 * 1830–1861 – Samuel Carter, with continuing role for subsidiary companies

Preservation

 * Sections of the former L&NWR are preserved as the Battlefield Line Railway, Nene Valley Railway and Northampton & Lamport Railway, the latter giving the name Premier Line to its quarterly journal.
 * A section of the former L&NWR line and station buildings are preserved at Quainton near Aylesbury. It is administered by the Buckinghamshire Railway preservation Society and houses some original L&NWR rolling stock in the former Oxford Rewley Road station. It regularly runs steam trains using various locomotives.

title: London and North Western Railway


text:
Grand Junction Railway

The Grand Junction Railway (GJR) was an early railway company in the United Kingdom, which existed between 1833 and 1846. The line built by the company, which opened in 1837, linked the Liverpool and Manchester Railway to Birmingham via Warrington, Crewe, Stafford and Wolverhampton. This was the first trunk railway to be completed in England, and arguably the world's first long-distance railway with steam traction. It terminated at Curzon Street Station in Birmingham, which it shared with the London and Birmingham Railway (L&BR), whose adjacent platforms gave an interchange with full connectivity (with through carriages) between Liverpool, Manchester and London.

The company merged with its business partners in 1846 to form the London and North Western Railway (LNWR). The lines which comprised the GJR now form the central section of the West Coast Main Line.

History

The Grand Junction Railway Company was established in the second half of 1832 by the consolidation of two rival companies: the Birmingham and Liverpool Railway Company and the Liverpool and Birmingham Railway Company. Authorised by Parliament on 6 May 1833 and designed by George Stephenson and Joseph Locke, the Grand Junction Railway opened for business on 4 July 1837, running for 82 mi from Birmingham through Wolverhampton (via Perry Barr and Bescot), Stafford, Crewe, and Warrington, then via the existing Warrington and Newton Railway to join the Liverpool and Manchester Railway at a triangular junction at Newton Junction. The GJR established its chief engineering works at Crewe, relocating there from Edge Hill, in Liverpool.

It began operation with a temporary Birmingham terminus at Vauxhall, The travelling post office where mail was sorted on a moving train was instituted on the Grand Junction Railway in January 1838. Using a converted horse-box, it was carried out at the suggestion of Frederick Karstadt, a General Post Office surveyor. Karstadt's son was one of two mail clerks who did the sorting.

When the London and Birmingham Railway opened on 17 September 1838, services were routed to and from Curzon Street station which it shared with the Grand Junction Railway, the platforms of which were adjacent, providing a link between Liverpool, Manchester and London. The route between Curzon Street railway station and Vauxhall primarily consisted of the Birmingham Viaduct. It consisted of 28 arches, each 31 ft wide and 28 ft tall and crossed the River Rea. In October 1838, the Liverpool Mercury reported that "It is confidently expected, that after the ensuing winter is over, and the embankments on the London and Birmingham Line are well settled down, first class trains between Liverpool and Manchester and London will not occupy more than nine hours in the journey. This being accomplished, what further improvement could be desired between London and Lancashire?" In 1840, the GJR absorbed the Chester and Crewe Railway soon before it began operation. Considering itself as part of a grand railway network, the company encouraged the development of the North Union Railway which extended the tracks onward to Preston, and it also invested in the Lancaster and Carlisle Railway and the Caledonian Railway. In 1845, the GJR merged with the Liverpool and Manchester Railway, and consolidated its position by buying the North Union Railway in association with the Manchester and Leeds Railway.

In 1841, the company appointed Captain Mark Huish as the secretary of the railway. Huish was ruthless in the development of the business and contributed significantly to the company's success.

Profits
The GJR was very profitable, paying dividends of at least 10% from its beginning and having a final capital value of more than £5.75 million (equivalent to £ million now) when it merged with the London and Birmingham Railway and Manchester and Birmingham Railway companies to become the London and North Western Railway in 1846, which in turn formed part of the London Midland and Scottish Railway in 1923.

Locomotives

One locomotive, Columbine, a 2-2-2 tender engine built in 1845 at Crewe Works, is preserved at the Science Museum. Designed by Alexander Allan, it was the first of the GJR's standard 'Crewe-type' engines, with outside cylinders, and carried fleet number 49. It was withdrawn from service in 1902 by the LNWR, carrying their number 1868.

title: Grand Junction Railway


text:
Stirling engine

A Stirling engine is a heat engine that is operated by the cyclic expansion and contraction of air or other gas (the working fluid) by exposing it to different temperatures, resulting in a net conversion of heat energy to mechanical work.

More specifically, the Stirling engine is a closed-cycle regenerative heat engine, with a permanent gaseous working fluid. Closed-cycle, in this context, means a thermodynamic system in which the working fluid is permanently contained within the system. Regenerative describes the use of a specific type of internal heat exchanger and thermal store, known as the regenerator. Strictly speaking, the inclusion of the regenerator is what differentiates a Stirling engine from other closed-cycle hot air engines.

In the Stirling engine, a working fluid (e.g. air) is heated by energy supplied from outside the engine's interior space (cylinder). As the fluid expands, mechanical work is extracted by a piston, which is coupled to a displacer. The displacer moves the working fluid to a different location within the engine, where it is cooled, which creates a partial vacuum at the working cylinder, and more mechanical work is extracted. The displacer moves the cooled fluid back to the hot part of the engine, and the cycle continues.

A unique feature is the regenerator, which acts as a temporary heat store by retaining heat within the machine rather than dumping it into the heat sink, thereby increasing its efficiency.

The heat is supplied from the outside, so the hot area of the engine can be warmed with any external heat source. Similarly, the cooler part of the engine can be maintained by an external heat sink, such as running water or air flow. The gas is permanently retained in the engine, allowing a gas with the most-suitable properties to be used, such as helium or hydrogen. There are no intake and no exhaust gas flows so the machine is practically silent.

The machine is reversible so that if the shaft is turned by an external power source a temperature difference will develop across the machine; in this way it acts as a heat pump.

The Stirling engine was invented by Scotsman Robert Stirling in 1816 as an industrial prime mover to rival the steam engine, and its practical use was largely confined to low-power domestic applications for over a century.

Contemporary investment in renewable energy, especially solar energy, has given rise to its application within concentrated solar power and as a heat pump.

Early hot air engines
Robert Stirling is considered one of the fathers of hot air engines, along with earlier innovators such as Guillaume Amontons, who built the first working hot air engine in 1699.

Amontons was later followed by Sir George Cayley. This engine type was of those in which the fire is enclosed, and fed by air pumped in beneath the grate in sufficient quantity to maintain combustion, while by far the largest portion of the air enters above the fire, to be heated and expanded; the whole, together with the products of combustion, then acts on the piston, and passes through the working cylinder; and the operation being one of simple mixture only, no heating surface of metal is required, the air to be heated being brought into immediate contact with the fire.

Stirling came up with a first air engine in 1816. The principle of the Stirling Air Engine differs from that of Sir George Cayley (1807), in which the air is forced through the furnace and exhausted, whereas in Stirling's engine the air works in a closed circuit. The inventor devoted most of his attention to that.

A 2 hp engine, built in 1818 for pumping water at an Ayrshire quarry, continued to work for some time until a careless attendant allowed the heater to become overheated. This experiment proved to the inventor that, owing to the low working pressure obtainable, the engine could only be adapted to low power for which there was, at that time, no demand.

The Stirling 1816 patent was also about an "economiser," which is the predecessor of the regenerator. In this patent (# 4081) he describes the "economiser" technology and several applications where such technology can be used. Out of them came a new arrangement for a hot air engine.

With his brother James, Stirling patented a second hot air engine in 1827. They inverted the design so that the hot ends of the displacers were underneath the machinery, and they added a compressed air pump so the air within could be increased in pressure to around 20 atm.

The Stirling brothers were followed shortly after (1828) by Parkinson & Crossley and Arnott in 1829.

These precursors, including Ericsson, have brought to the world the hot air engine technology and its enormous advantages over the steam engine. Each came with his own specific technology, and although the Stirling engine and the Parkinson & Crossley engines were quite similar, Robert Stirling distinguished himself by inventing the regenerator.

Parkinson and Crossley introduced the principle of using air of greater density than that of the atmosphere and so obtained an engine of greater power in the same compass. James Stirling followed this same idea when he built the famous Dundee engine.

The Stirling patent of 1827 was the base of the Stirling third patent of 1840. The changes from the 1827 patent were minor but essential, and this third patent led to the Dundee engine.

James Stirling presented his engine to the Institution of Civil Engineers in 1845, the first engine of this kind which, after various modifications, was efficiently constructed and heated, had a cylinder of 12 inch in diameter, with a length of stroke of 2 ft, and made 40 strokes or revolutions in a minute (40 rpm). This engine moved all the machinery at the Dundee Foundry Company's works for eight or ten months, and was previously found capable of raising 320,000 kg (700,000 lbs) 60 cm (2 ft) in a minute, a power of approximately 21 hp. Finding this power insufficient for their works, the Dundee Foundry Company erected the second engine with a cylinder of 16 inch in diameter, a stroke of 4 ft, and making 28 strokes in a minute. When this engine had been in continuous operation for over two years it had not only performed the work of the foundry in the most satisfactory manner but had been tested (by a friction brake on a third mover) to the extent of lifting nearly 687 t, approximately 45 hp.

Invention and early development
The Stirling engine (or Stirling's air engine as it was known at the time) was invented and patented in 1816. It followed earlier attempts at making an air engine but was probably the first put to practical use when, in 1818, an engine built by Stirling was employed pumping water in a quarry. The main subject of Stirling's original patent was a heat exchanger, which he called an "economiser" for its enhancement of fuel economy in a variety of applications. The patent also described in detail the employment of one form of the economiser in his unique closed-cycle air engine design in which application it is now generally known as a "regenerator". Subsequent development by Robert Stirling and his brother James, an engineer, resulted in patents for various improved configurations of the original engine including pressurization, which by 1843, had sufficiently increased power output to drive all the machinery at a Dundee iron foundry.

A paper presented by James Stirling in June 1845 to the Institution of Civil Engineers stated that his aims were not only to save fuel but also to create a safer alternative to the steam engines of the time, whose boilers frequently exploded, causing many injuries and fatalities. This has, however, been disputed.

The need for Stirling engines to run at very high temperatures to maximize power and efficiency exposed limitations in the materials of the day, and the few engines that were built in those early years suffered unacceptably frequent failures (albeit with far less disastrous consequences than boiler explosions). For example, the Dundee foundry engine was replaced by a steam engine after three hot cylinder failures in four years.

Later 19th century

Subsequent to the replacement of the Dundee foundry engine there is no record of the Stirling brothers having any further involvement with air engine development, and the Stirling engine never again competed with steam as an industrial scale power source. (Steam boilers were becoming safer, e.g. the Hartford Steam Boiler and steam engines more efficient, thus presenting less of a target for rival prime movers). However, beginning about 1860, smaller engines of the Stirling/hot air type were produced in substantial numbers for applications in which reliable sources of low to medium power were required, such as pumping air for church organs or raising water. These smaller engines generally operated at lower temperatures so as not to tax available materials, and so were relatively inefficient. Their selling point was that unlike steam engines, they could be operated safely by anybody capable of managing a fire. The 1906 Rider-Ericsson Engine Co. catalog claimed that "any gardener or ordinary domestic can operate these engines and no licensed or experienced engineer is required". Several types remained in production beyond the end of the century, but apart from a few minor mechanical improvements the design of the Stirling engine in general stagnated during this period.

20th-century revival

During the early part of the 20th century, the role of the Stirling engine as a "domestic motor" was gradually taken over by electric motors and small internal combustion engines. By the late 1930s, it was largely forgotten, only produced for toys and a few small ventilating fans.

Around that time, Philips was seeking to expand sales of its radios into parts of the world where grid electricity and batteries were not consistently available. Philips' management decided that offering a low-power portable generator would facilitate such sales and asked a group of engineers at the company's research lab in Eindhoven to evaluate alternative ways of achieving this aim. After a systematic comparison of various prime movers, the team decided to go forward with the Stirling engine, citing its quiet operation (both audibly and in terms of radio interference) and ability to run on a variety of heat sources (common lamp oil – "cheap and available everywhere" – was favored). They were also aware that, unlike steam and internal combustion engines, virtually no serious development work had been carried out on the Stirling engine for many years and asserted that modern materials and know-how should enable great improvements.

By 1951, the 180/200 W generator set designated MP1002CA (known as the "Bungalow set") was ready for production and an initial batch of 250 was planned, but soon it became clear that they could not be made at a competitive price. Additionally, the advent of transistor radios and their much lower power requirements meant that the original reason for the set was disappearing. Approximately 150 of these sets were eventually produced. Some found their way into university and college engineering departments around the world, giving generations of students a valuable introduction to the Stirling engine; a letter dated March 1961 from Research and Control Instruments Ltd. London WC1 to North Devon Technical College, offering "remaining stocks... to institutions such as yourselves... at a special price of £75 net".

In parallel with the Bungalow set, Philips developed experimental Stirling engines for a wide variety of applications and continued to work in the field until the late 1970s, but only achieved commercial success with the "reversed Stirling engine" cryocooler. They filed a large number of patents and amassed a wealth of information which they licensed to other companies and which formed the basis of much of the development work in the modern era.

In 1996, the Swedish navy commissioned three Gotland-class submarines. On the surface, these boats are propelled by marine diesel engines; however, when submerged they use a Stirling-driven generator developed by Swedish shipbuilder Kockums to recharge batteries and provide electrical power for propulsion. A supply of liquid oxygen is carried to support burning of diesel fuel to power the engine. Stirling engines are also fitted to Swedish Södermanland-class submarines, the Archer-class submarines in service in Singapore, and the Japanese Sōryū-class submarines, with the engines license-built by Kawasaki Heavy Industries. In a submarine application, the Stirling engine offers the advantage of being exceptionally quiet when running.

21st-century developments
By the turn of the 21st century, Stirling engines were used in the dish version of Concentrated Solar Power systems. A mirrored dish similar to a very large satellite dish directs and concentrates sunlight onto a thermal receiver, which absorbs and collects the heat and using a fluid transfers it into the Stirling engine. The resulting mechanical power is then used to run a generator or alternator to produce electricity.

The core component of micro combined heat and power (CHP) units can be formed by a Stirling cycle engine, as they are more efficient and safer than a comparable steam engine. By 2003, CHP units were being commercially installed in domestic applications, such as home electrical generators.

In 2013, an article was published about scaling laws of free-piston Stirling engines based on six characteristic dimensionless groups.

Name and classification

Robert Stirling patented the first practical example of a closed-cycle hot air engine in 1816, and it was suggested by Fleeming Jenkin as early as 1884 that all such engines should therefore generically be called Stirling engines. This naming proposal found little favour, and the various types on the market continued to be known by the name of their individual designers or manufacturers, e.g., Rider's, Robinson's, or Heinrici's (hot) air engine. In the 1940s, the Philips company was seeking a suitable name for its own version of the 'air engine', which by that time had been tested with working fluids other than air, and decided upon 'Stirling engine' in April 1945. However, nearly thirty years later, Graham Walker still had cause to bemoan the fact such terms as hot air engine remained interchangeable with Stirling engine, which itself was applied widely and indiscriminately, a situation that continues.

Like the steam engine, the Stirling engine is traditionally classified as an external combustion engine, as all heat transfers to and from the working fluid take place through a solid boundary (heat exchanger) thus isolating the combustion process and any contaminants it may produce from the working parts of the engine. This contrasts with an internal combustion engine, where heat input is by combustion of a fuel within the body of the working fluid. Most of the many possible implementations of the Stirling engine fall into the category of reciprocating piston engine.

Theory

The idealised Stirling cycle consists of four thermodynamic processes acting on the working fluid:

 * 1) Isothermal expansion. The expansion-space and associated heat exchanger are maintained at a constant high temperature, and the gas undergoes near-isothermal expansion absorbing heat from the hot source.
 * 2) Constant-volume (known as isovolumetric or isochoric) heat-removal. The gas is passed through the regenerator, where it cools, transferring heat to the regenerator for use in the next cycle.
 * 3) Isothermal compression. The compression space and associated heat exchanger are maintained at a constant low temperature so the gas undergoes near-isothermal compression rejecting heat to the cold sink
 * 4) Constant-volume (known as isovolumetric or isochoric) heat-addition. The gas passes back through the regenerator where it recovers much of the heat transferred in process 2, heating up on its way to the expansion space.

With the ideal, maximally efficient, Stirling engine, for the thermal reservoirs the ratio of the heat in to the heat out is the efficiency of the ideal Carnot cycle. This is the Carnot efficiency, which is the ratio of the Kelvin temperatures of the cold to the hot reservoir. With the ideal, maximally efficient, Carnot cycle, the isochores (constant volume) are replaced by adiabats (no net heat transfer because no heat transfer). For the ideal Stirling cycle, whatever heat enters during the isochoric leg where the temperature increases is totally released during the isochoric leg where the temperature decreases (no net heat transfer).

The engine is designed so the working gas is generally compressed in the colder portion of the engine and expanded in the hotter portion resulting in a net conversion of heat into work. An internal regenerative heat exchanger increases the Stirling engine's thermal efficiency compared to simpler hot air engines lacking this feature.

The Stirling engine uses the temperature difference between its hot end and cold end to establish a cycle of a fixed mass of gas, heated and expanded, and cooled and compressed, thus converting thermal energy into mechanical energy. The greater the temperature difference between the hot and cold sources, the greater the thermal efficiency. The maximum theoretical efficiency is equivalent to that of the Carnot cycle, but the efficiency of real engines is less than this value because of friction and other losses.

Since the Stirling engine is a closed cycle, it contains a fixed mass of gas called the "working fluid", most commonly air, hydrogen or helium. In normal operation, the engine is sealed and no gas enters or leaves; no valves are required, unlike other types of piston engines. The Stirling engine, like most heat engines, cycles through four main processes: cooling, compression, heating, and expansion. This is accomplished by moving the gas back and forth between hot and cold heat exchangers, often with a regenerator between the heater and cooler. The hot heat exchanger is in thermal contact with an external heat source, such as a fuel burner, and the cold heat exchanger is in thermal contact with an external heat sink, such as air fins. A change in gas temperature causes a corresponding change in gas pressure, while the motion of the piston makes the gas alternately expand and compress.

The gas follows the behaviour described by the gas laws that describe how a gas's pressure, temperature, and volume are related. When the gas is heated, the pressure rises (because it is in a sealed chamber) and this pressure then acts on the power piston to produce a power stroke. When the gas is cooled the pressure drops and this drop means that the piston needs to do less work to compress the gas on the return stroke. The difference in work between the strokes yields a net positive power output.

When one side of the piston is open to the atmosphere, the operation is slightly different. As the sealed volume of working gas comes in contact with the hot side, it expands, doing work on both the piston and on the atmosphere. When the working gas contacts the cold side, its pressure drops below atmospheric pressure and the atmosphere pushes on the piston and does work on the gas.

Components

As a consequence of closed-cycle operation, the heat driving a Stirling engine must be transmitted from a heat source to the working fluid by heat exchangers and finally to a heat sink. A Stirling engine system has at least one heat source, one heat sink and up to five heat exchangers. Some types may combine or dispense with some of these.

Heat source

The heat source may be provided by the combustion of a fuel and, since the combustion products do not mix with the working fluid and hence do not come into contact with the internal parts of the engine, a Stirling engine can run on fuels that would damage other engines types' internals, such as landfill gas, which may contain siloxane that could deposit abrasive silicon dioxide in conventional engines.

Other suitable heat sources include concentrated solar energy, geothermal energy, nuclear energy, waste heat and bioenergy. If solar power is used as a heat source, regular solar mirrors and solar dishes may be utilised. The use of Fresnel lenses and mirrors has also been advocated, for example in planetary surface exploration. Solar powered Stirling engines are increasingly popular as they offer an environmentally sound option for producing power while some designs are economically attractive in development projects.

Heat exchangers
Designing Stirling engine heat exchangers is a balance between high heat transfer with low viscous pumping losses, and low dead space (unswept internal volume). Engines that operate at high powers and pressures require that heat exchangers on the hot side be made of alloys that retain considerable strength at high temperatures and that don't corrode or creep.

In small, low power engines the heat exchangers may simply consist of the walls of the respective hot and cold chambers, but where larger powers are required a greater surface area is needed to transfer sufficient heat. Typical implementations are internal and external fins or multiple small bore tubes for the hot side, and a cooler using a liquid (like water) for the cool side.

Regenerator
In a Stirling engine, the regenerator is an internal heat exchanger and temporary heat store placed between the hot and cold spaces such that the working fluid passes through it first in one direction then the other, taking heat from the fluid in one direction, and returning it in the other. It can be as simple as metal mesh or foam, and benefits from high surface area, high heat capacity, low conductivity and low flow friction. Its function is to retain within the system that heat which would otherwise be exchanged with the environment at temperatures intermediate to the maximum and minimum cycle temperatures, thus enabling the thermal efficiency of the cycle (though not of any practical engine ) to approach the limiting Carnot efficiency.

The primary effect of regeneration in a Stirling engine is to increase the thermal efficiency by 'recycling' internal heat which would otherwise pass through the engine irreversibly. As a secondary effect, increased thermal efficiency yields a higher power output from a given set of hot and cold end heat exchangers. These usually limit the engine's heat throughput. In practice this additional power may not be fully realized as the additional "dead space" (unswept volume) and pumping loss inherent in practical regenerators reduces the potential efficiency gains from regeneration.

The design challenge for a Stirling engine regenerator is to provide sufficient heat transfer capacity without introducing too much additional internal volume ('dead space') or flow resistance. These inherent design conflicts are one of many factors that limit the efficiency of practical Stirling engines. A typical design is a stack of fine metal wire meshes, with low porosity to reduce dead space, and with the wire axes perpendicular to the gas flow to reduce conduction in that direction and to maximize convective heat transfer.

The regenerator is the key component invented by Robert Stirling, and its presence distinguishes a true Stirling engine from any other closed-cycle hot air engine. Many small 'toy' Stirling engines, particularly low-temperature difference (LTD) types, do not have a distinct regenerator component and might be considered hot air engines; however, a small amount of regeneration is provided by the surface of the displacer itself and the nearby cylinder wall, or similarly the passage connecting the hot and cold cylinders of an alpha configuration engine.

Heat sink
The larger the temperature difference between the hot and cold sections of a Stirling engine, the greater the engine's efficiency. The heat sink is typically the environment the engine operates in, at ambient temperature. In the case of medium- to high-power engines, a radiator is required to transfer the heat from the engine to the ambient air. Marine engines have the advantage of using cool ambient sea, lake, or river water, which is typically cooler than ambient air. In the case of combined heat and power systems, the engine's cooling water is used directly or indirectly for heating purposes, raising efficiency.

Alternatively, heat may be supplied at ambient temperature and the heat sink maintained at a lower temperature by such means as cryogenic fluid (see Liquid nitrogen economy) or iced water.

Displacer
The displacer is a special-purpose piston, used in Beta and Gamma type Stirling engines, to move the working gas back and forth between the hot and cold heat exchangers. Depending on the type of engine design, the displacer may or may not be sealed to the cylinder; i.e., it may be a loose fit within the cylinder, allowing the working gas to pass around it as it moves to occupy the part of the cylinder beyond. The Alpha type engine has a high stress on the hot side, that's why so few inventors started to use a hybrid piston for that side. The hybrid piston has a sealed part as a normal Alpha type engine, but it has a connected displacer part with smaller diameter as the cylinder around that. The compression ratio is a bit smaller than in the original Alpha type engines, but the stress factor is pretty low on the sealed parts.

Configurations
The three major types of Stirling engines are distinguished by the way they move the air between the hot and cold areas:

 * 1) The alpha configuration has two power pistons, one in a hot cylinder, one in a cold cylinder, and the gas is driven between the two by the pistons; it is typically in a V-formation with the pistons joined at the same point on a crankshaft.
 * 2) The beta configuration has a single cylinder with a hot end and a cold end, containing a power piston and a 'displacer' that drives the gas between the hot and cold ends. It is typically used with a rhombic drive to achieve the phase difference between the displacer and power pistons, but they can be joined 90 degrees out of phase on a crankshaft.
 * 3) The gamma configuration has two cylinders: one containing a displacer, with a hot and a cold end, and one for the power piston; they are joined to form a single space, so the cylinders have equal pressure; the pistons are typically in parallel and joined 90 degrees out of phase on a crankshaft.

Alpha

An alpha Stirling contains two power pistons in separate cylinders, one hot and one cold. The hot cylinder is situated inside the high-temperature heat exchanger and the cold cylinder is situated inside the low-temperature heat exchanger. This type of engine has a high power-to-volume ratio but has technical problems because of the usually high temperature of the hot piston and the durability of its seals. In practice, this piston usually carries a large insulating head to move the seals away from the hot zone at the expense of some additional dead space. The crank angle has a major effect on efficiency and the best angle frequently must be found experimentally. An angle of 90° frequently locks.

A four-step description of the process is as follows:

 * 1) Most of the working gas is in the hot cylinder and has more contact with the hot cylinder's walls. This results in overall heating of the gas. Its pressure increases and the gas expands. Because the hot cylinder is at its maximum volume and the cold cylinder is at mid stroke (partial volume), the volume of the system is increased by expansion into the cold cylinder.
 * 2) The system is at its maximum volume and more gas has contact with the cold cylinder. This cools the gas, lowering its pressure. Because of flywheel momentum or other piston pairs on the same shaft, the hot cylinder begins an upstroke reducing the volume of the system.
 * 3) Almost all the gas is now in the cold cylinder and cooling continues. This continues to reduce the pressure of the gas and cause contraction. Because the hot cylinder is at minimum volume and the cold cylinder is at its maximum volume, the volume of the system is further reduced by compression of the cold cylinder inwards.
 * 4) The system is at its minimum volume and the gas has greater contact with the hot cylinder. The volume of the system increases by expansion of the hot cylinder.

Beta

A beta Stirling has a single power piston arranged within the same cylinder on the same shaft as a displacer piston. The displacer piston is a loose fit and does not extract any power from the expanding gas but only serves to shuttle the working gas between the hot and cold heat exchangers. When the working gas is pushed to the hot end of the cylinder it expands and pushes the power piston. When it is pushed to the cold end of the cylinder it contracts and the momentum of the machine, usually enhanced by a flywheel, pushes the power piston the other way to compress the gas. Unlike the alpha type, the beta type avoids the technical problems of hot moving seals, as the power piston is not in contact with the hot gas.

 * 1) Power piston (dark grey) has compressed the gas, the displacer piston (light grey) has moved so that most of the gas is adjacent to the hot heat exchanger.
 * 2) The heated gas increases in pressure and pushes the power piston to the farthest limit of the power stroke.
 * 3) The displacer piston now moves, shunting the gas to the cold end of the cylinder.
 * 4) The cooled gas is now compressed by the flywheel momentum. This takes less energy, since its pressure drops when it is cooled.

Other types

Other Stirling configurations continue to interest engineers and inventors.

 * The rotary Stirling engine seeks to convert power from the Stirling cycle directly into torque, similar to the rotary combustion engine. No practical engine has yet been built but a number of concepts, models and patents have been produced, such as the Quasiturbine engine.
 * A hybrid between piston and rotary configuration is a double-acting engine. This design rotates the displacers on either side of the power piston. In addition to giving great design variability in the heat transfer area, this layout eliminates all but one external seal on the output shaft and one internal seal on the piston. Also, both sides can be highly pressurized as they balance against each other.
 * Another alternative is the Fluidyne engine (or Fluidyne heat pump), which uses hydraulic pistons to implement the Stirling cycle. The work produced by a Fluidyne engine goes into pumping the liquid. In its simplest form, the engine contains a working gas, a liquid, and two non-return valves.
 * The Ringbom engine concept published in 1907 has no rotary mechanism or linkage for the displacer. This is instead driven by a small auxiliary piston, usually a thick displacer rod, with the movement limited by stops.
 * The engineer Andy Ross invented a two-cylinder Stirling engine (positioned at 0°, not 90°) connected using a special yoke.
 * The Franchot engine is a double-acting engine invented by Charles-Louis-Félix Franchot in the nineteenth century. In a double-acting engine, the pressure of the working fluid acts on both sides of the piston. One of the simplest forms of a double-acting machine, the Franchot engine consists of two pistons and two cylinders, and acts like two separate alpha machines. In the Franchot engine, each piston acts in two gas phases, which makes more efficient use of the mechanical components than a single-acting alpha machine. However, a disadvantage of this machine is that one connecting rod must have a sliding seal at the hot side of the engine, which is difficult when dealing with high pressures and temperatures.

Free-piston engines

Free-piston Stirling engines include those with liquid pistons and those with diaphragms as pistons. In a free-piston device, energy may be added or removed by an electrical linear alternator, pump or other coaxial device. This avoids the need for a linkage, and reduces the number of moving parts. In some designs, friction and wear are nearly eliminated by the use of non-contact gas bearings or very precise suspension through planar springs.

Four basic steps in the cycle of a free-piston Stirling engine are:

 * 1) The power piston is pushed outwards by the expanding gas thus doing work. Gravity plays no role in the cycle.
 * 2) The gas volume in the engine increases and therefore the pressure reduces, which causes a pressure difference across the displacer rod to force the displacer towards the hot end. When the displacer moves, the piston is almost stationary and therefore the gas volume is almost constant. This step results in the constant volume cooling process, which reduces the pressure of the gas.
 * 3) The reduced pressure now arrests the outward motion of the piston and it begins to accelerate towards the hot end again and by its own inertia, compresses the now cold gas, which is mainly in the cold space.
 * 4) As the pressure increases, a point is reached where the pressure differential across the displacer rod becomes large enough to begin to push the displacer rod (and therefore also the displacer) towards the piston and thereby collapsing the cold space and transferring the cold, compressed gas towards the hot side in an almost constant volume process. As the gas arrives in the hot side the pressure increases and begins to move the piston outwards to initiate the expansion step as explained in (1).

In the early 1960s, William T. Beale of Ohio University located in Athens, Ohio, invented a free piston version of the Stirling engine to overcome the difficulty of lubricating the crank mechanism. While the invention of the basic free piston Stirling engine is generally attributed to Beale, independent inventions of similar types of engines were made by E.H. Cooke-Yarborough and C. West at the Harwell Laboratories of the UK AERE. G.M. Benson also made important early contributions and patented many novel free-piston configurations.

The first known mention of a Stirling cycle machine using freely moving components is a British patent disclosure in 1876. This machine was envisaged as a refrigerator (i.e., the reversed Stirling cycle). The first consumer product to utilize a free piston Stirling device was a portable refrigerator manufactured by Twinbird Corporation of Japan and offered in the US by Coleman in 2004.

Flat engines

Design of the flat double-acting Stirling engine solves the drive of a displacer with the help of the fact that areas of the hot and cold pistons of the displacer are different.

The drive does so without any mechanical transmission. Using diaphragms eliminates friction and need for lubricants.

When the displacer is in motion, the generator holds the working piston in the limit position, which brings the engine working cycle close to an ideal Stirling cycle. The ratio of the area of the heat exchangers to the volume of the machine increases by the implementation of a flat design.

Flat design of the working cylinder approximates thermal process of the expansion and compression closer to the isothermal one.

The disadvantage is a large area of the thermal insulation between the hot and cold space.

Thermoacoustic cycle
Thermoacoustic devices are very different from Stirling devices, although the individual path travelled by each working gas molecule does follow a real Stirling cycle. These devices include the thermoacoustic engine and thermoacoustic refrigerator. High-amplitude acoustic standing waves cause compression and expansion analogous to a Stirling power piston, while out-of-phase acoustic travelling waves cause displacement along a temperature gradient, analogous to a Stirling displacer piston. Thus a thermoacoustic device typically does not have a displacer, as found in a beta or gamma Stirling.

Other developments
NASA has considered nuclear-decay heated Stirling Engines for extended missions to the outer solar system. In 2018, NASA and the United States Department of Energy announced that they had successfully tested a new type of nuclear reactor called KRUSTY, which stands for "Kilopower Reactor Using Stirling TechnologY", and which is designed to be able to power deep space vehicles and probes as well as exoplanetary encampments.

At the 2012 Cable-Tec Expo put on by the Society of Cable Telecommunications Engineers, Dean Kamen took the stage with Time Warner Cable Chief Technology Officer Mike LaJoie to announce a new initiative between his company Deka Research and the SCTE. Kamen refers to it as a Stirling engine.

Size and temperature
Very low-power engines have been built that run on a temperature difference of as little as 0.5 K. A displacer-type Stirling engine has one piston and one displacer. A temperature difference is required between the top and bottom of the large cylinder to run the engine. In the case of the low-temperature-difference (LTD) Stirling engine, the temperature difference between one's hand and the surrounding air can be enough to run the engine. The power piston in the displacer-type Stirling engine is tightly sealed and is controlled to move up and down as the gas inside expands. The displacer, on the other hand, is very loosely fitted so that air can move freely between the hot and cold sections of the engine as the piston moves up and down. The displacer moves up and down to cause most of the gas in the displacer cylinder to be either heated, or cooled.

Stirling engines, especially those that run on small temperature differentials, are quite large for the amount of power that they produce (i.e., they have low specific power). This is primarily due to the heat transfer coefficient of gaseous convection, which limits the heat flux that can be attained in a typical cold heat exchanger to about 500 W/(m2·K), and in a hot heat exchanger to about 500–5000 W/(m2·K). Compared with internal combustion engines, this makes it more challenging for the engine designer to transfer heat into and out of the working gas. Because of the thermal efficiency the required heat transfer grows with lower temperature difference, and the heat exchanger surface (and cost) for 1 kW output grows with (1/ΔT)2. Therefore, the specific cost of very low temperature difference engines is very high. Increasing the temperature differential and/or pressure allows Stirling engines to produce more power, assuming the heat exchangers are designed for the increased heat load, and can deliver the convected heat flux necessary.

A Stirling engine cannot start instantly; it literally needs to "warm up". This is true of all external combustion engines, but the warm up time may be longer for Stirlings than for others of this type such as steam engines. Stirling engines are best used as constant speed engines.

Power output of a Stirling tends to be constant and to adjust it can sometimes require careful design and additional mechanisms. Typically, changes in output are achieved by varying the displacement of the engine (often through use of a swashplate crankshaft arrangement), or by changing the quantity of working fluid, or by altering the piston/displacer phase angle, or in some cases simply by altering the engine load. This property is less of a drawback in hybrid electric propulsion or "base load" utility generation where constant power output is actually desirable.

Gas choice

The gas used should have a low heat capacity, so that a given amount of transferred heat leads to a large increase in pressure. Considering this issue, helium would be the best gas because of its very low heat capacity. Air is a viable working fluid, but the oxygen in a highly pressurized air engine can cause fatal accidents caused by lubricating oil explosions. Following one such accident Philips pioneered the use of other gases to avoid such risk of explosions.
 * Hydrogen's low viscosity and high thermal conductivity make it the most powerful working gas, primarily because the engine can run faster than with other gases. However, because of hydrogen absorption, and given the high diffusion rate associated with this low molecular weight gas, particularly at high temperatures, H2 leaks through the solid metal of the heater. Diffusion through carbon steel is too high to be practical, but may be acceptably low for metals such as aluminum, or even stainless steel. Certain ceramics also greatly reduce diffusion. Hermetic pressure vessel seals are necessary to maintain pressure inside the engine without replacement of lost gas. For high-temperature-differential (HTD) engines, auxiliary systems may be required to maintain high-pressure working fluid. These systems can be a gas storage bottle or a gas generator. Hydrogen can be generated by electrolysis of water, the action of steam on red hot carbon-based fuel, by gasification of hydrocarbon fuel, or by the reaction of acid on metal. Hydrogen can also cause the embrittlement of metals. Hydrogen is a flammable gas, which is a safety concern if released from the engine.
 * Most technically advanced Stirling engines, like those developed for United States government labs, use helium as the working gas, because it functions close to the efficiency and power density of hydrogen with fewer of the material containment issues. Helium is inert, and hence not flammable. Helium is relatively expensive, and must be supplied as bottled gas. One test showed hydrogen to be 5% (absolute) more efficient than helium (24% relatively) in the GPU-3 Stirling engine. The researcher Allan Organ demonstrated that a well-designed air engine is theoretically just as efficient as a helium or hydrogen engine, but helium and hydrogen engines are several times more powerful per unit volume.
 * Some engines use air or nitrogen as the working fluid. These gases have much lower power density (which increases engine costs), but they are more convenient to use and they minimize the problems of gas containment and supply (which decreases costs). The use of compressed air in contact with flammable materials or substances such as lubricating oil introduces an explosion hazard, because compressed air contains a high partial pressure of oxygen. However, oxygen can be removed from air through an oxidation reaction or bottled nitrogen can be used, which is nearly inert and very safe.
 * Other possible lighter-than-air gases include methane and ammonia.

Pressurization
In most high-power Stirling engines, both the minimum pressure and mean pressure of the working fluid are above atmospheric pressure. This initial engine pressurization can be realized by a pump, or by filling the engine from a compressed gas tank, or even just by sealing the engine when the mean temperature is lower than the mean operating temperature. All of these methods increase the mass of working fluid in the thermodynamic cycle. All of the heat exchangers must be sized appropriately to supply the necessary heat transfer rates. If the heat exchangers are well designed and can supply the heat flux needed for convective heat transfer, then the engine, in a first approximation, produces power in proportion to the mean pressure, as predicted by the West number and Beale number. In practice, the maximum pressure is also limited to the safe pressure of the pressure vessel. Like most aspects of Stirling engine design, optimization is multivariate, and often has conflicting requirements. A difficulty of pressurization is that while it improves the power, the heat required increases proportionately to the increased power. This heat transfer is made increasingly difficult with pressurization since increased pressure also demands increased thicknesses of the walls of the engine, which, in turn, increase the resistance to heat transfer.

Lubricants and friction

At high temperatures and pressures, the oxygen in air-pressurized crankcases, or in the working gas of hot air engines, can combine with the engine's lubricating oil and explode. At least one person has died in such an explosion. Lubricants can also clog heat exchangers, especially the regenerator. For these reasons, designers prefer non-lubricated, low-coefficient of friction materials (such as rulon or graphite), with low normal forces on the moving parts, especially for sliding seals. Some designs avoid sliding surfaces altogether by using diaphragms for sealed pistons. These are some of the factors that allow Stirling engines to have lower maintenance requirements and longer life than internal-combustion engines.

Efficiency
Theoretical thermal efficiency equals that of the ideal Carnot cycle, i.e. the highest efficiency attainable by any heat engine. However, though it is useful for illustrating general principles, practical Stirling engines deviate substantially from the ideal. It has been argued that its indiscriminate use in many standard books on engineering thermodynamics has done a disservice to the study of Stirling engines in general.

Stirling engines cannot achieve total efficiencies typical of an internal combustion engine, the main constraint being thermal efficiency. During internal combustion, temperatures achieve around 1500 °C–1600 °C for a short period of time, resulting in greater mean heat supply temperature of the thermodynamic cycle than any Stirling engine could achieve. It is not possible to supply heat at temperatures that high by conduction, as it is done in Stirling engines because no material could conduct heat from combustion in that high temperature without huge heat losses and problems related to heat deformation of materials.

Stirling engines are capable of quiet operation and can use almost any heat source. The heat energy source is generated external to the Stirling engine rather than by internal combustion as with the Otto cycle or Diesel cycle engines. This type of engine is currently generating interest as the core component of micro combined heat and power (CHP) units, in which it is more efficient and safer than a comparable steam engine. However, it has a low power-to-weight ratio, rendering it more suitable for use in static installations where space and weight are not at a premium.

Other real-world issues reduce the efficiency of actual engines, due to the limits of convective heat transfer and viscous flow (friction). There are also practical, mechanical considerations: for instance, a simple kinematic linkage may be favoured over a more complex mechanism needed to replicate the idealized cycle, and limitations imposed by available materials such as non-ideal properties of the working gas, thermal conductivity, tensile strength, creep, rupture strength, and melting point. A question that often arises is whether the ideal cycle with isothermal expansion and compression is in fact the correct ideal cycle to apply to the Stirling engine. Professor C. J. Rallis has pointed out that it is very difficult to imagine any condition where the expansion and compression spaces may approach isothermal behavior and it is far more realistic to imagine these spaces as adiabatic. An ideal analysis where the expansion and compression spaces are taken to be adiabatic with isothermal heat exchangers and perfect regeneration was analyzed by Rallis and presented as a better ideal yardstick for Stirling machinery. He called this cycle the 'pseudo-Stirling cycle' or 'ideal adiabatic Stirling cycle'. An important consequence of this ideal cycle is that it does not predict Carnot efficiency. A further conclusion of this ideal cycle is that maximum efficiencies are found at lower compression ratios, a characteristic observed in real machines. In an independent work, T. Finkelstein also assumed adiabatic expansion and compression spaces in his analysis of Stirling machinery

The ideal Stirling cycle is unattainable in the real world, as with any heat engine. The efficiency of Stirling machines is also linked to the environmental temperature: higher efficiency is obtained when the weather is cooler, thus making this type of engine less attractive in places with warmer climates. As with other external combustion engines, Stirling engines can use heat sources other than the combustion of fuels. For example, various designs for solar-powered Stirling engines have been developed.

Comparison with internal combustion engines
In contrast to internal combustion engines, Stirling engines have the potential to use renewable heat sources more easily, and to be quieter and more reliable with lower maintenance. They are preferred for applications that value these unique advantages, particularly if the cost per unit energy generated is more important than the capital cost per unit power. On this basis, Stirling engines are cost-competitive up to about 100 kW.

Compared to an internal combustion engine of the same power rating, Stirling engines currently have a higher capital cost and are usually larger and heavier. However, they are more efficient than most internal combustion engines. Their lower maintenance requirements make the overall energy cost comparable. The thermal efficiency is also comparable (for small engines), ranging from 15% to 30%. For applications such as micro-CHP, a Stirling engine is often preferable to an internal combustion engine. Other applications include water pumping, astronautics, and electrical generation from plentiful energy sources that are incompatible with the internal combustion engine, such as solar energy, and biomass such as agricultural waste and other waste such as domestic refuse. However, Stirling engines are generally not price-competitive as an automobile engine, because of high cost per unit power, & low power density.

Basic analysis is based on the closed-form Schmidt analysis.

Advantages of Stirling engines compared to internal combustion engines include:

 * Stirling engines can run directly on any available heat source, not just one produced by combustion, so they can run on heat from solar, geothermal, biological, nuclear sources or waste heat from industrial processes.
 * A continuous combustion process can be used to supply heat, so those emissions associated with the intermittent combustion processes of a reciprocating internal combustion engine can be reduced.
 * Some types of Stirling engines have the bearings and seals on the cool side of the engine, where they require less lubricant and last longer than equivalents on other reciprocating engine types.
 * The engine mechanisms are in some ways simpler than other reciprocating engine types. No valves are needed, and the burner system can be relatively simple. Crude Stirling engines can be made using common household materials.
 * A Stirling engine uses a single-phase working fluid that maintains an internal pressure close to the design pressure, and thus for a properly designed system the risk of explosion is low. In comparison, a steam engine uses a two-phase gas/liquid working fluid, so a faulty overpressure relief valve can cause an explosion.
 * In some cases, low operating pressure allows the use of lightweight cylinders.
 * They can be built to run quietly and without an air supply, for air-independent propulsion use in submarines.
 * They start easily (albeit slowly, after warmup) and run more efficiently in cold weather, in contrast to the internal combustion, which starts quickly in warm weather, but not in cold weather.
 * A Stirling engine used for pumping water can be configured so that the water cools the compression space. This increases efficiency when pumping cold water.
 * They are extremely flexible. They can be used as CHP (combined heat and power) in the winter and as coolers in summer.
 * Waste heat is easily harvested (compared to waste heat from an internal combustion engine), making Stirling engines useful for dual-output heat and power systems.
 * In 1986 NASA built a Stirling automotive engine and installed it in a Chevrolet Celebrity. Fuel economy was improved 45% and emissions were greatly reduced. Acceleration (power response) was equivalent to the standard internal combustion engine. This engine, designated the Mod II, also nullifies arguments that Stirling engines are heavy, expensive, unreliable, and demonstrate poor performance. A catalytic converter, muffler and frequent oil changes are not required.

Disadvantages of Stirling engines compared to internal combustion engines include:

 * Stirling engine designs require heat exchangers for heat input and for heat output, and these must contain the pressure of the working fluid, where the pressure is proportional to the engine power output. In addition, the expansion-side heat exchanger is often at very high temperature, so the materials must resist the corrosive effects of the heat source, and have low creep. Typically these material requirements substantially increase the cost of the engine. The materials and assembly costs for a high-temperature heat exchanger typically accounts for 40% of the total engine cost.
 * All thermodynamic cycles require large temperature differentials for efficient operation. In an external combustion engine, the heater temperature always equals or exceeds the expansion temperature. This means that the metallurgical requirements for the heater material are very demanding. This is similar to a Gas turbine, but is in contrast to an Otto engine or Diesel engine, where the expansion temperature can far exceed the metallurgical limit of the engine materials, because the input heat source is not conducted through the engine, so engine materials operate closer to the average temperature of the working gas.
 * The Stirling cycle is not actually achievable; the real cycle in Stirling machines is less efficient than the theoretical Stirling cycle. The efficiency of the Stirling cycle is lower where the ambient temperatures are mild, while it would give its best results in a cool environment, such as northern countries' winters.
 * Dissipation of waste heat is especially complicated because the coolant temperature is kept as low as possible to maximize thermal efficiency. This increases the size of the radiators, which can make packaging difficult. Along with materials cost, this has been one of the factors limiting the adoption of Stirling engines as automotive prime movers. For other applications such as ship propulsion and stationary microgeneration systems using combined heat and power (CHP) high power density is not required.

Applications

Applications of the Stirling engine range from heating and cooling to underwater power systems. A Stirling engine can function in reverse as a heat pump for heating or cooling. Other uses include combined heat and power, solar power generation, Stirling cryocoolers, heat pump, marine engines, low power model aircraft engines, and low temperature difference engines.

General and cited references

 * E.H. Cooke-Yarborough (1970). "Heat Engines", US patent 3548589. Granted to Atomic Energy Authority UK, 22 December 1970.
 * E.H. Cooke-Yarborough (1967). "A Proposal for a Heat-Powered Nonrotating Electrical Alternator", Harwell Memorandum AERE-M881.
 * E.H. Cooke-Yarborough (1967). "A Proposal for a Heat-Powered Nonrotating Electrical Alternator", Harwell Memorandum AERE-M881.

title: Stirling engine