A steam engine is a heat engine A heat engine is a physical device that converts thermal energy to mechanical output. The mechanical output is called work, and the thermal energy input is called heat. Heat engines typically run on a specific thermodynamic cycle. Heat engines can be open to the atmospheric air or sealed and closed off to the outside that performs mechanical work In physics, mechanical work is the amount of energy transferred by a force acting through a distance. Like energy, it is a scalar quantity, with SI units of joules. The term work was first coined in 1826 by the French mathematician Gaspard-Gustave Coriolis using steam Steam is either mist , or the gas phase of water (water vapor) as its working fluid The working fluid in a machine is the pressurized gas or liquid which actuates the machine. Examples include steam in a steam engine, air in a hot air engine and hydraulic fluid in a hydraulic motor or hydraulic cylinder. More generally, a thermodynamic system consists of a system boundary across which energy transfers occur. The working fluid is.
The idea of using boiling water to produce mechanical motion has a long history, going back about 2,000 years. Early devices were not practical power producers, but more advanced designs producing usable power have become a major source of mechanical power over the last 300 years, enabling the Industrial Revolution The Industrial Revolution was a period from the 18th to the 19th century where major changes in agriculture, manufacturing, mining, transport and technology had a profound effect on the socioeconomic and cultural conditions starting in the United Kingdom, then subsequently spreading throughout Europe, North America, and eventually the world. The, beginning with applications for mine water removal using vacuum engines. Subsequent developments using pressurized steam and converting to rotational motion enabled the powering of a wide range of manufacturing machinery anywhere water and coal Coal is a readily combustible black or brownish-black sedimentary rock normally occurring in rock strata in layers or veins called coal beds. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure. Coal is composed primarily of carbon along with variable or wood fuel Wood fuel is wood used as fuel. The burning of wood is currently the largest use of energy derived from a solid fuel biomass. Wood fuel can be used for cooking and heating, and occasionally for fueling steam engines and steam turbines that generate electricity. Wood fuel may be available as firewood , charcoal, chips, sheets, pellets and sawdust could be obtained, previously restricted only to locations where water wheels A water wheel is a machine for converting the energy of free-flowing or falling water into useful forms of power. the development of hydropower. In the Middle Ages, waterwheels were used as tools to power factories throughout different countries. The alternatives were the windmill and human and animal power. The most common use of the water wheel or windmills A windmill is a machine which converts the energy of wind to rotational motion by means of adjustable vanes called sails. The main use is for a grinding mill powered by the wind, reducing a solid or coarse substance into pulp or minute grains, by crushing, grinding, or pressing. Windmills have also provided energy to sawmills, paper mills, could be used. Significantly, this power source would later be applied to prime movers, mobile devices such as steam tractors In North America, the term steam tractor usually refers to a type of agricultural tractor powered by a steam engine, used extensively in the late 19th and early 20th centuries and railway locomotives A steam locomotive is a locomotive powered by a steam engine. The term usually refers to its use on railways, but can also refer to a "road locomotive" such as a traction engine or steamroller. Modern steam turbines A steam turbine is a mechanical device that extracts thermal energy from pressurized steam, and converts it into rotary motion. Its modern manifestation was invented by Sir Charles Parsons in 1884 generate about 80 percent of the electric power Electric power is defined as the rate at which electrical energy is transferred by an electric circuit. The SI unit of power is the watt in the world using a variety of heat sources[citation needed].
Steam engines are typically external combustion engines An external combustion engine is a heat engine where an (internal) working fluid is heated by combustion of an external source, through the engine wall or a heat exchanger. The fluid then, by expanding and acting on the mechanism of the engine produces motion and usable work. The fluid is then cooled, compressed and reused (closed cycle), or (less,[1] E.C.E.[›] although other external sources of heat such as solar power Solar power is the generation of electricity from sunlight. This can be direct as with photovoltaics , or indirect as with concentrating solar power (CSP), where the sun's energy is focused to boil water which is then used to provide power. Solar power provided 0.02% of the total world energy consumption in 2008. The largest solar power plants,, nuclear power Nuclear power is produced by controlled nuclear reactions. Commercial and utility plants currently use nuclear fission reactions to heat water to produce steam, which is then used to generate electricity or geothermal The geothermal gradient is the rate at which the Earth's temperature increases with depth, indicating heat flowing from the Earth's warm interior to its cooler surface. Away from tectonic plate boundaries, it is 25-30°C per km of depth in most of the world. Strictly speaking, geo-thermal necessarily refers to the Earth but the concept may be energy may be used. The heat cycle is known as the Rankine cycle The Rankine cycle is a thermodynamic cycle which converts heat into work. The heat is supplied externally to a closed loop, which usually uses water as the working fluid. This cycle generates about 80% of all electric power used throughout the world, including virtually all solar thermal, biomass, coal and nuclear power plants. It is named after.
In general usage, the term 'steam engine' can refer to integrated steam plants such as railway steam locomotives A steam locomotive is a locomotive powered by a steam engine. The term usually refers to its use on railways, but can also refer to a "road locomotive" such as a traction engine or steamroller and portable engines A portable engine is a small steam engine, mounted on wheels or skids, which is used for driving machinery using a belt from its flywheel. It is not self-propelled and is towed to the work site by horses or bullocks, or even a traction engine. Portable engines were used mainly for driving agricultural machinery, such as threshing machines. In, or may refer to the machinery alone, as in the beam engine The first beam engines were water-powered, and used to pump water from mines. A 'preserved' example may be seen at Wanlockhead, in Scotland and stationary steam engine Stationary steam engines are fixed steam engines used for pumping or driving mills and factories, and for power generation. They are distinct from locomotive engines used on railways, traction engines for heavy steam haulage on roads, steam cars , agricultural engines used for ploughing or threshing, and marine engines. Specialized devices such as steam hammers A steam hammer is a power-driven hammer used to shape forgings. It consists of a hammer-like piston located within a cylinder. The hammer is raised by the pressure of steam injected into the lower part of a cylinder and falls down with a force by removing the steam. Usually, the hammer is made to fall faster by injecting steam into the upper part and steam pile drivers A pile driver is a mechanical device used to drive piles into soil to provide foundation support for buildings or other structures. The term is also used in reference to members of the construction crew that work with pile-driving rigs are dependent on steam supplied from a separate boiler A boiler or steam generator is a device used to create steam by applying heat energy to water. Although the definitions are somewhat flexible, it can be said that older steam generators were commonly termed boilers and worked at low to medium pressure , but at pressures above that figure it is more usual to speak of a steam generator.
Applications
Since the early 18th century steam power has been applied to a variety of practical uses. At first it was applied to reciprocating pumps, but from the 1780s rotative engines (i.e. those converting reciprocating motion Reciprocating motion , also called reciprocation, is an up-and-down motion which repeats over and over again. It is found in a wide range of mechanisms such as reciprocating engines and pumps. The two opposite motions that comprise a single reciprocation cycle are called strokes into rotary motion) began to appear, driving factory machinery. At the turn of the 19th century, steam-powered transport on both sea and land began to make its appearance becoming ever more dominant as the century progressed.
Steam engines can be said to have been the moving force behind the Industrial Revolution The Industrial Revolution was a period from the 18th to the 19th century where major changes in agriculture, manufacturing, mining, transport and technology had a profound effect on the socioeconomic and cultural conditions starting in the United Kingdom, then subsequently spreading throughout Europe, North America, and eventually the world. The and saw widespread commercial use driving machinery in factories and mills, powering pumping stations Pumping stations are facilities including pumps and equipment for pumping fluids from one place to another. They are used for a variety of infrastructure systems, such as the supply of water to canals, the drainage of low-lying land, and the removal of sewage to processing sites and transport appliances such as railway locomotives, ships and road vehicles. Their use in agriculture led to an increase in the land available for cultivation.
Very low power engines are used to power models and speciality applications such as the steam clock A steam clock is a clock which is fully or partially powered by a steam engine. Only a few functioning steam clocks exist, most designed and built by Canadian horologist Raymond Saunders for display in urban public spaces. Steam clocks built by Saunders are located in Otaru, Japan; Indianapolis, USA; and the Canadian cities of Vancouver, Whistler.
The presence of several phases between heat source and power delivery has meant that it has always been difficult to obtain a power-to-weight ratio anywhere near that obtainable from internal combustion engines The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer (usually air) in a combustion chamber. In an internal combustion engine the expansion of the high temperature and pressure gases, which are produced by the combustion, directly applies force to a movable component of the engine, such as the; notably this has made steam aircraft Steam aircraft are aircraft that are propelled by steam engines. They were unusual devices because of the difficulty in producing a powerplant with a high enough power to weight ratio to be practical. They are distinct from airships that use steam as their lifting gas which are known as thermal airships extremely rare. Similar considerations have meant that for small and medium-scale applications steam has been largely superseded by internal combustion engines or electric motors An electric motor uses electrical energy to produce mechanical energy, very typically through the interaction of magnetic fields and current-carrying conductors. The reverse process, producing electrical energy from mechanical energy, is accomplished by a generator or dynamo. Many types of electric motors can be run as generators, and vice versa, which has given the steam engine an out-dated image. However it is important to remember that the power supplied to the electric grid When referring to the power industry, "grid" is a term used for an electricity network which may support all or some of the following three distinct operations: is predominantly generated using steam turbine A turbine is a rotary engine that extracts energy from a fluid flow and converts it into useful work plant, so that indirectly the world's industry is still dependent on steam power. Recent concerns about fuel sources and pollution have incited a renewed interest in steam both as a component of cogeneration Cogeneration is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat. It is one of the most common forms of energy recycling processes and as a prime mover. This is becoming known as the Advanced Steam movement.
Steam engines can be classified by their application:
Stationary applications
Stationary steam engines Stationary steam engines are fixed steam engines used for pumping or driving mills and factories, and for power generation. They are distinct from locomotive engines used on railways, traction engines for heavy steam haulage on roads, steam cars , agricultural engines used for ploughing or threshing, and marine engines can be classified into two main types:
- Winding engines, rolling mill In metalworking, rolling is a metal forming process in which metal stock is passed through a pair of rolls. Rolling is classified according to the temperature of the metal rolled. If the temperature of the metal is above its recrystallization temperature, then the process is termed as hot rolling. If the temperature of the metal is below its engines, steam donkeys, marine engines, and similar applications which need to frequently stop and reverse.
- Engines providing power, which rarely stop and do not need to reverse. These include engines used in thermal power stations and those that were used in pumping stations Pumping stations are facilities including pumps and equipment for pumping fluids from one place to another. They are used for a variety of infrastructure systems, such as the supply of water to canals, the drainage of low-lying land, and the removal of sewage to processing sites, mills A grinding mill is a unit operation designed to break a solid material into smaller pieces. There are many different types of grinding mills and many types of materials processed in them. Historically mills were powered by hand , working animal, wind (windmill) or water (watermill). Today they are also powered by electricity, factories A factory or manufacturing plant is an industrial building where laborers manufacture goods or supervise machines processing one product into another. Most modern factories have large warehouses or warehouse-like facilities that contain heavy equipment used for assembly line production. Typically, factories gather and concentrate resources: and to power cable railways A cable railway is a steeply graded railway that uses a cable or rope to haul trains and cable tramways before the widespread use of electric power Electric power is defined as the rate at which electrical energy is transferred by an electric circuit. The SI unit of power is the watt.
The steam donkey is technically a stationary engine A stationary engine is an engine whose framework does not move. It is normally used not to propel a vehicle but to drive a piece of immobile equipment such as a pump or power tool. They may be powered by steam; or oil-burning or internal combustion engines. They come in a wide variety of sizes and are used a wide variety of purposes. These include: but is mounted on skids to be semi-portable. It is designed for logging Logging is the process in which certain trees are cut down by a lumberjack or machine, such as the feller buncher, for forest management and timber use and can drag itself to a new location. Having secured the winch cable to a sturdy tree at the desired destination, the machine will move towards the anchor point as the cable is winched in.
A portable engine A portable engine is a small steam engine, mounted on wheels or skids, which is used for driving machinery using a belt from its flywheel. It is not self-propelled and is towed to the work site by horses or bullocks, or even a traction engine. Portable engines were used mainly for driving agricultural machinery, such as threshing machines. In is a stationary engine mounted on wheels so that it may be towed to a work-site by horses or a traction engine A traction engine is a self-propelled steam engine used to move heavy loads on roads, plough ground or to provide power at a chosen location. The name derives from the Latin tractus, meaning 'drawn', since the prime function of any traction engine is to draw a load behind it. They are sometimes called road locomotives to distinguish them from, rather than being fixed in a single location.
Transport applications
A steam locomotive- a GNR N2 Class No.1744 at Weybourne nr. Sheringham, Norfolk.Steam engines have been used to power a wide array of transport appliances:
- Marine: Steamboat A steamboat or steamship, sometimes called a steamer, is a ship in which the primary method of propulsion is steam power, typically driving propellers or paddlewheels, steamship A steamboat or steamship, sometimes called a steamer, is a ship in which the primary method of propulsion is steam power, typically driving propellers or paddlewheels, steam yacht
- Rail: Steam locomotive A steam locomotive is a locomotive powered by a steam engine. The term usually refers to its use on railways, but can also refer to a "road locomotive" such as a traction engine or steamroller, fireless locomotive
- Agriculture: Traction engine A traction engine is a self-propelled steam engine used to move heavy loads on roads, plough ground or to provide power at a chosen location. The name derives from the Latin tractus, meaning 'drawn', since the prime function of any traction engine is to draw a load behind it. They are sometimes called road locomotives to distinguish them from, steam tractor
- Road: Steam wagon, steam bus, steam tricycle, steam car
- Construction: Steam roller, steam shovel
- Military: steam tank (tracked), steam tank (wheeled), steam catapult
- Space: Steam rocket
In these applications internal combustion engines are now used due to their higher power-to-weight ratio , lower maintenance and space requirements .
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Sarina del Fuego
ue, 20 Jul 2010 06:13:45 GM
This is an awesome performance night for all you alternate souls out and about. Its going to have Magic, Fashion Shows, Piercing and Burlesque just to gi...
