The major components of a Watt pumping engine.

The Watt steam engine was the first type of steam engine to make use of steam at a pressure above atmospheric. Improving on the design of the 1711 Newcomen engine, the Watt steam engine, developed sporadically from 1763 to 1775, was the next great step in the development of the steam engine. Offering a dramatic increase in fuel efficiency, the new design soon replaced Newcomen engines in areas where coal was expensive, and then went on to be used in the place of most natural power sources such as wind and water. James Watt's design became synonymous with steam engines, due in no small part to his business partner, Matthew Boulton. Image File history File links Size of this preview: 631 × 600 pixel Image in higher resolution (2367 × 2250 pixel, file size: 591 KB, MIME type: image/jpeg) Thurston Robert H: History of the Growth of the Steam engine, D. Appleton & Co 1878 This image is in the public domain in... Image File history File links Size of this preview: 631 × 600 pixel Image in higher resolution (2367 × 2250 pixel, file size: 591 KB, MIME type: image/jpeg) Thurston Robert H: History of the Growth of the Steam engine, D. Appleton & Co 1878 This image is in the public domain in... // The term steam engine may also refer to an entire railroad steam locomotive. ... Diurnal (daily) rhythm of air pressure in northern Germany (black curve is air pressure) Atmospheric pressure is the pressure at any point in the Earths atmosphere. ... Animation of a schematic Newcomen steam engine. ... 1763 was a common year starting on Saturday (see link for calendar). ... Year 1775 (MDCCLXXV) was a common year starting on Sunday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Thursday of the 11-day slower Julian calendar). ... Fuel efficiency sometimes means the same as thermal efficiency, that is, the efficiency of converting energy contained in a carrier fuel to kinetic energy or work. ... For other persons named James Watt, see James Watt (disambiguation). ... Matthew Boulton. ...

Introduction

In 1698, the English mechanical designer Thomas Savery invented a steam pumping appliance that drew water directly from a well by a vacuum, then sent it up to a higher level by steam pressure. The appliance was also proposed for draining mines, but limited pumping height made this impracticable. It also consumed an inordinate amount of fuel. For other uses, see England (disambiguation). ... Thomas Savery (c. ... Chuquicamata, the second largest open pit copper mine in the world, Chile. ...

The solution to draining deep mines was found by Thomas Newcomen who developed an "atmospheric" engine working only on the vacuum principle. It employed a cylinder containing a moveable piston connected by a chain to one end of a rocking beam that worked a mechanical lift pump from its opposite end. The top side of the power cylinder was open to the atmosphere, steam being introduced at top stroke to the underside of the piston then water sprayed in, condensing the steam and creating a vacuum; thus atmospheric pressure acting on the upper side of the piston drove it down. Chuquicamata, the second largest open pit copper mine in the world, Chile. ... Thomas Newcomen (baptised 24 February 1664; died 5 August 1729) was an ironmonger by trade, and a Baptist lay preacher by calling. ...

A Watt steam engine, the steam engine that propelled the Industrial Revolution in Britain and the world, located in the lobby of the Superior Technical School of Industrial Engineers of the UPM (Madrid).

It was both powerful and useful and for the first time water could be raised from a depth of over 150 feet. The first example from 1711 was able to replace 500 horses. In the next fifty years only a few small changes were made to the basic engine, seventy-five examples of which were at mines in Britain, France, Holland, Sweden and Russia. Wikipedia does not have an article with this exact name. ... Wikipedia does not have an article with this exact name. ... // The term steam engine may also refer to an entire railroad steam locomotive. ... This article is about the Spanish capital. ... 1711 (MDCCXI) was a common year starting on Thursday of the Gregorian calendar (or a common year starting on Monday of the 11-day slower Julian calendar). ... Binomial name Equus caballus Linnaeus, 1758 The horse (Equus caballus, sometimes seen as a subspecies of the Wild Horse, Equus ferus caballus) is a large odd-toed ungulate mammal, one of ten modern species of the genus Equus. ...

The system brought great practical benefits, but at the price of very high coal consumption as the water jet into the cylinder cooled the walls at each stroke; this meant that when the next charge of steam was introduced it would continue condensing until the cylinder approached working temperature.

Separate condenser

A Scottish instrument maker, James Watt, was given the job in 1763 of repairing a model Newcomen engine for the University of Glasgow, and noted how inefficient it was. In 1765, while wandering across Glasgow Green he conceived the idea of a separate condensing chamber for the steam engine. Watt's idea was to separate the condensation system from the cylinder, injecting the cooling water spray in a second cylinder, connected to the main one. When the piston had reached the top of the cylinder, the inlet valve was closed and the valve controlling the passage to the condenser was opened. External atmospheric pressure would then push the piston towards the condenser. Thus the condenser could be kept cold and under less than atmospheric pressure, while the cylinder remained hot. This article is about the country. ... For other persons named James Watt, see James Watt (disambiguation). ... 1763 was a common year starting on Saturday (see link for calendar). ... Master of Theology (MTh) Dentistry Nursing Affiliations Russell Group Universitas 21 Website http://www. ... Year 1765 (MDCCLXV) was a common year starting on Tuesday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Saturday of the 11-day slower Julian calendar). ... McLennan Arch at the north-west entrance to Glasgow Green Glasgow Green situated in the east end of the city on the north bank of the River Clyde, is the oldest park in Glasgow dating back to the 15th century. ... Look up condenser in Wiktionary, the free dictionary. ... For the use of the term in optics, see piston (optics). ... Cylinder with piston in a steam engine A cylinder in the central working part of a reciprocating engine, the space in which a piston travels. ... Diurnal (daily) rhythm of air pressure in northern Germany (black curve is air pressure) Atmospheric pressure is the pressure at any point in the Earths atmosphere. ...

Watt also realised that the new operating cycle might increase engine speed and the power produced. Suppose low pressure steam could now be substituted for atmospheric pressure? If the top of the cylinder was closed off, the steam could act upon the piston during the power stroke; the low steam pressure would not be sufficient to move it in normal circumstances, but it could if acting upon a vacuum.

This led to the fully developed version of 1775 that actually went into production ^[1]. There was no spray, the condenser being immersed in a water tank and at each stroke the warm condensate was drawn off and sent up to a hot well by a vacuum pump which also helped to evacuate the steam from under the power cylinder. The still-warm condensate was recycled as feedwater for the boiler.

Matthew Boulton

The separate condenser showed dramatic potential for improvements on the Newcomen engine but Watt was still discouraged by seemingly insurmountable problems before a marketable engine could be perfected. It was only after entering into partnership with Matthew Boulton that such became reality. Watt told Boulton about his ideas on improving the engine, and Boulton, an avid entrepreneur, agreed to fund development of a test engine at Soho, near Birmingham. At last Watt had access to facilities and the practical experience of craftsmen who were soon able to get the first engine working. As fully developed, it used about 75% less fuel than a similar Newcomen one. In order to be able to recoup substantial development costs, Boulton and Watt licensed the idea to existing Newcomen engine owners, taking a share of the cost of fuel they saved. Matthew Boulton. ... An entrepreneur (a loanword from French introduced and first defined by the Irish economist Richard Cantillon) is a person who operates a new enterprise or venture and assumes some accountability for the inherent risks. ... This article is about the area of Birmingham. ... This article is about the British city. ... The firm of Boulton and Watt, a partnership between Matthew Boulton and James Watt, made steam engines at their Soho Foundry in Smethwick, near Birmingham, England. ...

Later improvements

Driving the engines by the pressure differential between low-pressure steam and a partial vacuum raised the possibility of reciprocating engine development^[2]. An arrangement of valves could admit steam to either end, or connect either end with the condenser. Consequently, the direction of the power stroke might be reversed. The resulting double action gave a very even movement to the beam and made possible the development of rotative engines. Furthermore, the linkage to the beam had, until then, been by means of a chain, which meant that power could only be applied in one direction, by pulling; it had to be made possible for the piston to also push the beam whilst keeping the piston rod vertical; this Watt achieved by developing his parallel motion. Components of a typical, four stroke cycle, DOHC piston engine. ... // The term steam engine may also refer to an entire railroad steam locomotive. ... The parallel motion was a mechanical linkage invented by James Watt in 1784 for his double-acting steam engine. ...

In order to avoid patent rights already claimed by another party, on the use of the crank, he adopted the epicyclic sun and planet gear system suggested by an employee William Murdoch, only later reverting once the patent rights had expired to the more familiar crank seen on most engines today. Epicyclic gearing is used here to increase output speed. ... The sun and planet gear was a method of converting vertical motion to rotary motion and utilised a reciprocating steam engine. ... William Murdoch. ... Crankshaft (red), pistons (gray) in their cylinders (blue), and flywheel (black) Continental engine marine crankshafts, 1942 Components of a typical, four stroke cycle, DOHC piston engine. ...

Because factory machinery needed to operate at a constant speed, Watt adapted the centrifugal governor (earlier used to automatically control the speed of windmills) linked to a steam regulator valve. A centrifugal governor is a specific type of governor that controls the speed of an engine by regulating the amount of fuel admitted, so as to maintain a near constant speed whatever the load or fuel supply conditions. ...

These improvements allowed the steam engine to be used to replace water wheels, thereby freeing British industry from geographical constraints and becoming one of the main drivers in the industrial revolution. An overshot water wheel standing 42 feet high powers the Old Mill at Berry College in Rome, Georgia A water wheel (also waterwheel, Norse mill, Persian wheel or noria) is a hydropower system; a system for extracting power from a flow of water. ... A Watt steam engine, the steam engine that propelled the Industrial Revolution in Britain and the world. ...

Watt was also concerned with fundamental research on the functioning of the steam engine. His most notable measuring device, still in use today is the Watt indicator incorporating a manometer to measure steam pressure within the cylinder according to the position of the piston; this enabled a diagram to be produced representing the action of the steam throughout the cycle. A manometer is a pressure measuring instrument, often also called pressure gauge. ... In the technology of the steam engine, the indicator diagram was a device developed by James Watt and his employee John Southern to improve the efficiency of engines. ...

Preserved Watt engines

The oldest working engine in the world is the Smethwick Engine, brought into service in May 1779 and now at Thinktank in Birmingham (formerly at the now defunct Museum of Science and Industry, Birmingham). The oldest still in its original engine house and still capable of doing the job for which it was installed is the 1812 Boulton and Watt engine at the Crofton Pumping Station. This was used to pump water for the Kennet and Avon Canal; on certain weekends throughout the year the modern pumps are switched off and the two steam engines at Crofton still perform this function. The oldest rotative steam engine (the third rotative engine ever built) is located in the Powerhouse Museum in Sydney, Australia. The Smethwick Engine is a steam engine made by Boulton and Watt, brought into service in May 1779. ... 1779 was a common year starting on Friday (see link for calendar). ... Thinktank is a science museum in Birmingham, England. ... This article is about the British city. ... Vacant Science Museum, formerly Elkington Silver Electroplating Works The now defunct Birmingham Science Museum, or Museum of Science and Industry, previously the Elkington Silver Electroplating Works, is a building on Newhall Street in Birmingham, England. ... The pumping station viewed from the canal; showing tunnel under railway, boilerhouse, enginehouse and chimney Wilton Water, the canal and railway from the pumping station The boilerhouse The beam gallery with the 1812 engine in operation Crofton Pumping Station is a pumping station, located near the village of Great Bedwyn... The canal at Bathampton, near Bath The Kennet and Avon Canal is a canal in southern England. ... Powerhouse entry The Powerhouse Museum is Sydneys museum of science and technology. ...

See also

• Carnot cycle
• Heat engine
• Thermodynamics
• James Watt
• Newcomen steam engine

The Carnot cycle is a particular thermodynamic cycle, modeled on the Carnot heat engine, studied by Nicolas Léonard Sadi Carnot in the 1820s and expanded upon by Benoit Paul Émile Clapeyron in the 1830s and 40s. ... A heat engine is a physical or theoretical device that converts thermal energy to mechanical output. ... Thermodynamics (from the Greek θερμη, therme, meaning heat and δυναμις, dynamis, meaning power) is a branch of physics that studies the effects of changes in temperature, pressure, and volume on physical systems at the macroscopic scale by analyzing the collective motion of their particles using statistics. ... For other persons named James Watt, see James Watt (disambiguation). ... Animation of a schematic Newcomen steam engine. ...

References

1. ^ Hulse David K (1999): "The early development of the steam engine"; TEE Publishing, Leamington Spa, U.K., ISBN, 85761 107 1 p. 127 et seq.
2. ^ Hulse David K (2001): "The development of rotary motion by the steam power"; TEE Publishing, Leamington Spa, U.K., ISBN, 1 85761 119 5 : p 58 et seq.

External links

• Watt atmospheric engine - Michigan State University, Chemical Engineering
• Watt's 'perfect engine' - excerpts from Transactions of the Newcomen Society.
• Boulton and Watt Steam Engine at the Powerhouse Museum, Sydney